Re: [ihc] Flattening valve covers?

[Steven Stegmann <steve.stegmann@xxxxxxxxxxxxx>]

Here's how to do the valley cover gasket.
 
The valley cover is not the right shape after you bolt it down.  Poor design of this piece.  The bottom of the valley draws up over 1/16 inch as you torque the bolts.  More like 1/8 inch on mine.  Here's what I did and the engine is bone dry for a couple years now.  After you have done a preliminary cleaning on the surfaces, bolt the cover in place with no gaskets and no sealer.  Can you see between the cover and the block at the front and the rear?  Does the same thing with gaskets in place and causes leaks.  The covers aren't designed correctly.
 
Steps to install the cover.
 
1. Std lecture on cleaning the gasket surface.  But do it twice & use solvent to be sure the Permatex Red can really bond to the metal.
 
2. Only use gaskets (which you will make) on the front and rear edges of the valley opening.  Do ***not*** use any gasket material along the cylinder heads.  The cover will not fit properly when you just set the cover in place with these gaskets front and rear.  It will ride on the front and rear gaskets and the sides along the cylinder heads will not touch on both sides at the same time.  Looks awful and is really messy with Permatex Red everywhere (did I mention not to use anything but Permatex Red?  Especially not Permatex Blue).
 
3. Put Permatex Red (Do not use Blue!!!!!!) on all sealing surfaces and both sides of the gaskets (plural, which you will make) and rub it around with your finger to be sure it has "wet" the surfaces.  It will need to be about 1/16 inch thick after this.
 
4.Put the cover in place, start the bolts and torque the gasket cover bolts to 10 ft-lbs immediately, and do **not** go back and retorque later, this *will* cause leaks.  Don't think about what it looks like before you torque the bolts.  After torqueing the bolts it should be fitting very nice.
 
5. Leave it set 24 hours before starting the engine.  You need to let this stuff cure if you're serious about no leaks.
 
Now to the fun part.  Buy some gasket material.  The best kind is the composite sheets made of a mixture of rubber and cork.  Straight cork probably won't work.  This needs to be high quality because of the way you will be cutting it.   You'll need to get sheet stock not just try to use valve cover gaskets.  Get it 1/8 inch thick, that didn't seem to be a big deal.  You're local auto parts may have to order this stuff but they can get it if they are competent.
 
First make a paper pattern of the part of the valley cover sealing surface that runs from the left cyl head to the right cyl head, both the front of the engine and the rear of the engine.  
 
Next, cut the gaskets out of the sheet using these patterns.  You're halfway done with the gaskets.
 
Next you'll need to thin the edges of the gaskets.  The gaskets should be left full thickness in the area running along the bottom of the valley.  The sides, where the gasket climbs up to meet the cylinder head (seems like 3 inches on each side from memory) needs to be tapered in thickness.  It should be full thickness at the bottom and tapered to paper thin right where the gasket meets the cyl head.
 
My guess is that you'll ruin at least one gasket doing this.  I sure did.  I tried a bunch of things to thin the gasket and settled on new single edge razor blades just held in my hand.  This thinning is a tedious business and don't shave off your finger prints,  that would hurt.
 
You now have two wierd looking gaskets, one front and one rear.  It is a ticklish job to get them to stay in place till the cover is tightened but if you get the thickness skived evenly they will work.
 
Steve

"Allan W." <allanw@domain.elided> wrote:
> -----Original Message-----
> From: owner-ihc@domain.elided [mailto:owner-ihc@domain.elided]On Behalf Of
> John Hofstetter
> Sent: Tuesday, April 27, 2004 7:10 PM
> To: spamaddy@domain.elided
> Cc: ihc@domain.elided
> Subject: Re: [ihc] head gasket advice?
>

> Sealing the rear of the valley plate is the hardest seal to make leak
> proof. Valve covers should be flattened before putting them on.

So John, I ran over a set of valve covers repeatedly in the
street. They are very flat now. I'm having trouble seeing
how these are going to fit on my engine now, and how this
will prevent them from leaking. ;-)

Allan W.
waiting for enlightenment