TFS head valve guide seals

Jack21 · #1 (**permalink**) 05-12-2002, 12:13 PM

Last question of the day...

TFS recommends using neoprene rubber valve guide seals because the valve stems need more oil than typical heads. Not sure I agree with this, or all canted valve engines would be using them.

Neoprene seals work for a few thousand miles, get hot and harden, suck oil, and after 10k - 15k miles, there's an inch of hardened crud on the underside of the intake valve.

I've always used PC oil seals with the teflon insert, and they last forever.

Felt like an idiot telling the machinist to to remove the teflon seals he'd installed, and put the rubber ones back in.

Comments? Thoughts? Experience?

Even considered polymer coating on the valve stems or guides. Oil retentive on the stem, oil rejecting on the underside. Anybody ever try this? I did put an oil retentive coating on the valvesprings for cooling when I installed them.

Double Venom · #2 (**permalink**) 05-12-2002, 02:13 PM

Big Jack,
Your over my head on this one, but I'll bet Don has an opinion on it.

DV

dscott · #3 (**permalink**) 05-13-2002, 09:15 AM

Jack, I'm not sure why they tell you to use the rubber. The aluminum heads use a bronze guide and they do require a little more oil than stock but almost every head I buy uses the teflon seal. You are right about the rubber, it doesn't last. I've only used the TFS heads once but I can't think of any reason why they would be different than everyone else. I've never tried a coating on the valves so I can't comment.
Don

Jack21 · #4 (**permalink**) 05-13-2002, 06:56 PM

Thanks Don. Figured another engine builder might have an opinion on this. I think TFS uses bronze guides on their race heads, but the ones I have use cast iron guides.

I aquiesced to the rubber guides until I could get some in-service comments on this.

TFS had taken their heads off the market for awhile when I was shopping for heads, '97 - '98 due to abnormal valve guide wear. I got one of the first of their redesigned sets.

It's now 4 years later, TFS heads are popular, so I thought I'd see what their service record has been for valve guide wear. Otherwise, when the engine has 10 - 15k on it, it gets teflon seals.