Brian Sanborn wrote:
>
> >that's right but Ted Schumacher recommends fitment of small block Chevy V-8
> >valve seals if you're having the head redone.
>
> Andy,
>
> I second the motion... my TR4 engine has teflon valve seals on the intake
>valves. I had it done along with hardened valve seats when the head was done.
> Modern technology is a good thing.... especially if it does not show.
>
> My shop took the standard bronze guides and machined them to accept teflon
>seals that they supplied to fit.
Not to make light of anything Ted Schumacher says, but this probably
needs further clarification. For most Triumphs, cast-iron guides are
standard, not bronze. If an early engine has them, they were likely
installed as part of a prior rebuild.
It might not be a good idea to install stem seals on the cast iron
guides, since both the guide and valve are steel, and very likely need
more lubrication, hence no stem seals in the first place. Some of the
worst-worn cast-iron guides I've ever seen were on engines with stem
seals (earlier Ford V-8s with umbrella seals were notorious for that,
especially as the engine got older and oil pressure dropped).
Bronze guides, however do well with less lubrication, which is why most
aluminum heads have aluminum bronze guides (cooperative expansion rates
is another reason) and so valve stem seals are a stock item for them.
And, yes, the replacement bronze guides do need to have a groove cut in
them since the most commonly available stem seal for that diameter guide
snaps into place on the guide.
As for Kyle's original question about the stem seal interfering with the
inner spring, that likely means that the stem seal chosen by the machine
shop is inappropriate. If there are cast iron guides still installed,
tell them not to put any on. If bronze guides are installed, they must
machine grooves in the guides to accept a stem seal which will fit.
Don't let them just press them on, because they will come off and
eventually get beat up between the spring retainer and the guide.
Cheers.
--
Michael D. Porter
Roswell, NM
mailto: mporter@zianet.com
`70 GT6+ (being refurbished, slowly)
`71 GT6 Mk. III (organ donor)
`72 GT6 Mk. III (daily driver)
`64 TR4 (awaiting intensive care)
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