mvftw

What are the best valve seals for a stock '78 L82? This will be a springtime project...

page62

I decided these valve seals were the best swap I could do on my L82



"Summit"-brand Dart Iron Eagle S/S heads. Big valves, 67cc vortec-style chambers. And relatively inexpensive

isosceles

WIAI disease!!!!!

SteveG75

For stock I would go to NAPA and get some stock umbrella seals.

I ended up replacing the Crane teflons seals that my shop put on with the Edelbrock viton ones and stopped my oil burning problem. This was on my RPM heads with Crane dual valve springs.

isosceles

I used Felpro "Umbrella" seals. Got em from Autozone. Don't remember the part number.

page62

It takes one to know one!!!

Crash80

I did this a while back with the NAPA positive stop seals. They are sort of white in color and have little springs on them. These cured all of my smoky start ups. Any positive stop seal should work for you.

diablo kid

Question - to replace these seals do the heads have to come off the block?

SteveG75

Nope. Some people use compressed air or rope to keep the valves up. I just rotated each cylinder to TDC in turn (firing order) and then did the seal swap.

With the piston at TDC, there is no way that the valve could drop far enough to fall into the cylinder.

Cali,68,L-79

Crash80

If you have it done, it will run you about $400.00 or so. At least it did for me down here in TX. I don't have a compressor to do the air trick, so I had it done. I have not had a plug foul since I had the seals replaced, which was a good 8-10 months ago and my Vette is my daily driver for the most part. I took the seals to the guy that did my car and told him that I wanted to use them instead of the usual GM 'O' rings. The positive stop seals are light years better.

jacobsed

Can somebody post a picture of these positive stop seals?

Ybnormal

Here ya go, I posted a picture here www.angelfire.com/al/swhite7/temp.html


YBnormal...drive a vette

GTR1999

Will the positive stop seals fit on the guides without any modification/machining?
Gary

jacobsed

Ok, based on the picture posted, can somebody explain how they work? I pulled a chewed up set of these out of my heads and replaced them with the Felpro umbrella style. The engine has not been started yet as I've got one of those big body off restos going on.

Paul L

Here's a pic. They snap on the guide and don't move. With these, no machining was required. We put them on the 1979 L-82 last September using a compressor. Oil consumption problem solved.

jacobsed

So how do they snap onto the valve guide? Have to have a sepcial guide machined with a groove or something?

SteveG75

The valve guides should be machined and the seals just push down over them and are held in place by the spring wires. After I slid mine down the valves, I put a 1/2" deep socket over it, couple of taps with a hammer to seat it and good to go.

I originally had the Crane white teflons seals and was burning oil. My new viton seals from Edelbrock look exactly like the ones that Paul67 posted above.

jacobsed

So all valve guides have the feature needed for them to snap on already?
I don't think mine do.

GTR1999

Interesting that Paul used the Crane seals and didn't need to machine the guide? I thought the opposite,that positive seals required the guide to be machined?
The WP heads have came with the umbrella type of seal. I do have an oil usage problem that i haven't been able to track. Plugs are not fouled,some are running lean(white), no major oil leaks, but the engine uses 1 qt/600 miles. No heavy smoke unless shifting at 5500 RPM. I didn't to do a leak down or compression test yet.
Gary