Mo

[cleanish_e46 207]

G'day,

I thought I'd start a project journal on here.

Picked up a 1986 BMW 320i. In a bit of a state, but WoF and Rego. A good starting point for the price.

Priority is the original M20B20:

Cylinder 1 - 160psi

Cyinder 2 - 150psi

Cylinder 3 - 95psi

Cylinder 4 - 70psi

Cylinder 5 - 120psi

Cylinder - 6 160psi

So not ideal, but I'd like to rebuild it if I can. Hoping it's just a head gasket and not the head, we'll see. This is the first time I've pulled a head off so any advice is appreciated.

Enjoyed working on stuff with my grandad when he was alive, but wasn't my old man's thing. I've got a son due in October and would love to know what I'm doing by the time he's ready to pick up a wrench, so I bought this to teach myself, and get back to doing something I love.

Chur,

Josh

[Ghost Chip 188]

Congrats on the pickup. Hopefully it’s a good base. Even comes with the original black plate. Can’t wait to see it tidied up.

[cleanish_e46 207]

Cheers mate, I hope so too. The plate was part of its appeal for sure. 

[KwS 2425]

I was wondering where that went. Saw it on facebook in various states of disrepair. Its a shame the previous owners molested it as the old photos of it I found actually show it looking quite good. https://autoinsiders.co.nz/autofair/sales-ad/9696/BMW-320i-1986

Hopefully it wont be too much of a mission to get it back into shape. I think I saw it mentioned the engine had been well and truely cooked?

[cleanish_e46 207]

Cheers for the photo's Kelvin, certainly looks better there. I didn't pay that much which is a good thing. 

Wouldn't be surprised judging by the symptoms. I did drive it home from the seller's house to my in-laws where it spat out a little coolant from the overflow. Did a run around the block a few days later and was misfiring so gave her a tickle up on the driveway before driving to my place and parking her up in the garage, temp gauge was just starting to climb after twenty minutes of highway speeds. 

I'll rebuild if I can, but if not will look at options regarding an engine swap. 

[cleanish_e46 207]

Slow progress, but made a start and got my project and tools back in the same garage. 

I’ve lined up a healthy M20B20 to swap in while I rebuild the original.

Any advice on changing from L-Jetronic to Motronic would be appreciated. I’m not trying to make an L-Jet engine run on Motronic, but swap a Motronic engine into a pre-facelift car. 

Cheers. 

[cleanish_e46 207]

Got this much done tonight.

Intake, exhaust and head bolts and she should be out. 

Bloody good to get wrenching again. 

[cleanish_e46 207]

Got there tonight.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Couple of nuts seized on the exhaust manifold, but not bad for thirty-five years old. 

Above: Head gasket is in one piece, but absolutely covered in sealer. 

Above: As is the head. What's the best method for cleaning it out of all the coolant passages? The two head bolt holes on the right-hand side of this image (cylinder six) were full of oil, none of the others were. Is that normal?

 

Above: This head bolt hole between cylinders one and two was really dry and full of powder, I have no idea what it is or why, can anyone help?

Above: This scratch was the most concerning issue, on the intake side of cylinder one. Looks like a scratch rather than a crack. Can't be from removal tonight as I hoisted the head in one go and gently lowered it onto a couple of blocks of wood so the head wasn't resting on the valves. There's no corresponding marks on the block. 

Any advice is really appreciated as I haven't done this before. 

Cheers.

[KwS 2425]

Out of curiosity, is there a corresponding mark on the headgasket where those gouges in the head are? One looks like it leads right to a coolant gallery. 

[cleanish_e46 207]

Had another look this morning, the rings on the gasket are intact but the gasket looks blown around where that mark would be. That being said, cylinder one had the most compression out of the six…

[cleanish_e46 207]

Spent a bit of time in the workshop over the weekend. Exhaust manifold came off with a bit of pursuasion.

Picked up the tools I didn't have and disassembled the head. 

All the internals looked in good order and have been set aside for when it's time to rebuild. 

 

Having trouble getting the studs out that the thermostat housing mounts to, but started cleaning the head up, no signs of excessive wear, will get it to an engine specialist when I have time and see what they say about the scratch. Hopefully it can be fixed and reused. What should I be asking for? Clean, crack test and resurface?

In the meantime, I'm interested in learning how I can get the most out of this M20B20 before I rebuild it so I'd appreciate any suggestions people may have.

Been good fun so far and quite rewarding. 

Edited August 15, 2021 by cleanish_e46

[cleanish_e46 207]

I did get the head to a shop… the day before lockdown! 
 

I’ve been doing what I can with all this time we have on our hands, but not having the head back has slowed things down. 

 

Boredom got the better of me and so I started removing some of the ancillaries to give the engine and bay a good scrub. 

 

I think I’ll replace the engine mounts while I’m at it. 
 

I hope everyone’s cracking on through lockdown and keeping well.

[cleanish_e46 207]

A bit more done. Got the crank bolt off by jumping the starter with a screwdriver. Going to clean the block and do the seal while I’m in there. 

[cleanish_e46 207]

On 8/11/2021 at 8:24 PM, cleanish_e46 said:

Got there tonight.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Couple of nuts seized on the exhaust manifold, but not bad for thirty-five years old. 

Above: Head gasket is in one piece, but absolutely covered in sealer. 

Above: As is the head. What's the best method for cleaning it out of all the coolant passages? The two head bolt holes on the right-hand side of this image (cylinder six) were full of oil, none of the others were. Is that normal?

 

Above: This head bolt hole between cylinders one and two was really dry and full of powder, I have no idea what it is or why, can anyone help?

Above: This scratch was the most concerning issue, on the intake side of cylinder one. Looks like a scratch rather than a crack. Can't be from removal tonight as I hoisted the head in one go and gently lowered it onto a couple of blocks of wood so the head wasn't resting on the valves. There's no corresponding marks on the block. 

Any advice is really appreciated as I haven't done this before. 

Cheers.

I reckon that powder is casting sand?!

[cleanish_e46 207]

Interesting development today.

I have been looking for a manual conversion since I bought the car. Long-term goal was to pair that with a B25, and long long-term goal was a stroker build once my knowledge and pocket allowed.

 
Happened across this old girl a couple of weeks ago. NZ new, factory manual 325i. Needs some interior bits and minor rust patches, but starts and runs well. Expected it to be good for a donor, but after chucking it up on the hoist, she’s really not that bad. 

Justified the purchase by picking it up for what the engine and box would set me back in this market. Happy days. (Much needed after lockdown). 

Another one to save! 

[cleanish_e46 207]

I've been having a closer look at this since Project Mo has stalled with the B20 head still at the machine shop.

 

Came across an almost complete factory toolkit and service booklet with stamps from new until about 10,000km ago.

Almost everything that appeared to be missing has shown up in the glovebox / footwells / under seats or in the boot. 

Short of the E30 M3, this is a dream project for me and brings back a lot of memories of watching the British Touring Car Championship with my dad at Silverstone. Just opening the garage door is enough to put a smile on my dial at the moment...

Edited September 24, 2021 by cleanish_e46

[cleanish_e46 207]

Not the morning I needed after working on my house yesterday. In the few hours I was away last night, someone broke in and stole all my tools that are worth stealing. 

Not ideal. 

Anyway, the 325i. 

Replaced the leaking fuel hose and while I was under there jacked up the transmission and tightened a loose mount. 


 

The sunroof was sealed shut and to be fair to whoever did it, they’ve done a good job of keeping the elements out. Was a bit concerned about what it was going to look like but it’s pretty good. 


 

I’m not absolutely sure what’s missing but I know the left and right gates are broken and drive cable is missing so sing out if you know where I might source these. 

Onto the worst of it now. I started sanding around a couple of holes in the rear valance. Those couple of holes are now several, but I expected that. At least it’s easily accessible and so far I haven’t found any rust anywhere else. Will cut out what’s no good and weld some new stuff in. 

[cleanish_e46 207]

Got the head back today:

Tank cleaned, crack / hardness tested and resurfaced at Engine Specialties in Glenfield.

[cleanish_e46 207]

Made a start on the rust on the 325i today, we’ll call her Goldie for now. 

Pretty solid behind the bumper.

Not so much beneath the battery.

One patch.

Two patches. This one is the niggliest. Nothing too horrific though, and everywhere else looks solid.

[jon dee 500]

On 8/11/2021 at 8:24 PM, cleanish_e46 said:

 

Above: This head bolt hole between cylinders one and two was really dry and full of powder, I have no idea what it is or why, can anyone help?

Fretting corrosion will produce "powdered rust" in a dry environment. In a wet or oily environment it will make rust coloured mud. However for fretting corrosion to occur in that tapped hole the bolt would have had to be loose enough to allow some small relative motion between the male and female threads. Like loose enough that the load would come off the thread after a combustion stroke and then and then be re-applied with the next combustion stroke. Seems unlikely though as I would have expected the head gasket to have blown if the head was lifting that much.

Try finger threading a head bolt into several of those tapped holes and see if the dry one feels a bit looser than the others.

Cheers...

[cleanish_e46 207]

6 hours ago, jon dee said:

Fretting corrosion will produce "powdered rust" in a dry environment. In a wet or oily environment it will make rust coloured mud. However for fretting corrosion to occur in that tapped hole the bolt would have had to be loose enough to allow some small relative motion between the male and female threads. Like loose enough that the load would come off the thread after a combustion stroke and then and then be re-applied with the next combustion stroke. Seems unlikely though as I would have expected the head gasket to have blown if the head was lifting that much.

Try finger threading a head bolt into several of those tapped holes and see if the dry one feels a bit looser than the others.

Cheers...

Cheers for that John, does seem unlikely as you say, but still haven't figured it out to be honest.

I'll try that.

[cleanish_e46 207]

Pulled the interior out this afternoon and found a wee hole in front of the driver's seat. Solid everywhere else, just spots of surface rust to be sanded. 

Will have to strip this back to find out how bad it is, but it's in a relatively flat spot so should be an easy patch.

[cleanish_e46 207]

Long story short: a pipe burst at home and for five minutes a lot of water covered everything in the kitchen and garage below. 

The seats were out, but the passenger footwell was soaking. Carpets had to come out, can't have that foam underneath holding water in the car. .

Everywhere is solid, so there's the silver lining. 

[Ghost Chip 188]

Sorry to hear mate! Electronics alright?

[cleanish_e46 207]

Hope so @Ghost Chip fortunately I had covered the block and taped up all electrics as I went. I think the carpets copped the worst of it.