valve cover gasket
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
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- Posts: 9
- Joined: Mon Jul 16, 2012 9:11 pm
valve cover gasket
on the 0300c should I use the cork or newer neoprene gasket for the valve covers and do I need to use gasket cement? What is the tightening procedures for the valve cover, how tight?
- Bruce Fenstermacher
- Posts: 10427
- Joined: Tue Apr 23, 2002 11:24 am
Re: valve cover gasket
All C-145/0-300 regardless of the model use the same gasket. This gasket can be make out of cork, some type of impregnated paper, neoprene or silicone. It makes no difference except for personal preference.
I personally don't like the thicker silicone "Real Gasket" as over tightening will actually cause leaks as the gasket deforms. These need to be so tight but not to tight. I think using the torque specs from below will over tighten them. I know lots of people like these gaskets as they are reusable almost indefinitely. You don't want to use any cement with these in my opinion.
I like the cork or impregnated paper type gaskets. If they are fresh I wouldn't really use any sealant either instead allowing the gasket to do the work. If I was reusing or had a persistant leak I might use a good RTV high temp gasket maker very sparingly and only at the bottom of the cover where oil lies. The key to valve covers is not to over torque them. Most have been an one time and what happens is the area around the screw gets bent in toward the cylinder head and this area is drawn tight while the rest of the cover is loose and can not seal. I inspect this area and usually take a small ball peen hammer and flatten this area or using the ball side ever so slightly peen it out away from the cylinder head. This insures that the rest of the cover seals all the way around the head.
As for torque the overhaul manual doesn't have any unless I missed it. But the latest Continental SB96-7C covering torque limits does. It says - Screw-Rocker box cover. 55-65in lb or 4.6-5.4 ft lb for all models, as required. Most mechanics don't go to the trouble of dragging out the required wrenches to torque these screws instead making them just so tight but not to tight (and they sometimes mimic a torque wrench clicking sound as they do it
)
I personally don't like the thicker silicone "Real Gasket" as over tightening will actually cause leaks as the gasket deforms. These need to be so tight but not to tight. I think using the torque specs from below will over tighten them. I know lots of people like these gaskets as they are reusable almost indefinitely. You don't want to use any cement with these in my opinion.
I like the cork or impregnated paper type gaskets. If they are fresh I wouldn't really use any sealant either instead allowing the gasket to do the work. If I was reusing or had a persistant leak I might use a good RTV high temp gasket maker very sparingly and only at the bottom of the cover where oil lies. The key to valve covers is not to over torque them. Most have been an one time and what happens is the area around the screw gets bent in toward the cylinder head and this area is drawn tight while the rest of the cover is loose and can not seal. I inspect this area and usually take a small ball peen hammer and flatten this area or using the ball side ever so slightly peen it out away from the cylinder head. This insures that the rest of the cover seals all the way around the head.
As for torque the overhaul manual doesn't have any unless I missed it. But the latest Continental SB96-7C covering torque limits does. It says - Screw-Rocker box cover. 55-65in lb or 4.6-5.4 ft lb for all models, as required. Most mechanics don't go to the trouble of dragging out the required wrenches to torque these screws instead making them just so tight but not to tight (and they sometimes mimic a torque wrench clicking sound as they do it

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Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
- GAHorn
- Posts: 21308
- Joined: Fri Apr 12, 2002 8:45 pm
Re: valve cover gasket
I also switched to the Real Gaskets. Clean and dry the contact surfaces. Straighten the covers per Bruce's instructions...then, Tighten them by hand until snug...then 1/4 turn more, max. No sealant.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- 170C
- Posts: 3182
- Joined: Tue May 06, 2003 11:59 am
Re: valve cover gasket
I also switched to the Real Gaskets a number of years ago after developing leaks on several cylinders. Thankfully I have not had any more valve cover oil leaks with these gaskets. Now other oil leaks, Yes I have had and still have, but won't belabor the issue 

OLE POKEY
170C
Director:
2012-2018
170C
Director:
2012-2018
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