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Quote from Comps site: " The O-Ring seals use the standard retainer and oil splash shield. The umbrella seal is normally used when a larger-than-stock diameter spring is used, in the case of a double spring, the positive-stop PTFE seal is used."

I have double valve springs installed.

When I was building the heads the guy who was instructing me mentioned this but did not push it. I figured a seal is a seal. If this is true I guess the reason I have oil on a eight plugs and a puff of smoke when car is started is because I did not do this.
 

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yeah, it's possible the plug issue is because of the seals... you could do a dry/wet compression check to determine if it is the seals/guides (top end) or if it's the cylinders/rings (lower end). if the seals are determined to be the problem an "Air Hold" tool can be used to pressurize the cylinder to hold valves closed while a spring compressor is used to remove springs on the engine to replace the valve seals...
 

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yeah, it's possible the plug issue is because of the seals... you could do a dry/wet compression check to determine if it is the seals/guides (top end) or if it's the cylinders/rings (lower end). if the seals are determined to be the problem an "Air Hold" tool can be used to pressurize the cylinder to hold valves closed while a spring compressor is used to remove springs on the engine to replace the valve seals...
^^^^^^^^^^^^^^^^^^^ what he said x10^^^^^^^^^^^^^
 

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Just make sure the piston is at TDC when you release the retainer, even with the air holding the valves shut. Done a few this way and worked well.

If using the standard orings then make sure you use the oil splash shield on top of the spring also.
 

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many hi performance retainers are not deep enough for the o-ring seal the just end up popping out

and if you use a performance valves they will not have the groove for the o-ring seal

i machine the top of the guides and use this type of viton metal clad seal and skip the o-ring

they look like this

 

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back a zillion years ago when i first started sweeping the floors in the Machine shop the Ol'Timer used to use a floating umbrella seal off of a Studebaker V8 on SBC's in conjunction with the factory GM O rings when stock springs & dampners were used as they're a tight inner diameter. i forget now the engine size, it might have been a Stude-289. i'd imagine this seal is still available and is still a viable part to use if a PC or other type positive seal isn't desired...

some applications he never used the O rings at all, just the umbrellas. it depended on if the customer bought the gasket set from us. he'd rob the gaskets and install the extra seals (O rings)


hope i helped...
 

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Speaking from experience, if you're seeing oil in the cylinders and you determined it's coming from the valves, seals alone will not solve your problem. If the guides have excessive clearance the oil will be drawn down the guides by engine vacuum. The seals may slow it down some, but it will still get there. The only way to do it right is to bronzewall the guides and ream/hone them to size. Don't let anyone talk you into knurling them, it's a waste of time and won't last. You can try putting the umbrellas or the teflon seals on, but if you know enough to notice oil on the plugs you won't be happy with the results.
 

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Speaking from experience, if you're seeing oil in the cylinders and you determined it's coming from the valves, seals alone will not solve your problem. If the guides have excessive clearance the oil will be drawn down the guides by engine vacuum. The seals may slow it down some, but it will still get there. The only way to do it right is to bronzewall the guides and ream/hone them to size. Don't let anyone talk you into knurling them, it's a waste of time and won't last. You can try putting the umbrellas or the teflon seals on, but if you know enough to notice oil on the plugs you won't be happy with the results.

+1 :yes:

also... you said it was a low mileage engine? any chance of talking to the shop about it?
 

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Discussion Starter #10
+1 :yes:

also... you said it was a low mileage engine? any chance of talking to the shop about it?
Nah had it done around '99 - '00 been sitting most of the time so never worried about the issue to much. Heck didn't put a half tank of gas through the car last year. Bad year for money. Crap room mates, I digress. Now battery is dead. Gotta get my act together. Great scenario would be a set of aftermarket heads but to many $$$.
 

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well like was previously mentioned, depending on how bad the situation is a set of seals, regardless of type, will only be masking/bandaiding the situation... but, that being said... you can try and see how it helps. a set of seals aren't too expensive, you can rent the air-hold & spring tool and do the job... but it's not necessarily the best shot for any type of longevity...

Ya Never Know... ;)
 

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If you take a spark plug and go around the crimped area with a hacksaw(the blade will stop cutting when you run into the ceramic part), you will then be able to pull the spark plug out and be left with the metal threaded part. I took this part and brazed or welded a male quick connect air fitting on to it. I did one short one and I did one with a 12" length of hose on it. Now you will have an adapter that will fit your head, very easy to do.
 

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back a zillion years ago when i first started sweeping the floors in the Machine shop the Ol'Timer used to use a floating umbrella seal off of a Studebaker V8 on SBC's in conjunction with the factory GM O rings when stock springs & dampners were used as they're a tight inner diameter. i forget now the engine size, it might have been a Stude-289. i'd imagine this seal is still available and is still a viable part to use if a PC or other type positive seal isn't desired...

some applications he never used the O rings at all, just the umbrellas. it depended on if the customer bought the gasket set from us. he'd rob the gaskets and install the extra seals (O rings)


hope i helped...
The umbrella seals I used back in the day were from a Ford 289/302. They have the same stem dia. and fit inside the stock springs with the dampner
 

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O rings can only be used on a 2 groove valve like an OEM valve. Top groove is keeper groove, lower groove is for O ring seal.
 

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think maybe just driving it would help? I mean maybe its definitely wrong and needs fixed but you said its hardly been driven. maybe it just needs to be romped on a bit?:devil::D
 
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