Not sure what stem to guide clearance was but the head was done at a decent shop in the area and when I got it back and inspected it all looked and felt good. There are stem seals on the intakes. There are stainless valves in this head if that could make a difference as far as expansion or whatever. But you would think if that were the case it would be similar for all cylinders.
Is it possible that number six oil rings could be stuck in the grooves?
P.J.
--Previous Message--
: Well the higher compression in #6 is
: consistent with a cylinder getting
: oiled, similar to a "wet"
: compression test.
: Assuming that it is oil smoke, and
: there isn't heavy crankcase pressure,
: inlet guide/seal and oil rings are the
: two primary suspects.
: If it's going by the guide, it will
: suck it in under closed throttle ie
: downshift decell, rings will smoke
: heavy on acceleration.
: If it's going down the valve
: stem/guide, and it's real bad, the
: underhead of the valve will actually be
: wet with oil, you can see it.
: The progression of fouling towards the
: rear does suggest the possibility of it
: getting down from the head, due to the
: design of the oiling system, a lot more
: oil is in the rear of the rocker box.
: Do you know what the stem/guide
: clearances are, and if there are seals
: on the inlet valves?
: Glen
:
:
: --Previous Message--
: Hi.
: I did some testing tonight and here is
: what I found.
: Compression. 150,150,160,160,160,175
: Plugs were white grey(1-2)
: Black sooty(3-5}
: Black oil fouled(6)
: I also checked fuel pressure at about
: 2-3 Lbs. Don't have a really good guage
: but the point was to make sure the fuel
: pressure was not overpowering the carb.
: floats and it was not.
: I swapped out spark plugs with a clean
: set and ran the engine for a few
: minutes up and down RPM range. Checked
: plugs again and exact same results.
: Number Six cylinder obviously has some
: issues.. Now what??
: P.J.
: --Previous Message--
: O.K. I might be starting to think
: about a fix now.... Is there any way to
: know if the oil rings are shot or maybe
: a better way to put it would be: Can
: the oil rings be bad and compression
: rings be O.K.?
:
: Yes oil rings can cause problems if
: they are incorrectly fitted or damaged
: in some way.
: Obviously it won't show up on a
: leakdown or compression test though.
: BTW, if you suspect a fuel related
: issue, you can actually smell the fuel
: in the oil and the drain oil will be
: very thin. As it gets worse you will
: also see a drop in oil pressure.
: Glen
:
:
: --Previous Message--
:
:
: --Previous Message--
: Yes as Doug mentioned, it could very
: well
: be a fuel issue.
: If it's running too rich, you will get
: the obvious (darker colored) smoke, but
: it will also wash down the cylinders,
: dilute the oil, and start burning oil.
: Long term results are heavy cylinder
: bore and top ring/groove wear.
:
: Remember... a problem is just the
: beginning of a solution...
: Keep us posted,
: Glen
:
: --Previous Message--
: Hi.
: I don't see any oil fouling on the
: plugs but they are black and soot
: covered. I have not done any tests yet.
: I did do one very smokey burnout, said
: some very choice words and parked the
: little bugger in the garage. I keep
: hoping it's a fuel problem like the
: webers are way too rich but I switched
: to the leanest set of main jets I have
: and it was no better. Maybe when the
: weather breaks I'll get some testing
: done or maybe I'll give Craigs list a
: try.
: P.J.
:
: --Previous Message--
: Just a couple thoughts, keeping in mind
: the fact that the problem exists with 2
: different engines...
: An external top-oiler without a
: restrictor will fill the rocker box and
: let oil down the intake guides, but
: this will smoke worst under closed
: throttle.
: Crankcase venting properly?
: Have you done (dry)compression test and
: leakdown test?
: Are any of the plugs getting oil-fouled
: yet?
:
: Old Corvette??? Geez, that's what go
: tme into sports cars, After I trashed
: my '61 (in '71), my Dad OK'd my getting
: my first TR (4), he figured I couldn't
: get in as much trouble with a little
: 4-cylinder...
: Glen
:
:
: --Previous Message--
: Hi again.
: Here we go again. I've been driving
: the GT6 a bit this summer and it's been
: running great. I absolutely love the
: Toyota T 50 trans. Shifts crisp and
: smooth. Gear ratios are perfect for the
: street. My only concern was with the
: fact that I removed the AL.flywheel and
: it really hurt performance.. HOWEVER:
: Last week I noticed the exhaust was
: starting to become noticeable. Light at
: first but getting worse. Definitely
: blue. Spark plugs are black and sooty.
: At first it was only smoking when you
: take off from a stop. Now it smokes all
: the time and when you take off from a
: stop it's a fogger. Obviously time for
: some intervention. This engine only has
: a couple thousand miles on it and I
: don't think I can make myself tear it
: down again. At least not now. Can
: anyone give me a reason WHY this thing
: is going through piston rings? Two
: years ago I tore the engine apart twice
: because I couldn't get it to stop
: smoking. Reringed it twice and finally
: gave up and rebuilt a whole different
: engine. New pistons and rings. Bored
: .030 over. New cam and cam bearings.
: New everything within reason. Freshly
: rebuilt head with seals. New valves.
: How can this be happening again???
: Might have to give up and buy an old
: Corvette soon.
: P.J.
:
:
:
:
:
:
:
: Hi.
: O.K. I might be starting to think
: about a fix now.... Is there any way to
: know if the oil rings are shot or maybe
: a better way to put it would be: Can
: the oil rings be bad and compression
: rings be O.K.?
:
:
:
:
:
:
:
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