Bought an old BMW M3, filled with regret...

mrk

mrk

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I've asked them, but main (little end) bearings aren't prone to failure as there's no wear under normal conditions. The conrod (big end) bearing shells are designed to wear but once the material starts to be worn through, debris starts to damage the crank journal because of the reduced clearance, or old thick oil etc. If the tabs on the shells wear or the shells bend, then they will spin causing major damage leading to needing a new crankshaft and the rest of the kit, or a new (used) engine with new shells and bolts fitted.

Even more reason why the connecting rod bearings should have an interval to change in the service book from day 1!

This has all been a big learning experience. Worthwhile, if a bit expensive...
 
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Caporegime
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Little ends are part of the rod and where the gudgeon pin goes to hold the piston in place.

Not to be confused with mains which are the bearings that hold the crankshaft in the block.
 

mrk

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Is that including the oil and stuff? Seems a fair price really! Check to see if they also take the clearance measurements before and after the bearing shells have been changed.
 

mrk

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I've booked my wheel refurbs for next weekend too so in a similar position. Once the engine is sorted, everything else is has been recently seen to anyway so the whole car will be in one really good state of health. Probably one of the healthiest and well documented examples on the road even!
 
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Those bearings look worryingly worn at 66k! Much worse than the ones which came out of mine at 100k (although as previously mentioned, they may not have been the originals).

What he was saying about the king race bearings has got me worried too.. Thats what I'm running in mine courtesy of Mr Vanos..

At first when he was saying the tolerance was too large I thought we might be finding out that the crank had been reground on that replacement engine.. Phew!
 

mrk

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Did Mr Vanos record the measurements? I never knew of the measurements part until Redish mentioned it. Apparently most people don't do it but I guess what he says is true, that the tolerances should be recorded because you don't want too small or too big a gap fr the oil.
 
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The mechanic in the video did state that it was still within tolerance at the larger measurement, i wouldn't be worried if they were in my car.
 
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Having never had an engine swap in my life, what happens to your old engine once your new one is in situ? Does the garage take it off your hands for a price and strip it down for parts or is it palleted up for you to take away?
 

mrk

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I still own the engine. In my case either I make a coffee table out of it, or sell it to Redish for which they can rebuild it at their own leisure and sell it on or use for R&D or another customer's car that comes in with similar problems to what mine did. They are confirming to me what the options are on that front because if they can make use of it then the final bill for this work will reflect that which is good as it saves me having to ship the engine back and find a buyer etc.
 
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Yep that's what I am thinking. So after Jan I will most likely have this sorted and a new roof motor. The two common problems sorted for years to come I would hope. Then its onto the paintwork to bring it back up to scratch.

are you getting it relocated to the boot? I'd do that.. ! I'm sure one of the guys from z4 forums would be able to get the old motor going and relocate it for a lot less than new motor which will fail again due to design flaw.
 
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are you getting it relocated to the boot? I'd do that.. ! I'm sure one of the guys from z4 forums would be able to get the old motor going and relocate it for a lot less than new motor which will fail again due to design flaw.

I will get it sorted at bmw as the warrenty should cover it. I have read that even if you get the old motor working again chances are it will fail no matter what. Which makes sense as it would have been sat in water for god knows how long. Once I get a new motor I'll decide what to do. I do now have a car cover and will be building some sort of carport next year as well so rain shouldn't be much of an issue going forwards.

Next year going forward I should also be back to looking after it again. This year I don't think I've washed it more then twice and forgot completely to check the drains. Plus I'm now parked on flat ground instead of a slope which might of had something to do with it.
 

mrk

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Update!

So a delay held the work until after Xmas. I've been given an estimate on the additional bits being done which is fine, a grand total will be given later today or tomorrow. They'd already done the new rod bearing shells and bits to the new engine while it was on the stand by new year.

As of today the new engine has been put back together and the new clutch and flywheel with supporting components all installed. The donor engine was from an SMG car so my brackets and stuff have been transplanted across, as well as the exhaust manifold.

Here's the latest video:


So all things withstanding, I should hope to collect by the weekend. Although an MOT has been booked too as that's due and I might as well get it done at the same time.

Other findings post comprehensive inspection of the undercarriage revealed a cracked rear spring, they matched the online price of £86 for Sachs which is nice. And other items like cracked undertrays, damaged aquaplane guards in front of the rear wheels, cheap stuff really so getting all of those little bits done at the same time.

They have offered £500 to keep my old engine, it's not known without a full strip down how much bottom end damage there is, and it's a 114k mileage engine too so I just said ok. Saves me having to ship it back and find a buyer.
 

mrk

mrk

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Not sure, all the ones on sale right now are fully working or low miles, so cost up to £6500. There's one selling for the £3500 mark but that includes everything. Wish that one came up when I was sourcing lol. A used 128k miles crankshaft and block with rods only is selling for £1000. Given my crankshaft is bust, should give an idea of the spares value I guess.

Another update, Redish sent a new video over:

 
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