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Jimmy535i
09-28-2004, 11:56 AM
Got my cylinder head back from the shop this weekend
and installed it on the engine.

The shop repaired two cracks, installed new guides and seals and
milled the head. The shop also adjusted the valve lash.

I have pretty much have the entire project complete.

I have completed Stage One
and Stage Two of the head bolt installation with
the torque wrench and new head bolts.

So far so good. Now the minor glitch. The shop forgot
to reinstall the camshaft oiler rail on the cylinder head. I completely
overlooked this during installation also.

Next questions are:

Do I need to loosen and re-torque all 14 cylinder head bolts?
Or,
Can I get by with just removing the 4 that are needed to re-install the camshaft oiler?

Thanks for any advice.

Martin in Bellevue
09-28-2004, 12:05 PM
And, according to the e28 guys, the 2nd stage on the m30 equates to about 40 ft-lbs of torque. The final torque supposedly averages to just over 60 ft-lbs.

As a reminder, the cam & crank should be lined up pretty close before the head is placed on the block.

Jimmy535i
09-29-2004, 06:47 AM
Thank you Martin. I was pretty sure that it would be ok just to take the four bolts out. But did not want to guess without getting some other input.

I also had to order 2 new banjo bolts for the camshaft oiler. They are $5.80
each from BMA.

Jimmy535i
09-29-2004, 07:05 AM
M30 Cylinder Head Installation (New Questions)

According to Bentley Manual "Stage 3" final torque is 35 Degrees after
running engine for 25 minutes.

How perfect does this final torque need to be? I can get close with a self-
made cardboard dial and a breaker bar.

I am guessing that this is also a good time to re-check / adjust valve clearance.

When checking the "lash" is ok to check the clearance at the rocker arm and cam?
Or is it better to check it at the rocker arm and valve?

Craig
09-29-2004, 11:11 AM
Auto Zone has a dial gauge for about $10 if you have a local one. It does make the job pretty simple. I doubt a few degrees will make much difference, I have seen several posts from people that just wing it and seem to be alright.

That said, I bought the gauge because I don't want to have to do it again.

Mr Project
09-29-2004, 11:25 AM
I just used a $0.39 protractor. It would help to have a 3rd hand while doing it, but it's not too bad.

Jimmy535i
10-01-2004, 08:36 PM
Final Torque? Engine Cool or Warm.

I have my M30 all back together. Ran
motor for 25 minutes. Can final torque be done
after engine is cool. Or does motor need to be warm.

winfred
10-01-2004, 08:54 PM
i do it warm, may or may not be correct but it's worked for me


Final Torque? Engine Cool or Warm.

I have my M30 all back together. Ran
motor for 25 minutes. Can final torque be done
after engine is cool. Or does motor need to be warm.

Mr. BILL
10-01-2004, 11:51 PM
I drew a 4" circle on a piece of cardboard and marked off the correct angle and made a mark on the ratchet exrension. I had my son hold the cardboard while I turned the wrench. He'd say "stop" when I got to the correct angle.

Jimmy535i
10-02-2004, 03:27 AM
I had the same idea. Thank You All For Input.

Jimmy535i
10-02-2004, 03:34 AM
Thank you Winfred. I wanted to do it right after running it for the initial 25 minutes but ran out of time and energy. When I remove valve cover again today I will check/adjust valve lash and do final torque. It should be OK to do it cold.

Mr. BILL
10-02-2004, 08:42 AM
Great minds think alike!

Jimmy535i
10-02-2004, 04:40 PM
Project Complete - Thank You to all on this Board

I completed my first head gasket replacement and
my M30 engine has never run smoother. Thanks to all of
the great folks here that offer alot of experience, wisdom
and advice. You folks are the best.