Karter16

Karter 16's E46 M3 Journal

47 posts in this topic

Hey guys,

I've recently started a build journal on a US site (m3forum.net). I thought I might as well replicate it here as well. Some of the content is written for a US audience (miles vs km, LHD vs RHD, etc) so feel free to ignore those bits. I'll update here as I update on m3forum.

 

So having owned my M3 for a year last week, and given I'm embarking on some significant work over the next month, I though it was about time I started a build thread.

I got the car in December 2015. I first seriously looked at buying an M3 in 2008, I decided (wisely) to pay off my student loan, etc. first. I then ended up getting married in 2012, and spending some time & money on travel with my wife. In 2015 I was finally ready to start thinking about an M3 again. 

For a number of weeks in August and September I had my eye half-seriously on a 2005 Silver Grey SMG model for sale in my home city (living in New Zealand there's not a huge number of E46 M3's on sale (between 5 and 8 at any one time). I still wasn't really sure if I was ready to buy one or not. Then one day it was sold, and I realised then how much I actually wanted it... I thought that was it and prepared myself to wait until the next one that met my requirements came along. Then, a few weeks later the same car was back on the market. It had actually just been traded between dealers. In the mean time the second dealer had done some work on it (to make it more attractive for sale presumably).

  • New wing mirror glass on both sides to replace the damaged ones on it.
  • All trim parts on the centre console replaced - looked like new.
  • New OE brake rotors fitted on the front.

That weekend I went to have a look at it. It was in much better shape that I was expecting. The exterior wasn't perfect, which I was expecting from what others who had looked at it had said. But the interior was in really great condition. More importantly the mechanics of the car seemed to be solid. The car had had the subframe strengthened by BMW NZ, had been serviced at a reputable BMW dealer, and had had things like the RTAB's done a few years previously, which was an indication that the previous owner/s had been taking at least some care of the car.

To make a short story even shorter, I ended up making an offer on the car, and I took it home 3 days before Christmas. 

IMG_0563%201_zps07zrojg5.jpg


It ticked pretty much all the boxes for me. I was looking for:

  • A later manufacturing year (2005/2006).
  • SMG (yep I know, but I'm an engineer, SMG is cool, its a differentiator, and I really wanted it).
  • Silvergrey or LSB
  • Sunroof
  • 19in Style 67s

 

I bought it knowing that quite possibly it would need the VANOS done (which indeed it did), but that didn't really bother me. My intent in buying this car was to work on it, maintain it, and make it better than the day I bought it. I plan on keeping this car for a long time, and its an opportunity to learn and develop my mechanics skills as I go. I'm lucky in that regard in that I have my dad to help me. When he was about my age he owned and restored a Daimler SP250, so I'm not exactly on my own on this.

A couple of months after I bought the car I ordered the parts to do the Beisan VANOS rebuild, did the full rebuild, new exhaust disc (existing hub tabs are 100% good), timing chain tensioner, cam bolts, etc. It was a great first project, we spread the work over two days, took our time, and the end result was perfect. All the rattle was gone, and the engine sounded smooth. :EWBTE-min:

Over the New Zealand winter I didn't get any major work done. did new belts, pulleys and tensioners, and replaced the crank case ventilation separator, but not much else.

Which leads into the present day :)

The summer project is a full suspension & bushings rebuild, cleaning up the underside of the car, cleaning, painting, etc. The aim is that the underside of the car will be as close to "like new" as is realistically possible. For me that means:

  • Replace parts that wear
  • Clean everything else up
  • Seal and paint where appropriate to protect

In New Zealand we don't salt our roads in winter (mostly cause it doesn't get cold enough) so the car is in pretty reasonable condition (more dirt and grime than rush), but if you're under there you might as well do it right hey!

A couple of weeks ago I ordered Koni yellows to replace the stock shocks, as well as about 60 different part numbers for pretty much anything on the underside of the car that looked like it would wear out. 

Today Dad and I spent the afternoon getting the car up to working height on jacks (oh for a lift). Over the next few weeks we'll be dismantling, replacing/restoring and rebuilding. I'll be updating here as we go along. Hopefully in a few weeks time the car will be back on the ground and good to go for another 150,000 km :-)

For now I'll end with a pic of the car up on jacks.

IMG_0156_zpsltrpnvgv.jpg

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Update #1

The last couple of afternoons Dad and I have been busy disassembling the rear underside of the car.

Two days ago we removed all the underside trim, exhaust (sections 1, 2 & 3), heat shielding and the driveshaft. I'm really pleased to say that the underside of the car looks to be in really great condition in general. We were expecting to have rust clean-up and to re-paint the underside of the body, but it's really not going to be necessary. We'll give everything a full clean under there and touch up any spots that need it, but its looking good. :EWBTE-min:

All 3 hangers for the muffler are broken - I was anticipating that, so replacements are already on the way.

Here's one of the broken hangers - they've all broken in approximately the same place:

IMG_0159_zpskedzuc13.jpg

And here's a pic of the muffler out - lots of clean-up and polishing to be done!

IMG_0158_zpszazt0evf.jpg
 

We took the driveshaft out in one piece (e.g. we'll undo the universal joint at the CSB now that it's out of the car). The CV joint at the differential end looks and feels good. The guibo at the gearbox end is quite thrashed up (as they seem to be). I have a new guibo waiting to be swapped on, so that will be easy to fix.

One thing I was amazed by is how lightweight the CSB is! Even the way the CSB bracket is attached to the body of the car seems under engineered compared to the rest of the drivetrain. Presumably there isn't too much lash to control, so it doesn't need to be any beefier. 

I'll get some more pics today and add them in.


Then yesterday it was onto the rear axle and the rear subframe. We knew that the "quicker" way would be to drop the whole thing as one, but given we didn't know what we didn't know, and because we're not trying to turn this in to a race, we decided it was better/safer to disassemble in manageable parts. Turned out that this was probably a good idea, as we ran into various tool fitment issues in tight spaces, etc. 

*again, I'll add photo's in here, but was so busy/tired yesterday that we didn't get many as we were taking everything out.

We started with removing the brake callipers, as the brake lines are routed through the middle of the rear trailing arms. We then unbolted the shocks, lowered the hub assembly and popped out the springs.

With the brake lines, shocks and springs out of the way we then removed the bolts through the bushings of the control arms (at the hub end not the diff end), unbolted the rear trailing arm, the sway bar and the CV joint for the output shaft at the diff end, and lowered the hub assembly to the ground.

Having learned from doing the process on the driver's side (I have a RHD car, so driver's side is the passenger side for the USA) we made sure that we loosened every bolt before commencing disassembly on the passenger side. Our cunning plan to speed up removal on the passenger side came unstuck pretty quickly. The eccentric bolt that connects the lower control arm to the hub had rusted to the inner sleeve of the bushing, and although it was easy to get the nut off, we weren't able to slide (or forcefully encourage) the bolt out of the bushing.

We decided the best approach was to disconnect the lower control arm at the subframe end, something which we couldn't do until we had the diff out, as the bolt for the lower control arm can't be removed from the subframe until the diff is out of the way.

The challenge we had with taking the diff out (without the special tools) is getting access to the two bolts through the bushings on the rear of the diff, as well as the bolt through the front bushing. We were able to access the front bolt with an arrangement of a socket + universal joint + breaker bar. The rear two however necessitated loosening off the subframe bushing bolts and letting it drop by about an inch, so that the diff hung low enough to get to the rear bolts.

To drop the diff we removed the front bolt completely, and let the front of the diff rest on the subframe. Then the two of us held the rear of the diff, removed the bolts and then slid the diff back, and onto blocks of wood on the floor between us. The diff is pretty heavy, but definitely manageable between two people. 

The diff is weeping slightly around the input shaft seal, so will probably replace the seals while the diff is out. Then I won't have to worry about it.

With the diff out it was quick work to unbolt the lower control arm at the subframe, and get the hub onto the ground. Unbolting the subframe and dropping it was then easy, as all the weight was gone from it.

We were pretty tired at the end of the afternoon (my neck muscles are going to take a while to recover), but everything is now out at the rear and can be further disassembled and cleaned.

I'm sure we didn't win any speed records with the removal, but that's not the point. We both have a good understanding of it all now, and everything is safely out and undamaged. I think when it comes to reassembly we'll assemble the whole thing on the ground, and lift it back into place as one unit. Now that we know how it all fits, what order to do stuff in, and also importantly will be able to find centre of gravity more easily, it will probably be easier to put it back in as one piece, than it would be to reassemble it in pieces.

Today is a bit of a rest day, so I'm writing up the list of additional parts that we've identified that need to be replaced, and will get them ordered.

I'll take some more pictures and get them added to this post.

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Update #2

Sadly it's been a quiet few days on the car-front. My wife and I have both been sick (how do you even get a head cold in the middle of summer??). So I haven't been able to do any work on the car over the weekend.

That hasn't stopped dad though! :thumbs-up: He's been busy cleaning parts and prepping them for painting etc. From what I hear he's been polishing the muffler, cleaning underbody panels, suspension arms, etc.

He also cleaned up the rear brake callipers (apparently it took 4 lots of cleaning with various cleaning products to get all the brake dust and gunk off. He then cleaned them up with the wire wheel and has spray painted them with high-temp aluminium-coloured paint. Pics below - they're looking awesome. Will do the fronts the same, although I suspect I'll be on cleaning duty for them :rolleyes:

IMG_0164_zpsd2n9cvea.jpg

IMG_0161_zpsjm9wkys4.jpg

Obviously any important surfaces are masked here.

Over the next few days Dad is going to make up a set of washers, brackets, etc. for pulling all the various bushes. I'll try and get by after work a few days this week to do more cleaning etc.

Also placed the *hopefully* final order of parts tonight. I knew there'd be extra stuff to order, but wasn't expecting it to run to an additional 28 part numbers :(

Anyhow - that's it for now. Hopefully the next update will be along soon!

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Update #3

So unfortunately it seems that my car hasn't managed to avoid the RACP issues that the E46 seems to be susceptible to..

This is the front right mount...

IMG_0629_zpszgj6uqsl.jpeg

The rear mounts were foam reinforced by BMW NZ during the corrective action period, and they are indeed entirely free of cracks or damage.

It's only the front right mount which has cracks (probably due to the loading going onto that mount with the rear having been strengthened).

What is vaguely suspicious is that the front right mount has been painted black by someone at some point. I don't know whether they attempted some sort of repair on the cracks, or whether the paint was merely to cover over the evidence, but it does seem a bit odd. :dodgy:

It's a bit of a bummer, but not really a major (it was always going to be a bit of a waiting game to see if the RACP held up or not). Just means that now we'll need to drop the fuel tank so that we can perform weld repairs. (given it's only the front right that has cracks, and it doesn't have foam in it, it should be fine to weld-repair).

I'm also currently looking into options for plates to strengthen all 4 mounts further. Given the rear mounts have had the BMW structural foam done, they wouldn't be able to be welded, but having done quite a lot of research in the last couple of days, I'm leaning towards the epoxy method anyway for attaching the plates. Anyway - I still have some more research to do before making a final decision.

What this whole thing has highlight to me though, is just how glad I am that we're doing a full clean up, rather than just a whip the subframe out, do the bushings, and back in. The cracks were entirely imperceptible until the RACP had been significantly cleaned up. If we'd been in a hurry, and not checked properly, we'd have missed this, and then have had to have dealt with it down the road (possibly quite literally :lol:).

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Update #4

This week has been one of cleaning up parts for painting, cleaning up underneath the car, doing some prep for repairing the front right RACP mount, etc.

Last weekend while I was sick Dad cleaned up the muffler and gave it a polish...

Before:IMG_0158_zpszazt0evf.jpg


After:IMG_0177_zpstpcwc47t.jpg

After discovering the crack in the front right RACP mount, we dropped the fuel tank on Tuesday (more of a mission that we were expecting - none of the hoses were keen on letting go) in preparation for welding.

While I was at work, Dad sand-blasted one of the control arms to see how it would turn out:

IMG_0183_zpsmpxb0r2s.jpg

It cleaned up really nicely - so will sand-blast the other one as well and paint it the same aluminium silver colour we did on the brake callipers.

On Thursday after work we removed the upper and lower control arm bushings in the trailing arms using a puller set and a socket. Unfortunately not all of them are going to be as easy to do that way.

On Saturday Dad and I spent the day cleaning up underneath the car, cleaning the front right mount in preparation for crack repair, sanding parts ready for painting, and also removing the main bushing in the trailing arms (we went for the "use a hole saw to cut out the centre of the bushing, and then use a hacksaw blade to very carefully cut the aluminium shell of the bushing. This allowed us to relieve the tension enough to get it out fairly easily with the bushing puller, and a hole saw blade that was conveniently the right size :thumbs-up:).

I took the section 1 and 2 of the exhaust home to work on cleaning up in my spare time after work, etc. Below is an in progress pic showing one of the cats in the process of being cleaned up.

IMG_0184_zpsn0fxujoy.jpg

Next steps are to work out what subframe reinforcing plates we go with, or whether we fabricate our own. I'm also thinking that it may be worth doing the BMW structural foam in the front mounting points as well (This thread: http://www.m3forum.net/m3forum/showthread.php?t=440530 has a great discussion on how to do this).

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Update #5

Today was bushings removal day!

First up were the subframe bushings. During the week Dad had welded up a removal tool. Basically the same concept as the official tool. One end of the tool straddles the subframe surround, around the bushing. A high-tensile threaded rod goes through the bushing, and a plate on the other end of the bushing covers the end face of the bushing. Tighten up the nuts on each end and the bushing is pulled out.

Here's a pic of the tool (complete with demonstration bushing):IMG_0193_zpsue6k592p.jpg

And here it is in action:IMG_0196_zpsfk8ken3u.jpg

IMG_0198_zpsukesiqcu.jpg

We basically followed the TIS procedures for the various bushings. The tools that we made for this job mirror the official tools in the way that they work. As you can see in the second photo, we also heated the subframe bushing cages as per the TIS procedure (600C for up to 2 minutes).

Following this process the bushings came out in a reasonably straightforward manner. A fair amount of force needed (as you can see by the design of the tool).

Here's one of the bushings after removal. Not in terrible condition, but also not as great as the new ones going in.

IMG_0200_zpsw0rzfnkr.jpg

And here's the subframe, free of the 4 main bushings.

IMG_0199_zpsm1vpqzpd.jpg

:EWBTE-min:

Next up was the front diff bushing. Again, a very similar approach here. Just had to make sure we were accurate with the plate that cups the bushing, so that it was small enough to fit into the channel in the subframe, but large enough to cover the outer casing of the bushing.

Here's the tool mid-production:

IMG_0207_zpsmy2rbcqp.jpg

Dad driving his MIG welder, with plasma cutter in the background. Note that without this equipment (and a parent, or other acquaintance of your choice, who knows how to drive them), manufacture of said bushing removal tools would be very difficult.

And here's a couple of shots showing how the tool fits up.

IMG_0209_zpsskav4tut.jpg

IMG_0213_zpsld57b3gq.jpg

Note that after these photos were taken, testing proved that we needed to do double-thickness 10mm bar on the crossmember (like the subframe bushing tool) to provide sufficient bend-resistance. Goes to show just how much force is involved. That cross member is 70mm long, and ended up needing to be 20mm thick to take the forces involved!

I didn't actually take any photos of the diff mount bushing during/after removal, but rest assured that we got it out fairly easily.

We celebrated with lunch (which I didn't photograph, and won't show you, cause this is a car forum, not Instagram).

After lunch (which has already taken up too many words in this journal), we moved on to getting the bushings out of the inner ends of the upper and lower control arms.

We spent a while on this. The issue wasn't a mount for the side of the tool the bushing was being pulled towards, we were able to just use a large socket and some steel bar spacers for that (no need to weld up a tool), the issue was finding/manufacturing something the right size to cup the end of the bushing that was being pulled. We messed around with a few designs that we ended up abandoning, because we were in danger of flaring the ends of the aluminium sleeves on the bushings. We then tried just washers, and pulling only the inner core of the bushing, and letting it pull through the rubber. Again, in spite of a lot of force, we weren't able to make it budge even a little bit. At this point we consulted TIS procedure (and this awesome DIY: http://www.m3forum.net/m3forum/showthread.php?t=464146)  and determined that we were on the right track, and just needed to apply more force!!!

We wound it back up again, added a pipe extension to the breaker bar, wrapped the whole arrangement in welding gloves in case of catastrophic failure, and just kept cranking. Eventually it gave way, and, once it moves, it's fairly straightforward from there.

No photos of this bit unfortunately, we were a bit focused on not getting hit by flying bits of metal. But basically you just need more force. You have to get to the point where you cannot believe how much force is involved, and then go a few turns beyond that, and that turns out to be enough to make it move :thumbsup2:

Here's a photo magically showing the bushing removed:

IMG_0217_zpsnyzxnm0s.jpg

We tried the same approach with the lower control arms (using spacers to keep the two halves of the arm with the correct separation). We succeeded in moving the bushing somewhat, but there was so much force involved, and we had zero confidence in being able to reverse the process to get the new ones in, that we decided to cut our losses and buy new arms, which already have the bushing pressed in. At $50 each it's a pretty good deal, and given these are fairly lightweight parts, it's probably good to put new ones on (at least that's what we told ourselves as it got closer to dinner time).

Having already removed the trailing arm bushings a week and a half ago, that brings bushing removal to a closure for us. It's great to have got them all out. It's been really surprising just how much force is required to get the old ones out. Certainly without the ability to manufacture your own tools to get this job done, it would be either very messy and frustrating, or a costly process to get the bushings out.

Tomorrow will be a slower day. It's terrible weather here at the moment, so I'll limit myself to more clean up of the exhaust section 1 and 2.

Over the next few days Dad is going to clean up more parts for painting, and will paint as well if the weather starts playing ball and provides something less that 100% humidity.

Over and out for now.

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Update #6

So in spite of being an IS Project Manager for a living, and even though I should know better, this project is suffering from a moderate case of scope creep.

I've decided to add doing the rod bearings to this project. With the front of the car apart anyway for the suspension refresh it makes sense to do the rod bearings at the same time. The car has done 145,000km, and I was definitely wanting to do the bearings this year anyway, so it makes sense to do them at the same time. 

Doing that at the same time means that I'll have taken care of everything in Parts 1, 2 and 3 of this list with the exception of the cooling system and the fuel pump :thumbs-up:

It's going to be great to have all of the maintenance items up to date and to know that things like rod bearings are taken care of.

Place the final final order of parts today - up to 97 distinct part numbers. All OE with the exception of the koni shocks and some of the bushings (Lemfoerder).

Will do another update in a few days once we've made some more progress :arrow:

Edited by Karter16
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Admire your great attention to detail.

If you need advice or a repair kit for the subframe cracks give us a call.We had 40 kits of our own design made about 2 1/2 years ago and have 5 left. That means there are 35 E46`s out there with or reinforcement without any problems.

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Loving your 'do it once, do it right' approach.

 

What did you use to polish the muffler - it looks amazing!

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Fantastic. Love such attention to deal.

 

 

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4 hours ago, Karter16 said:

Update #6

So in spite of being an IS Project Manager for a living, and even though I should know better, this project is suffering from a moderate case of scope creep.

I LOL'd at this.... I'm also a PM for a living... Everything I undertake on my E30 is a textbook case of massive scope creep... and budget blow outs...  'while I'm in there' syndrome should be number 1 on my risk register haha.

Great that you are taking the time to refurbishing everything while you've got it out though! Looks brilliant :)

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Your Dad is awesome.

 

Can I borrow him??? :D

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6 hours ago, HELLBM said:

Admire your great attention to detail.

If you need advice or a repair kit for the subframe cracks give us a call.We had 40 kits of our own design made about 2 1/2 years ago and have 5 left. That means there are 35 E46`s out there with or reinforcement without any problems.

Thanks Ray!! Will do - we're taking a closer look this weekend - so will give you a call if we need some help :)

 

4 hours ago, zero said:

Loving your 'do it once, do it right' approach.

 

What did you use to polish the muffler - it looks amazing!

Thank you :) muffler was degreased, sanded with 1200 wet sandpaper, then an initial polish with jif, then a buffing wheel - it's basically a lot of hard work, but it does come up well B)

 

3 hours ago, Michael. said:

Fantastic. Love such attention to deal.

 

 

Thanks for the encouragement! Really enjoying the restoration process!

 

3 hours ago, jonoe30 said:

I LOL'd at this.... I'm also a PM for a living... Everything I undertake on my E30 is a textbook case of massive scope creep... and budget blow outs...  'while I'm in there' syndrome should be number 1 on my risk register haha.

Great that you are taking the time to refurbishing everything while you've got it out though! Looks brilliant :)

Haha I'm with you - at least we know how to recognise it right!! :P As long as I don't think about my bank account too much it all turns out fine in the end :wacko:

 

2 hours ago, Allanw said:

Your Dad is awesome.

 

Can I borrow him??? :D

:lol: Yeah he is a bit! I'll show him your post - he'll be chuffed! 

I suppose you can borrow him, but only after he's finished helping me with my car!!! :D

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HAVE ALL THE LIKES.

Great read, loving your progress.

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On 1/26/2017 at 7:16 PM, CSET said:

HAVE ALL THE LIKES.

Great read, loving your progress.

Awww shucks! thanks :-)

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Update #7

Yesterday Dad, a friend of mine James, and I made some more progress - specifically working on RACP reinforcement.

We did some investigation, and decided that we'd first try manufacturing our own reinforcement plates, see how difficult it was/how good the end product was, and then decide whether to put them on, or go for an out of the box solution.

Turns out making our own wasn't as difficult as we were anticipating...

We're manufacturing with 2mm steel plate, with the intention of epoxying the plates. Epoxy is a necessity on the two rear mounts, as they had the structural foam inserted by BMW some years ago. We were unsure as to whether we would weld or epoxy the front plates, but have settled on epoxying those as well, to get full adhesion across the entire surface.

In addition to this, on the front right mount (which had cracks in it) we will do the following:

  • Drill and weld the cracks (done)
  • Cut through from the top to check that the bolt carrier hasn't detached from the upper layers of the RACP (and fix if it has).
  • Structural foam for the front two mounts.


All of those measures in combination should be sufficient to remediate the existing damage, and prevent damage from reoccurring. I don't intend to track the car or do anything else that is likely to cause extreme stress to the RACP. I'll have to monitor it over time, but I expect this work to vastly improve the current situation.

We started by firstly cleaning the underbody protection and paint off the entire surface area of the RACP that we're going to reinforce, and then we used thin cardboard to make a template of each surface we want the plates to cover.

For the rear mounts this resulted in a set of templates that looked like this:

IMG_0226_zpsdqgwae7j.jpg

We then transferred the templates onto the sheet steel (this pic show's only one of the elements of the rear plates):

IMG_0227_zpsvzxslr74.jpg

We used the plasma cutter and cut each rough shape out, cutting outside of the markings. (note this is a different part to the above photo!):

IMG_0241_zpsvym1dpro.jpg

We then cleaned up each piece on the bench grinder, using the marked template to show where to clean the edges to.

There was a little bit of back and forth, making minor adjustments so that the pieces all fitted and sat correctly, then we held the pieces in place, and tack welded them in place:

IMG_0228_zps6rotqvjy.jpg

This resulted in something that looks like this:

IMG_0240_zpsbtj9jrwl.jpg

Next steps on this example are to brace it, weld the joins and clean the piece up. Once that's done, the various holes that need to be drilled will be done, and the piece should be ready for fitting.

The other rear plate is a mirror image of this one, with a couple of extra holes drilled in it for various cable brackets. The two front ones are unique, as one has more scallops in it than the other.

Overall I was pleasantly surprised at how easy this whole process was. Going into it I wasn't sure what our end product would be like and whether the fitment would be exact enough, but it's turned out very well indeed. :thumbs-up:

Next steps are to finish the other brackets and weld and clean them up.

In other news, we've been continuing to clean pieces up for painting. Had one of my orders from Pelican Parts turn up the other day. Another in transit, and the last one is pending a couple of not in stock items before it ships.

Till next time :ph34r:

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Very cool project. Love to see these in the hands of enthusiasts more and more.

I actually nearly bought this, except for the fact I couldn't work out a fair trade value with the seller with my trade in. Didn't actually see this in person at all before it was sold. Very good purchase and love the project.

I must add, and many who have spoken to me in person on a personal level will know this, that I am not a fan of the plate method "fix" for the rear floor, expoxy or weld. To me it does not fix the problem, it simply transfers the load to the next weak spot in the chassis - inner wheel well and further up the stream. Once these fail your car is basically harder to fix or beyond economical repair. The fact that the official epoxy properly applied showed that it stopped further failure proves what I have been saying for many years about this issue.

Sorry Ray, but I do opinion differently about this issue than you. I do agree however if there are cracks already beyond the 25mm limit set by BMW then a plating repair is a must short of a floor replacement. 

keep up the good work!! Love where this is heading

Edited by M3_Power

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2 hours ago, M3_Power said:

Very cool project. Love to see these in the hands of enthusiasts more and more.

I actually nearly bought this, except for the fact I couldn't work out a fair trade value with the seller with my trade in. Didn't actually see this in person at all before it was sold. Very good purchase and love the project.

I must add, and many who have spoken to me in person on a personal level will know this, that I am not a fan of the plate method "fix" for the rear floor, expoxy or weld. To me it does not fix the problem, it simply transfers the load to the next weak spot in the chassis - inner wheel well and further up the stream. Once these fail your car is basically harder to fix or beyond economical repair. The fact that the official epoxy properly applied showed that it stopped further failure proves what I have been saying for many years about this issue.

Sorry Ray, but I do opinion differently about this issue than you. I do agree however if there are cracks already beyond the 25mm limit set by BMW then a plating repair is a must short of a floor replacement. 

keep up the good work!! Love where this is heading

Thanks very much :-) Haha I guess I'm lucky you didn't buy it then! :P 

I agree with you on the RACP plates approach. Same as you, it seems to me that you're just pushing the load somewhere else onto the panel. The excessive load isn't going to just disappear when the plates are added. I think that the structural foam injection approach can help spread the load over a wider surface area (as well as increasing structural rigidity between the layers). For me, with cracks in the front right mount, the plates are a bit of a necessity, if nothing but to hold all the pieces together :blink:

Thanks very much for the encouragement - means a lot coming from someone with so much experience with the E46 M platform!

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Update #8

So after a week of backwards and forwards to hospital with my wife, wife is now better and Dad, James and I spent yesterday making more progress.

First up was finishing up the RACP reinforcement plates.

We tack-welded the second rear plate, and then seam welded both of them up.

The two front plates were just simple bends. We measured the fold lines and were able to manually fold the two front plates :thumbs-up: the folds ended up perfect, no gaps at all around the arc of the curve.

With the plates welded / folded up, the next step was to drill the holes for the mounting bolts. Obviously it's important to get these in exactly the right place, so that the hole can be no larger than necessary for the bolt to fit through (i.e. enlarging the hole to allow for imperfect fitment, is then not supporting the mounting bolt as well as it could).

A brief discussion around how best to do this led to Dad's excellent suggestion of using a laser sight to mark the centre of the hole.

We rigged up the laser level like so:
IMG_0269_zpsnaduppgw.jpg

A piece of masking tape across the hole lets us align the laser dot correctly.
IMG_0271_zpsbigusj4m.jpg

We were then able to locate the plate, and mark the plate where the laser dot fell.
IMG_0268_zpswrsdpbbk.jpg

With the holes drilled we have a set of 4 completed plates:
IMG_0279_zpsknw6pfvn.jpg

Here's how they look sitting on the RACP. (Note: Only showing three, as the two rear ones are essentially a mirror image of each other.)
IMG_0272_zps64bczy6d.jpg

IMG_0277_zpsp0ipkqig.jpg

IMG_0274_zpsp04rh9r3.jpg

The last items to manufacture are the two small plates for the diff cradle. They're pretty straightforward, small flat spacers with two holes drilled in them. Here's a token picture of their manufacture to prove that we made them.
IMG_0262_zpshuxuzu5c.jpg

That pretty much brings to a close the manufacturing stage of the plates. They will of course get a final clean up prior to being epoxied on, but there's no point in doing that until directly before they're going to be affixed.

I've got the 3M 8115 epoxy on order. Rather than paying for the special applicator gun, we'll just modify a standard caulk gun. Provided the epoxy arrives this week we'll look to attach the reinforcement plates next weekend. :thumbs-up:

After finishing up the plates, we split up, Dad and James took on changing the diff seals, and removing the rear cover so that it can be glass bead blasted to clean up the aluminium fins.

The diff looks to be in pretty good condition.
IMG_0280_zpsib8ejlqo.jpg

IMG_0281_zpsxfaj6wgb.jpg

With new seals and some new oil it should be good to go :angel:

While Dad and James did the diff, I armed myself with some degreaser, and scrubbing brush and a towel and got to work cleaning up the underbody. It's pretty tedious work but the upside is that it cleans up really nicely. I got through the two rear wheel wells with the degreaser, and did one well with kerosene to take the tar spots off. Unfortunately the photo below shows the wheel well that hasn't been kerosene'd (the lighting didn't allow for a decent pic of the other well, so just imagine the below, without the tar spots :EWBTE-min:).

IMG_0284_zpsghu6k7xw.jpg

I'll do more degreasing and cleaning up after work during the week, and then next weekend we'll hopefully be ready to epoxy the plates and commence reassembly of the rear axle. We're going to build it up and then lift the entire thing into place at the end. This is preferred for a couple reasons. 1: easier to work on, 2: allows us to work in parallel while the epoxy plates are curing.

We'll also be starting on disassembly of the front suspension in the near future, as there will be some lead time on cleaning and painting parts etc. that we want to get a head start on.

Starting to feel like it's all coming together! :rolleyes:

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Awesome work!

Did you keep the templates for the strengthening plates - I would be keen to build my own.

Are you strengthening other areas as well, like the front subframe around the engine mounts and the rear trailing arm mounting points?

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Any reason for using the 8115? Wouldn't have been my choice as it's a panel bonding adhesive and not structural or impact resistant unlike the 7333 or 57333 used in a lot of dissimilar metal bonding application. I can't remember how heat resistant it is either ... might be something to consider given how close it is to the exhaust?

Edited by M3_Power
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11 hours ago, M3_Power said:

Any reason for using the 8115? Wouldn't have been my choice as it's a panel bonding adhesive and not structural or impact resistant unlike the 7333 or 57333 used in a lot of dissimilar metal bonding application. I can't remember how heat resistant it is either ... might be something to consider given how close it is to the exhaust?

Well interestingly because every example I've seen of people epoxying the plates, they've used 8115. I did have a look through the 3M catalogue, but must have missed 7333. As you say it certainly seems to be a much better option for the reasons you point out.

I think I'll be sending the 8115 back and be getting 7333 instead. Thanks very much for bringing this up - really appreciate it!!

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So today was pretty much 8 hours scrubbing parts to clean them up :AreYouSerious-min:

Dad and James disassembled the drive shaft and cleaned it up ready to be painted. They cleaned up the second of the trailing arms ready for painting, and Dad cleaned up the diff (which is actually looking in such good condition paint-wise that it probably won't need to be repainted).

They then spent some time in the afternoon welding up the frame for a trailer that James is making.

Meanwhile I spent the whole day cleaning the following:

 - The black plastic under-tray pieces
 - The exhaust heat shielding
 - The exhaust support brackets/plates

Wow that's a depressingly small list when it's typed out :cry-min:

The reason it took so long is that the plastic under-tray pieces looked like this:

IMG_0295_zpsbmjfunwy.jpg

It appears to be the under-body protective coating stuff (or something like that). with tar and rubbish all caught up in it.

Basically the cleaning process was:

  1. Quick scrub with sugar soap to get dirt and grime off.
  2. Soak with acetone to make the protective coating go brittle.
  3. use a paint scraper to scrape off the thick gunk.
  4. use a cotton towel and more acetone to remove the remaining residue.
  5. polish up the black plastic with plastic conditioner.

Unfortunately I forgot to take a photo of one of the finished pieces, so I'll get one and add it in here.

My arm is now sore from all of the scrubbing, but it was worth it to clean everything up properly :thumbs-up:

I'm still waiting for some parts to arrive, and I'm also waiting for the epoxy for the RACP reinforcement plates.

On the epoxy. I had ordered 3M 8115 because that's what everyone seems to use. However after I had ordered it, M3POWER suggested that I use 3M 7333 instead. 7333 is similar to 8115, however it has the following benefits:

  • It is rated a "structural" adhesive by 3M.
  • It's impact resistant.
  • It is high temperature resistant.

Based on the recommendation and my own research I decided to order 7333 to use, and I'll be returning/selling the 8115. I'm very happy that this option was pointed out to me before I'd done the plates. I had looked through 3M's catalogue before ordering the 8115, but must have missed seeing 7333.

I'll give an update on how the 7333 goes when I do it :thumbs-up:

During the week Dad is going to paint the remaining parts:

  • Drive shaft
  • trailing arms
  • exhaust support plates
  • exhaust heat shielding

Hopefully everything has arrived by next weekend and we can epoxy the plates, and I'll finally be able to take a photo of all the new parts laid out :MotherOfGusta-min:

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Update #10

Not a major progress update this weekend. Still waiting on some parts (particularly the 3M 7333 epoxy).

While we're waiting for the epoxy we've been continuing with clean up and painting. I'll do a set of photos of all the parts we've cleaned and painted once they're done, so don't have any photos for now.

Today Dad and I did the seals on the output shafts of the diff, finished preparing the trailing arms for painting and experimented with various brass wire brushes for cleaning up the tricky corners on the exhaust.

The last few parts and the epoxy should arrive this week, so we should be able to get stuck into epoxying the plates next weekend.

In the mean time here's a photo of all the new parts laid out (gotta feel like I'm getting my money's worth!) :wub:

IMG_0305_zpsldyqrsqj.jpg

And here's an overhead shot for good measure
IMG_0308_zpsnno0ejcd.jpg

As I said, there's still a few parts on the way, so they haven't made the pic. Those items are:

Guide Bushing Repair Kit x4
Caliper rebuild kit front left/right x2
Caliper rebulid kit rear left/right x2
Steering guibo x1
Salmon Relay x1 (cause SMG)
Transmission bearing set x2
Hex Nuts x4
Section 1 to Section 2 Gasket x2
Exhaust Hangers x3

Till next time :arrow:

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Update #11

So last weekend we didn't get too much done. Dad and I went to the Bruce Springsteen gig in Auckland on Saturday night :wub: SO GOOD!

We did get a few bits and pieces done before we went...


We swapped out the transmission mounts, and took the opportunity to clean up the support bracket, etc. at the same time.

Here's the bracket and mounts as they came off the car:

IMG_0315_zpsek7kknor.jpg

And here's a pic of the bracket & mounts back on the car. Bracket was bead-blasted to clean it up, and the mounts are new:

IMG_0319_zps5grdyr6q.jpg


The second thing we got done was fitting the new seals on the diff and reassembling. The diff body has been painted, the rear cover has been bead blasted, and in the input and output flanges have been painted as well:

IMG_0383_zpsqidanc8o.jpg

IMG_0384_zpsdiuips5a.jpg


And today was RACP reinforcement plates day!

First up we did a test fit of all components, and a dry run through of the process.

Then we started with cleaning up the surfaces that the epoxy will be applied to.

We put the finished plates into an acid pickle:

IMG_0339_zpssebdown9.jpg

While the acid did its work we got onto cleaning the RACP. The mounting areas had previously had the paint and underbody protection cleaned up as part of the manufacture of the plates, but they still need a final clean up before they're ready for the epoxy.

We cleaned up the surfaces with a sanding disk on the die grinder, and then cleaned the surface with 5 rounds of kitchen roll and acetone (ensuring to clean from the centre out, so as to not drag dirt from the edges onto the clean surface.

IMG_0344_zps6ucpbcvi.jpg

You can see in this photo that there is some residue from the paper towels, we used a lint-free cloth to clean off this residue and finalise the surface. Below is a pic of one of the mounts after cleaning with the lint-free cloth.

IMG_0348_zpsvnc9ta33.jpg

We then put together a custom adapter to be able to use the 3M 7333 2-part epoxy with a standard caulking gun. The adapter is simply a plate with two pieces of rod welded to it, along with some washers to spread the load, and a second plate to add reinforcing to the arrangement.

Here's a couple of pics showing the design and assembly.

IMG_0342_zpsbzqhkctb.jpg

IMG_0343_zpsj9sicosc.jpg

While we were working on cleaning the RACP surfaces and building the caulking gun adapter the acid pickle was doing its work.

IMG_0341_zpsaop7bkfd.jpg

With the pickling complete, we neutralised the acid with baking soda, and dried the plates.

IMG_0352_zpsv63njpcz.jpg

IMG_0353_zpssjbq85dz.jpg

Next up was to apply the epoxy. We were pleasantly surprised at how well our gun adapter worked. Here's a photo of it being prepared for use.

IMG_0355_zpso1z1omla.jpg

The epoxy nozzles are seriously cool, the way they're designed to mix the two parts of the epoxy completely really makes the whole process a lot quicker and easier.

With the surfaces fully cleaned and prepared, the process we followed to epoxy each plate was as follows:

1: Apply epoxy to the plate, and spread using the supplied brush. We applied an even layer (The consistency of the epoxy makes it easy to spread, and makes the appropriate thickness fairly self-explanatory). Note that we didn't brush to the very edge of the mounting hole, as we wanted to ensure that we didn't end up with too much epoxy squeezing into the hole when we clamped the plate in place.

IMG_0359_zpsnn3sk558.jpg

2: Apply epoxy to the RACP surface. Applying the epoxy to the vertical surfaces isn't too bad, it sticks pretty well and can then be spread by the brush. We found with the horizontal surfaces that it was best to follow the nozzle fairly closely with the brush, doing an initial spread of the epoxy as we went, to get it to stick to the surface and not drip. :thumbs-up:

IMG_0361_zpsyjhyecyj.jpg

IMG_0362_zpsavey8rga.jpg

3: Apply an extra bead of epoxy to the plate along large surface areas, etc. and in places where the may be a slightly larger gap (e.g. around curves, etc.).

IMG_0364_zpssghjsred.jpg

4: Mate the plate to the RACP, and bolt it up (we partially greased the bolt thread, in case we had a lot of epoxy spillage into the bolt carrier. We were careful to not get the grease anywhere near the bonding surfaces). Note that we manufactured clamping plates out of 5mm sheet steel, to act as large "washers" and spread the clamping force of bolt out over the surface.

IMG_0365_zpsspo41eud.jpg

5: We then did the same with the rear mount on the same side (as we would add further clamping and bracing in pairs.

IMG_0367_zpsdkizrvtf.jpg

IMG_0375_zpsg3sqrzdo.jpg

IMG_0370_zpsutwpaj9j.jpg

6: We then added additional bracing using strategically cut pieces of timber.

IMG_0382_zpsnf2iduvl.jpg

7: With the plates well clamped in place, we then removed the bolt for each plate in turn, and ensured that it wasn't going to end up getting epoxied in place from the epoxy that had been squeezed into the bolt carrier. Fortunately we'd judged the spread well, the epoxy and spread to the inner edge of the bolt hole, but hadn't pooled in the bolt carrier. We cleaned up the thread and re-greased the thread and tightened it back up. We also took the opportunity to clean up any epoxy that had leaked out beyond the bead, and we inserted sheet plastic between the 5mm clamping plates and the reinforcement plates, so that we didn't accidentally end up with things epoxied to other things they shouldn't be! :rofl3:

IMG_0379_zpsqbsra85g.jpg

IMG_0381_zpsynrvpea1.jpg


And with that we were done! The plates are all epoxied, and clamped/wedged in place. We've got good beads all the way around on the plates, and not too much excessive spillage.

We found the whole process easier and quicker than we were expecting. The 3M 7333 epoxy is really great to work with. The mixing nozzle is awesome, and the epoxy is easy to spread and work with. The long work time also helps a lot. :thumbsup2:

The clamp time is 8 hours, but we're in no rush, so it will stayed clamped until some time tomorrow. Dad has been loosening and retightening the bolts every couple of hours just as an extra check - would be a shame to have a :facepalm: moment at this point!

The epoxy turns purple when it's cured. When I left my parents place this evening the epoxy was already starting to turn purple B)

Tomorrow will be more cleaning on the underbody, as well as clean up, seam sealing and undercoating the plates.

Good day's work!

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