Does anyone know the correct Cummins part-number for the GRAY valve-cover gaskets as per :

https://www.dieseltruckresource.com/...2&postcount=13


Thanks.

 

Last time I needed them I just went to the Local Cummins dealer and they pulled them off the shelf.

 

You must be closer to civilization than I am; down here in the sticks and bushes, if it wasn't for UPS, we would still be in the 1930s.

 

3930906 is the number I have for the gray gaskets. This is one gasket only, no o-ring for the bolt is included so you need 6 of them as well.

 

How do I determine when a valve-cover gasket needs replacing ??

I have read that they are good for several removals of the covers.


I have four engines to do this summer; that is 4 X 6 = 24 valve-cover gaskets.


My plan is to get a set of SIX and replace only the ones that need it.


Thanks.

 

When it leaks

I would just carefull inspect each one for cracks, pitting or extreme hardness. Hopefully all 4 engines don't need gaskets replacing...last ones I bought were about $9 a piece.

 

the new grey ones are good, made of good material

 

Keep a set on hand and wait until they leak OR when you have it off and they are hard and brittle then go ahead and swap before it starts leaking.

 

The black ones usually leak within a couple years. Unless they are 6 months old or newer, don't expect them to reseal after a valve adjustment.

The gray ones last and last, they will reseal as long as they are still pliable - and they stay that way a long time.