I have a package of MP Viton Valve Seals I bought in 2001 for the 440 in my '71 Charger.

A few months later, I bought Edelbrock Heads, so these sat in the original package since.



QUESTION: Which seal is for intake and which is for exhaust (Tall-Cup versus short umbrella-seals, look like black contact-lenses?) Guessing the taller-cups are for Intake, but not sure.

The reason I suddenly need to know, I decided to try using these on the AMC V8 in my Jeep CJ-5.

The AMC cylinder heads received a complete valve-job, new seals, springs, retainers, keepers a year earlier, so was surprised to have oil-burning issue. Note: Compression for all 8-cylinders was within specs, so valve-seals or perhaps (less likely) worn guides suspected.

In any event, I decided to replace them. The taller Cup-Type Mopar Perf Viton Seals look similar to the Intake AND Exhaust seals on the AMC motor (AMC uses "the same" tall-cup-seal on both intake & exhaust.)

So, today I used up two of the taller cup seals on my #7 cylinder valve guides, as that cylinder was oil-fouling the sparkplug.

The AMC seals I removed looked fine (almost like New) so I wonder if they just came loose off the top of the valve-guides?

In any event, the exhaust is now "clean" on that right-side bank of cylinders. (Note: dual exhaust, no crossover.)

But, now I notice that the Left bank is smoking a bit too, though WAYYYY, WAYYYY, WAYYYY less than the right bank with he fouled plug had been. Probably didn't notice the slight/tiny amount of white smoke from the Left bank, due to the choking amount from the right bank before I fixed it.

Am considering using the rest of the seal package to do all the cylinders in the left bank. Should that work/be Ok?

Also, weird question... Could these seals, seal TOO well, and starve the guides of all lubrication? The guide diameter of the MP seals is a perfect fit, however, the end that fits over the valve guide is "snugger" than the old (Fel-Pro) AMC seals I removed.

When I say "snugger," the MP seals feels/seems like a more precise and better fit than the AMC/Fel-Pro seals I removed.

Thanks.

Those tall ones are for the intake, short umbrella type are exhaust. The reason the new ones are tighter is the guides. They may be flexible, but that doesnt mean the AMC ones were good. Just not dried out. When the seals hold on to the guide, the valve has to move properly or they will either pop off over time, or the center hole for the valve stem will distort. In either case, the seal becomes less effective. If you had the heads completely done properly, the guides would have had to be done. At least in 95% of all used heads I bring in do. Because the good cutting equipment can't work well with marginal guides. If you didnt have guide work done, the shop's equipment isnt that great, and they will have oil use issues again in the short term.

Appreciate the reply/info.

The shop that did the work has a decent reputation, though not high-end performance. This was just a fairly common job for them.

So far as I know, they didn't replace any valve-guides, but did clean/inspect and may have knurled any guides that needed attention.

Thanks Again.