Torque for M42 rocker cover bolts?

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kevin316i
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Post Fri Feb 03, 2006 11:09 pm

Can anyone tell me what the correct torque is for the bolts on the rocker cover for the M42 engine. I have read somewhere it is 10Nm, but want to check to make sure.

Would the torque values for the bolts on the sump be the same?

Any of the torque wrenches I have looked at start at 10Nm, so I want to be sure before buying.


Thanks,
Kevin.
ian332isport
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Post Sat Feb 04, 2006 2:19 am

Hi Kevin,

Yes, 10Nm is correct for the rocker cover bolts.

BMW lists two different settings for the sump bolts depending on what grade they are. Regular 8.8 grade are 10Nm, but they also list a 10.9 grade which is done up to 12Nm.

I got a nice little Britool Torque wrench for these low settings. It runs from 3Nm to about 30Nm I believe.

Cheers,

Ian.
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WerkdE30
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Post Sat Feb 04, 2006 2:35 am

if u think u need a torque wrench to do up rocker cover n sump bolts your not someone who should be takin either of these things off (especially the sump thats a prick of a job) ...

but if your determined to, go and get a 10 mm T-bar u cant go wrong unless your built like Arny... or a quarter driver ratchet n only use 2 fingers. Oh and dont forget to put some sealant on the half moon seals when u put the new rocker cover gasket on
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Kos
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Post Sat Feb 04, 2006 2:39 am

every nut and bolt has a torque setting, and its nice to do a "correct" job on a car. even if it seems a bit OTT i say fair play to them.
ian332isport
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Post Sat Feb 04, 2006 2:40 am

WerkdE30 wrote:if u think u need a torque wrench to do up rocker cover n sump bolts your not someone who should be takin either of these things off (especially the sump thats a prick of a job) ...

but if your determined to, go and get a 10 mm T-bar u cant go wrong unless your built like Arny... or a quarter driver ratchet n only use 2 fingers. Oh and dont forget to put some sealant on the half moon seals when u put the new rocker cover gasket on
I agree to a point, but 10Nm is naff all, and very easy to exceed.

I'm not sure what it's like on the M42, but stripped threads are extremely common on the S50 engines (on the cam cover). I had to fit approx 20 Helicoils on my engine, and that had only ever been dealer serviced :roll:

Ian.
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WerkdE30
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Post Sat Feb 04, 2006 2:53 am

yes i agree and i have seen countless ones stripped out and im all for doin a correct job. Sorry i didnt mean to be harsh i just have high standards as my arm doubles as a torque wrench.

i just think the money will be a waste once you get a feel for it (and they aint cheap for a decent one) if u find one or two stripped out it wont hurt to just put some silastic on the thread but of coarse helicoils are the best option

"and that had only ever been dealer serviced"

honestly i recomend u stay away from dealer service as they are gettin paid on an award bonus scheme and will do a rushed job a lot of the time your new rocker cover gasket ends up in the mechanics personal supply or the bin. small bmw specialists take the time and care your bmw deserves (usually) and will save you mega $$$$$$$$$
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kevin316i
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Post Sat Feb 04, 2006 4:05 pm

Thanks for the feedback guys.

Werkde30,
I'm going to try not taking offence to your comments. You seem to infer that I'm not up to doing the job if I need a torque wrench.

I want to do the job properly, and every bolt has a defined torque, so I want to know for sure what these bolts should be tightened to, and not end up stripping threads. There is a small oil leak around the rocker cover and sump, so I want to check the bolts aren't loose. If this doesn't work, then its time to replace the relevant gaskets.