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aja540i

S85 rod bearing replacement

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I am getting ready to have the rod bearings replaced in the M5 as i am on borrowed time with them (157000 kms), looks like there are plenty of options for getting the parts at a reasonable price, but i doubt BMW will be interested in doing the work if i supply the parts, so i am hunting for a reputable shop to do the deed. I have seen Taylor automotive mentioned a few places and am wondering if anyone has any first hand experience with them good or bad? PM me if you don't feel comfortable mentioning here. I have also asked BMW for an estimate for the whole job.

I am probably going to use the BE bearings replacements as i will be monitoring them with oil analysis at every service and they use a copper/ lead bearing surface which gives plenty of warning of impending doom, the new BMW bearings are aluminum/ tin which don't.

I am also going to try and sneak a power pulley kit past the accountant at the same time.... ;)

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BM Workshop outsourced some of the engine work on my N55 to them, I can see it on the invoice. Going by the invoice: head bolt thread repair, head gasket replacement and cylinder head inspection. 

It's still running perfectly several thousand km later so I guess they're ok :)

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It also might pay to give Kayne Barry a call. He might not be the best person to do it, or even be in a position to do it at all but it's a sure bet he'll be able to give you some reliable recommendations.

On the other hand, if BM Workshop are happy to use Taylor Auto then that's a pretty good endorsement.

 

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+1 for Taylor Automotive

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I have found a willing mechanic (that i trust) and ordered parts from Turner motorsport, about $2500 NZD all up. Once bits arrive it will be off to the mechanic to spill its guts. Only 1 person i contacted apart from BMW was willing to do the work which surprised me, it is a fairly basic bearing replacement and it has been done by a lot of people but it seemed to scare everyone i spoke to. Once it has been done and i do a few running in donuts it will be getting an inspection II at BMW, and i will be doing oil analysis at every oil change to monitor condition.

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Good idea re oil analysis, I've just started doing such on my 3UZ soarer to see whats going on with the Penrtie 5w-30 Race 5 oil I run, after 4500km / 6 months it was showing 10 ppm copper, all the other metals less than that. 

Only anomaly was 79 ppm Silicon (Si) content, but I think this was from the old container I used, so next time I'll be sure to use clean new stuff for the next sample.

I used lubenz.co.nz $66 for the sample test. 

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I used Gough, $49. Includes postage. From memory my copper was about 7 ppm, but lead was up around 28.

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Big ol' box of goodies arrived on doorstep yesterday, now to open the motor up and tip them in....DSC_0427.thumb.JPG.e7e2398f3ad26a0ab44b3041029598d7.JPG

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2 hours ago, aja540i said:

Big ol' box of goodies arrived on doorstep yesterday, now to open the motor up and tip them in....DSC_0427.thumb.JPG.e7e2398f3ad26a0ab44b3041029598d7.JPG

nice , you doing the vanos oil lines up the front of the engine while your in there?

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The one that lives in the sump is getting done, will probably do the others when the next thing needs replacing.

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Car is on a hoist with all the paraphenalia removed to allow the sump to fall off, found a leaking power steering hose so that is on its way from Germany, power pulley arrived yesterday so will be fitted at the same time, should help with the running in donuts! Also noticed some tired bushes in front suspension but will get those replaced at next service after bearings are run in.

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So, apparently got to this just in time, very light scoring on the crank but not enough to worry about, lower oil pump chain guide broken but still in place, bearings well used...

DSC_0464.thumb.JPG.7c0f802899edd1228c8c845e056f3a37.JPG

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How many kms has your car travelled?

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How many layers of the bearing had been worn down? Looks like a few! 

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You're going to be able to drive it like you stole it for another 150k soon!

 

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2 hours ago, Lubed said:

How many kms has your car travelled?

About 160k.

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43 minutes ago, Michael. said:

How many layers of the bearing had been worn down? Looks like a few! 

I belive the copper Is the first coating layer on the base metal, then lead, then a teflon type material, so almost through 3 layers In places.

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Fascinating. 

I guess there is only so much oil can do when dealing with a 11 year old well used machine that has the most race like engine in a 'common' road car.

It would be interesting to see how good one of these engines would be if perfectly treated very time it was warmed up, driven, had oil changes etc. 

 

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From what I understand the main issue is the size of the bearings, they have a very small surface area when compared to bearings from more run of the mill engines, and given that the red line is 8250 rpm they cop a bit of punishment. I have seen pictures of worse bearings from much lower mileage cars, so mine has probably been treated better than some, one careful lady owner, only driven to church on Sunday etc! ;)

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Interesting.

Would it be safe to say the bearing cops more pressure with less surface area? 

Or is it more along the lines of less surface area equates to higher temperatures on the bearing surface?

 

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12 hours ago, aja540i said:

 so mine has probably been treated better than some, one careful lady owner, only driven to church on Sunday etc! ;)

I can personally vouch that this car has NEVER been over the legal open road speed limit...

... in my driveway.

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2 hours ago, Allanw said:

I can personally vouch that this car has NEVER been over the legal open road speed limit...

... in my driveway.

yet...

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18 hours ago, Michael. said:

Interesting.

Would it be safe to say the bearing cops more pressure with less surface area? 

Or is it more along the lines of less surface area equates to higher temperatures on the bearing surface?

 

A bit of both i think, its harder to maintain a good oil film between the bearing and crank with higher pressure due to smaller surface area, which in turn leads to higher temps and contact between the surfaces. I think over all BMW did a pretty good job with the lubrication system on this motor, but there are always compromises when you are designing an engine to sell to the public. Also this engine was designed using their experience with their F1 V10, and none of them were expected to do 160,000 km !!

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Yeah I agree completely. 

And once it's built and sold it's out of their hands for well they are treated.

The life of the engine is always going be shortened by:

  • Driving hard during cold starts
  • Wrong oil grade / additive specifications
  • Unsuitable fuel types 
  • Infrequent oil changes, duration or mileage
  • Air and oil filters being neglected, or not OEM spec.
  • Track racing is naturally hard on an engine 

and other stuffff

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Can we all do skids with it to break them in?

#RaDzSkDz

 

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