[461-69bird]

Do the seals need replacing if you take the valves out of the heads or does it depend on how long they been fitted?
Also are the .530 viton ones from Butler ok to use on KRE d ports if needed?

[steve25]

If you yank a valve out of a white Teflon type seal then it needs to be replaced with a new seal, because the Kepper grove will tare up the seal on the way out.

in terms of replacement seals you need to check the tops of your guides as they could be .530", or .500".

I only use Viton type seals, no Teflon, especially if the guides are a little on the loose side as a stiff telfon seal will not follow a wabbling valve around and make a good seal.

[461-69bird]

Thanks Steve. I asked KRE and they said .530

[Half-Inch Stud]

Be sure the Guide has a chamfer because a sharp edge will snag and tear the Seal ID, causing the seal to ride up, pop-off, despite a super-tight fit when done right.

I had a tought time properly installing the Blue seals from Butler, because the guides were sharp.

[mgarblik]

FWIW, The metal jacket seals with the Viton rubber, Blue material that actually does the sealing and the little garter spring on the top are great quality. They have the advantage of a small OD as well and will fit double and triple springs without any clearance issues. They are made by US Seal/EOK. They can be purchased direct if you do allot of cylinder head work and they are CHEAP. The only snag is you have to buy a bag of 50 seals at a time minimum. But they are only about $50.00 for a bag delivered. A set of 16 from Summit or Jegs, (same seals) are about $35.00 delivered. Order direct and save a few bucks. The more you buy, the less they cost. I usually buy 200 or so at a time and that gets them down to about .60 per seal.

[Apache Warrior]

Anyone have an opinion on how 'tight' the seal should set on the guide?

I have Edelbrock 60919 heads, relatively new, and the blue Viton seals (.530) that I installed I was able to push all the way down by hand and then applied a slight blow to seat with a valve guide tool and a dead-blow hammer. They seemed to be seated well, at least IMO.

[steve25]

I have always had to used my white plastic installation tool to get seals loaded on the guides.

[cgeise]

Some people remove the little spring

[77 TRASHCAN]

Originally Posted by Half-Inch Stud

Be sure the Guide has a chamfer because a sharp edge will snag and tear the Seal ID, causing the seal to ride up, pop-off, despite a super-tight fit when done right.

I had a tought time properly installing the Blue seals from Butler, because the guides were sharp.

I have found pieces of stem seals in oil pump pickups..........wondering if mis-installed or old age...

[steve25]

I would say not just old age, but once a high mileage motor ( heads ) sit for a few months those O-ring seals are already so dry that on the next start up they just fall apart due to the expansion and contraction of the valve stem and retainer.

I recall a few times where a head gasket set was so old that when I opened up the pouch of seals they where already well into the process of drying out!

Remember that the factory used rubber O-rings, these days the ones you buy are not,