copper exh manifold gskt

[richard key]

I started installing copper exhaust manifold gaskets on the 455 yesterday =
and quickly realized that I didn't know which direction the gasket should =
face. I need to know whether the raised part of the indent in the gasket =
ought to face the head or the manifold. Maybe it doesn't make any =
difference but I'm not sure and there was no information printed on the =
packaging.

Thanks in advance for your help. This list is a terrific resource.......I =
don't have a GMC (yet) but much of the information here applies equally to =
my Revcon which uses the same engine/drivetrain.

Dick Key
76 Revcon=20

 

[dave lowry]

>In a message dated 8/14/2000 9:30:23 AM Central Daylight Time,

>
>to face the head or the manifold. Maybe it doesn't make any difference but
>I'm not sure and there was no information printed on the packaging. >>
>
>I'd put the smooth side against the head (IIRC FelPro says put the metal
>(raised) side against the manifold).
>Mississipi version only - I'm sure New York will differ - shit storm on the
>horizon:>)
>
>Lanier

Yer BAD!

Dave (advisor/navigator) & Dege (ALL else), '76 Royale, Santa Barbara, CA

 

[philip l. stewart]

> I started installing copper exhaust manifold gaskets on the 455 yesterday and quickly realized that I didn't know which direction the gasket should face. I need to know whether the raised part of the indent in the gasket ought to face the head or the manifold.

Dick,
I installed the copper gaskets with the raised ridge facing out towards the manifolds. I sealed both sides with Permatex Utra Copper High Temperature RTV (I believe it was Permatex) and torqued the bolts to 25 ft-lbs. I think the sequence is important. Start with the two middle bolts and sequentially tighten them with the outside bolts coming next. Save the middle
upper bolt for tightening last. I check the torque on the bolts every oil change and so far I have been leak free for over 8,000 miles. I did get the manifolds surfaced flat before installing the gaskets. HTH
Phil Stewart
'76 Transmode, TN