HOWTO: Valve Seals

From: Dale Olson

You probably need to replace the valve seals. It's a pain in the butt. But, if 
you have access to air compressor it can be done at home. It's not the fix to 
end all problems. First check to see if you need anything more done. 

1) run a compression check. The lowest cylinder should be with in 10% of the 
highest. Also compare your readings with stock engine specs.
2) Now run the compression test again. But, this time squirt some oil in the 
test cylinder. If the compression goes up you probably need rings. If it stays 
the same you probably need a valve job and valve seals won't fix either 

To replace the valve seals do the following:

1) Decide on which type of seal you are going to use. stock/"O"ring 

2) Get a spark plug hole adapter, air hose quick disconnect & a valve spring 
compressor tool.

3) Put the car in neutral, block the wheels & disconnect the negative bat cable

4) Remove all the plugs and valve covers

5) Remove the intake & exhaust rockers, install the valve spring compressor 
tool, squirt a bit of oil in the cylinder, bring the piston to TDC, install the 
plug adapter & hook up the air. The piston SHOULD NOT move to the bottom of the 
cylinder and you can now remove the valve spring locks (I use a magnet), valve 
spring & valve seal.

Note - If the cylinder moves to the bottom you are not at TDC. You do not want 
this to happen because if you loose air pressure and the valve does not have the
spring and locks on the valve will drop into the cylinder. 

6) Replace the seal, spring & locks. Now repeat for the other valve on that 

7) Remove the air and reinstall the rocker arms. Be sure to put them back on 
the valve you took them off of. Don't try to adjust them now, just snug them up.

8) Then repeat for the other 7 cylinders.

9) After all the seals are done. Bring number 1 to top dead center and set the 
valve lash on half the engine. Rotate the crank 360 degrees  to top dead center 
number 6 and set the other half. I don't have the exact order with me but it is 
in just about any good repair book.

10) Reinstall the plugs and valve covers (new gaskets) and your done.

  • Back to the main Monte page.