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soorooshg

Need Help...Broken M5

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16 hours ago, kobayashi said:

Have you checked the coil, distributor cap, rotor and leads? If they are original they could very well be the problem and I’d replace them anyway at that mileage. 

Yeah they’ve checked all of that and they said they’re fairly new, the whole lot, so it can’t be that

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Quick update:

 

Got a call this morning, they took the valve cover off and it turns out the inlet camshaft has skipped 2 teeth and it’s obviously mistimed. He said the camshaft itself is slightly damaged but he didn’t say it definitely needs replacing. He also mentioned that it couldn’t be a bad tensioner as apparently on S engines that’s not a common fault or something? So that’s what we know so far, he’s got to dig deeper now. At least we’ve got some progress but I’m praying it’s not going to be a huge job and more importantly a huge bill. 

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Also another thing worth mentioning is that the car (3.6) has had 3.8 cam gears installed along with a chip. Now is this anything to do with the cams being mistimed? Does anyone have any info or stories of this happening as I can't really find much info on it online. What are the differences between the 3.6 and 3.8 parts, in terms of size, number of teeth etc. Bear in mind, this is something that was done quite a few years ago, and the problem has only arisen now, maybe 20-30k miles after. 

 

Quite a few people are pointing me towards a failed tensioner as apparently the unit in the S38 is highly complex and different from a regular tensioner. 

 

Appreciate all the help everyone 

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the 3.6 MAF is also used on the 968 porka, e34 alpina bi turbo and certain audi quattros.  The guy in cambridge is a well know repairer of them in porsche world.  3.8 MAFs are back online, BMW will send it to bosch for a rebuild and its 500 euro at the minute 

 

The 3.8 cams were fitted by Phil crouch to your car, its the pink floyd car isnt it?

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18 hours ago, Bumbaclut said:

the 3.6 MAF is also used on the 968 porka, e34 alpina bi turbo and certain audi quattros.  The guy in cambridge is a well know repairer of them in porsche world.  3.8 MAFs are back online, BMW will send it to bosch for a rebuild and its 500 euro at the minute 

 

The 3.8 cams were fitted by Phil crouch to your car, its the pink floyd car isnt it?

Yeah we figured out it was the same guy (JDSPorsche) who reconditioned the MAF a few years ago. 

 

Yes it’s the same car, been told by Andy that major work was done by CPC Performance Engineering apparently a chap called Phil Crouch knows my car inside out 

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Had an m635 which jumped 2 teeth on the crank (similar engine to you) - so both inlet and exhaust cam were 2 teeth out.  Didn't cause any cam or piston damage, but they were 264 cams which will be different to yours.   Cam chain was absolutely knackered with 2 rollers actually missing (found them in the sump).   I got my cam sprockets slotted and fitted schrick 272's and timed them precisely myself.  Hope your cam isn't too damaged.  I would inspect the chain very carefully and fit a new tensioner as a minimum.  Then get the cam sprockets slotted and time precisely.   £90 to slot my sprockets with 6 deg adjustment either way.

 

Edited by M635uk

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On 8/20/2018 at 12:52 PM, soorooshg said:

Yeah we figured out it was the same guy (JDSPorsche) who reconditioned the MAF a few years ago. 

 

Yes it’s the same car, been told by Andy that major work was done by CPC Performance Engineering apparently a chap called Phil Crouch knows my car inside out 

Phil is well regarded, he rebuilt my e36 M3 evo engine when it dropped a plug 2 weeks after i bought it so i share your pain.

 

That car fought me all the way but was lovely in the end.

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Small update 

 

turns out the camshaft fiasco wasn’t the cause of it, they re-timed the engine and put it back together (checking that nothing needs replacing) and that still didn’t solve anything. Mechanic called me today to say they’re now looking at the bottom end, and that there’s something wrong with the crank pulley. He did explain but the line was so bad plus he spoke so fast I hardly understood. Something about the teeth not being right and about the bolt that attaches it to the hub is sheared or something? Might be wrong but basically they’re looking at the crankshaft area now. Almost 3 weeks it’s been now. 

 

Edit:

 

im pretty sure he’s talking about this part

 

https://www.realoem.com/bmw/enUS/showparts?id=HD92-EUR-09-1990-E34-BMW-M5_36&diagId=11_0332

Edited by soorooshg

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Crank hub failure then.   Nut and/or woodruff key?  Link below shows photo's of what may have happened.   I would not recommend his solution though - JB welding the woodruff key in place!   But hope it helps you progress the diagnosis.

 

http://www.firstfives.org/faq/keyway/Crank_Keyway_Repair.html

Edited by M635uk

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On 8/22/2018 at 4:34 AM, M635uk said:

Crank hub failure then.   Nut and/or woodruff key?  Link below shows photo's of what may have happened.   I would not recommend his solution though - JB welding the woodruff key in place!   But hope it helps you progress the diagnosis.

 

http://www.firstfives.org/faq/keyway/Crank_Keyway_Repair.html

Yep that’s exactly what it seems to be. He showed me it all yesterday and he’s fairly certain it’s that. However getting to it is a long process apparently you have to take the sump off along with the timing cover of course. Any idea how much the replacement is? He said it’s either that, or the crankshaft itself is fucked, which if so, it’s gonna be an engine out job which I will be absolutely furious if it is. Also the end of one of the camshafts has a little crack in it but he said it should be fine. 

Edited by soorooshg

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On 8/21/2018 at 10:25 PM, cableguy said:

Have you thought about shipping it over to CPC as they sound like the kiddies when it comes to these cars...?

 

C.

I can’t really do that as it’s been with these guys for a few weeks and to be fair they do know what they’re doing, just the fault happened to be at the bottom of the list of what was expected that’s why it took so long to diagnose. 

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23 minutes ago, soorooshg said:

Also the end of one of the camshafts has a little crack in it but he said it should be fine

 

Would you really want to take the risk while the engine is being stripped...?

 

C.

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1 hour ago, soorooshg said:

Yep that’s exactly what it seems to be. He showed me it all yesterday and he’s fairly certain it’s that. However getting to it is a long process apparently you have to take the sump off along with the timing cover of course. Any idea how much the replacement is? He said it’s either that, or the crankshaft itself is fucked, which if so, it’s gonna be an engine out job which I will be absolutely furious if it is. Also the end of one of the camshafts has a little crack in it but he said it should be fine. 

I would do a search as Frank Farhey Motorsport in the US did an upgraded damper which illuminated this issue.   Re the crank been knackered - that depends if there is any damage to the nose.    Yep the sump comes off, if the damper bolt is sheared then the damper should come off no problem!  then you will be left with extracting the bolt shank, which should come out as the torque has gone from the damper failure.

To get the crank sprocket off you need a really really good puller.  The sprocket is heat shrinked on to the crank nose so it will be tight on there.  I would replace the crank sprocket as a matter of course.  Hopefully the crank isn't actually damaged.

I did a full chain, guide and sprocket change out on my M635 with the engine in the car.   So maybe the engine doesn't have to come out.  Depends how far you have to dig and what damage you find.   Getting the sump off to inspect things is straight forward.  Realoem.com quote the damper at $660 but best to ring BM for the actual £ cost.

 

https://www.realoem.com/bmw/enUS/showparts?id=HD92-EUR-03-1990-E34-BMW-M5_36&diagId=11_0332

 

You can get a guide on prices for the other bits from their too.

 

Edited by M635uk
link added

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58 minutes ago, cableguy said:

 

Would you really want to take the risk while the engine is being stripped...?

 

C.

Yeah that’s very true but this job has already cost me £1500 and we haven’t even got to the actual problem yet, god knows what it’ll be at the end, probably £2500 no doubt. Another camshaft I’m guessing will be at least £1000? Is there any way it could be repaired? As it’s literally right on the end. Very very frustrating to spend so much money on a car that I was told has no issues and will run like clockwork for it not to even get me home, and facing a bill of almost £3000 and I’ve basically not even driven it yet! I feel conned if I’m honest. 

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9 minutes ago, soorooshg said:

Yeah that’s very true but this job has already cost me £1500 and we haven’t even got to the actual problem yet, god knows what it’ll be at the end, probably £2500 no doubt. Another camshaft I’m guessing will be at least £1000? Is there any way it could be repaired? As it’s literally right on the end. Very very frustrating to spend so much money on a car that I was told has no issues and will run like clockwork for it not to even get me home, and facing a bill of almost £3000 and I’ve basically not even driven it yet! I feel conned if I’m honest. 

Feel for you, terrible bad luck. 

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I share your pain but does this type of failure have any symptoms or do they just fail? 

 

If not its just rotten luck like my m3. Even more annoying for me is I had new plugs in the boot ready to fit. 

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Sooroosh, e34 M5's can be expensive cars to run if you're relying on specialists.

 

IMO it's better to bite the bullet now and get everything sorted engine wise, particularly if it's a daily.

 

C.

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In my defence, neither myself or the owner before me experienced any running issues.

I'm not sure I could know a bolt/shaft was about to shear off and it just seems extreme bad luck it happened on your way home after purchasing the car.

 

If it's any consolation, I had very recently spent 3k on complete ac recommissioning on this car, even as it initially appeared 'only' the compressor had to be bolted on.

I guess that's 3K less YOU have to spend (!) but as other people have mentioned, M5's are not cheap cars to run.

 

I do feel bad for you but with no prior knowledge of any issue, I can only hope it can be fixed quickly for you to enjoy as it was intended. 

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To be fair this car has covered, high milege, its been clocked and its had a few owners who havent looked after it before any of these forum guys bought it.    

 

Might sound harsh but if you want a mans car,  you have to pay the mans bills. M5's get more expensive to run the older they get 

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Agreed. I firmly believe this car was sold to you in good faith and I don't for one minute think you have been "conned". IMHO you just got unlucky and this can happen to any second hand car you buy regardless of price or condition. You must bear in mind that this is a high performance car that is now getting on for 27 years old and shit is going to fail without warning, fact. Take it on the chin, get it fixed and enjoy :) 

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The M5 is a wonderful machine ... But most have seen the rev limiter at some point .... sadly falling into the wrong hands during the 3k days.

  I have no doubt the former owner saved this M5 from being scrapped with money and love.

I feel for you're rotten luck and hope the final cost is not that bad ... 

   

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