Valve Cover Bolts

[Jordan]

I couldn't find an answer to this in a search.  Do the 3 bolts holding down the valve cover need to be tightened to a certain torque or is tightening them so they are snug enough?  Recently oil has started to leak from two of the bolt heads and perhaps the valve cover gasket, although I don't know if that is from the bolt heads and has just run down the side.  I've loosened off the 3 bolts and ordered a new gasket for now.  There are lock washers on the bolts currectly.  Thanks for any assistance.

[awolff280sl]

fwiw, when I got a new gasket I initially under-snugged the bolts, and tightened them a little bit at a time after checking for leaks after each drive.

[ja17]

Hello Jordan,

The bolts should have copper crush washers under them. Be careful not to overtighten the bolts or you can cause other problems. Snugging them up with a short wrench should do it. Check later, you can always tighten them up a bit. Also watch to make sure the rubber gasket stays in place during installation. Check all around the valve cover with a good light to make sure it is still in place.

[jacovdw]

..Do the 3 bolts holding down the valve cover need to be tightened to a certain torque or is tightening them so they are snug enough?

Marcus,

There is a torque spec for these bolts - 5 Nm.

If you over tighten them, then the U-shaped brackets they bolt onto under the tappet cover distort. This distortion can result in the brackets rubbing against the camshaft which in turn leads to a nasty knocking sound.

[Iconic]

There is a torque spec for these bolts - 5 Nm.

Jacovdw,
I remember looking high and low for that torque spec, and I never found it.
I'm just curious. Can you tell me where you found that spec?
Thank you !

[jacovdw]

I found the torque spec in the BBB.

There are actually two values listed, namely 5 and 10 Nm.
The 5 Nm value is listed in the later data books and BBB's (found that in the 114/115 manual). The bolts used in these models are the same as those used on the pagodas btw.
The 10 Nm value is listed in the BBB for the 108 - 113 models from 1968 onwards (page 00-0/16).

I remember Alfred Esser and myself exchanging a few comments on this forum a couple of years ago about this very same topic.

I would recommend using the lower of the two values and take it from there.
If you find that you still have weeping of oil, then go to the 10 Nm value, but no higher for the reason already mentioned.

It would be worth your while to check these brackets when the valve cover is off to ensure adequate clearance from the camshaft.
I had to replace all three the brackets on my pagoda as the PO (or his ham fisted mechanic) overtightened them to the point where two fractured.
You can just imagine the racket coming from the engine...

[Iconic]

Thank you for those details.
I read all about the possibility of bending the brackets before I did my head torque and valve adjustment, so I have no issues.
I was simply curious where you found the spec because I struggled to find it ... and I don't believe I ever found it.
I'll take a look in my manual on the page you state.
Thanks again.

[66andBlue]

Here is the discussion we had about the torque values:
http://www.sl113.org/forums/index.php?topic=10218.msg67770#msg67770
It may be more important to use fresh crush washers as Joe wrote.