Loose Valve Seals

[ttmott]

Has anyone has this problem? If so what is the fix?
I have a pair of Edelbrock Performer RPM 454-R heads with the supplied springs on a turbocharged BBC. The cam is a Comp Grind 300BR-14 Solid roller, lift is .652 X .652 and duration is 255 X 262 @ 0.50.
The problem is the valve seals keep coming off the guides and floating up the valve stem. Looks like the problem is with all of the valves. The seals are like a PC but made of viton. Per Edelbrock the springs are good to .670; there is no coil bind. Inspection reveals plenty of clearance between the retainer and seal.
I'm wondering if the springs are dancing around and grabbing the seals or something else?????
Thanks
Tom

[Wicked Performance Boats]

I have wondered this myself, as I've seen it alot. I don't know if it's a bad manufacturing job on the seals or as you said, the coil spring walking around. I suspect that even if you have the right size spring pocket. The inner spring only has the outer spring to keep it in place. I imagine that if you could see it at 6,000 rpms, you'd be amazed at whats happening. I don't have any answers but am sure interested in this topic. As this happens too often. Budlight

[T-56]

Can you post a pic of one of the seals?
I'm assuming you both have bronze guides. In the past I've had to crimp the spring collar on a Teflon seal to get it to stay on the guide but only once on 1 guide. Are you sure you don't have 11/32" seals on 3/8" valves?
$0.02...

[Wicked Performance Boats]

Don't have bronze guides and have 11/32 seals on 11/32 guides

[ttmott]

Seals came with the head assemblies so I assume they are correct. I'm turning the motor no higher than 6300. Only about 8 hours on the heads and I've put the seals back down twice now.

[BIG TIME]

thats why a lot of performance applications dont use seals.... :mad:

[Wicked Performance Boats]

WHAT? I call BS

[steelcomp]

See, Bud...you learn something every day. :D If your valve guide to stem clearances are good, you really don't need seals on an NA motor that sees limited use, like river racing, occasional cruising, etc. Especially on the ex valve. I recommend them on the intake, though, especially if you have questionable giuide clearance. Lot of guys don't run seals at all. I didn't on my last motor. If you're running a vac pump, then it's a different story. You need to seal both valves, and use a sealer around the guide top.
ttmott...With blower app's, there's very seldom any manifold vac, so seals aren't really necessary. I'm thinking between guide clearances being a little loose, boost pressure in the intakes, and a lot of ex pressure, mixed with loose fitting seals, you're blowing the seals off. I'd just take them off and run without them. You might get a puff of smoke when you start the motor, but that's it. If you want to run the seals, you might try another seal. Competition Products sells the VTO seals, which are great. They're fluouropolymere, will stand up to anything, and come with a Hylomar sealer that you put on the guide top when you install the seal. The only other thing you can do is "thread" the tops of the guides. A lot of guides come this way already for this very reason. Problem is, you'll have to machine the guide tops down to .500 since there's nothing that'll thread a .530" dia. (Maybe metric??) After you machine the top down, you can use a 1/2"X20 die to thread with. This gives the seal something to grip.
Hope this helps.

[steelcomp]

BTW...keeping a PC type seal on the guide top is an age-old problem. It's not the spring. Last resort is you can force a .500 seal over a .530 guide, but then you'd have to wear a funny hat with two big black ears, and we'd call you "Mickey". :D

[502 JET]

Early chevy engines ran just an o-ring on the valve for a seal.There was nothing on top of the guide.

[Wicked Performance Boats]

See, Bud...you learn something every day. :D If your valve guide to stem clearances are good, you really don't need seals on an NA motor that sees limited use, like river racing, occasional cruising, etc. Especially on the ex valve. I recommend them on the intake, though, especially if you have questionable giuide clearance. Lot of guys don't run seals at all. I didn't on my last motor. If you're running a vac pump, then it's a different story. You need to seal both valves, and use a sealer around the guide top.
ttmott...With blower app's, there's very seldom any manifold vac, so seals aren't really necessary. I'm thinking between guide clearances being a little loose, boost pressure in the intakes, and a lot of ex pressure, mixed with loose fitting seals, you're blowing the seals off. I'd just take them off and run without them. You might get a puff of smoke when you start the motor, but that's it. If you want to run the seals, you might try another seal. Competition Products sells the VTO seals, which are great. They're fluouropolymere, will stand up to anything, and come with a Hylomar sealer that you put on the guide top when you install the seal. The only other thing you can do is "thread" the tops of the guides. A lot of guides come this way already for this very reason. Problem is, you'll have to machine the guide tops down to .500 since there's nothing that'll thread a .530" dia. (Maybe metric??) After you machine the top down, you can use a 1/2"X20 die to thread with. This gives the seal something to grip.
Hope this helps.
Thanks SC, I do learn something new everyday!!! now I won't have to think about JB Welding them on!! Budlight

[ttmott]

Thanks SC!
Makes sense. The Edelbrock guides have serrated grooves in them so I thought the seals would stay on better. I stuck a screwdriver between the springs and easily lifted one of the seals off.....
I'll probably use them as they are for now as I know the springs will need to be changed in the near future. The intakes are too light on the seat for the amount of boost I'm developing.
Nipomo huh? Just had a "small" piece of beef at Jocko's last week. Still passing red meat.....
Tom

[steelcomp]

Thanks SC!
Makes sense. The Edelbrock guides have serrated grooves in them so I thought the seals would stay on better. I stuck a screwdriver between the springs and easily lifted one of the seals off.....
I'll probably use them as they are for now as I know the springs will need to be changed in the near future. The intakes are too light on the seat for the amount of boost I'm developing.
Nipomo huh? Just had a "small" piece of beef at Jocko's last week. Still passing red meat.....
Tom
LOL...I don't think Jocko's can spell "small". If you're ever in the neighborhood again, please allow me to offer you an adult beverage. :D
As for the seals, just let 'em float around for now. They're no worse than the old umbrella, but keep an eye on the reataining band, or wire. If this comes detached from the seal, it can create havoc.

[steelcomp]

Thanks SC, I do learn something new everyday!!! now I won't have to think about JB Welding them on!! BudlightPat...LOL...never ending, the way you crack me up.
I'm gettin close...we're gonna have to ahve that beer soon. :D

[PC Rat]

steel,
Are these the seals you were talking about? http://www.competitionproducts.com/prodinfo.asp?number=SC531
I don't understand the sealer you were referring to.
I am using these Crane seals http://store.summitracing.com/partdetail.asp?autofilter=1&part=CRN%2D99820%2D16&N=700+115&autoview=sku
but I need new ones now anyway. Maybe I'll get the VTO from CP since they are a little cheaper.
Also, what do you recommend for valve guide clearance.
Brian

[182011]

CV pruducts Sells the corect seal to properly fix the situation a metal jacketed viton seal.