Sorry for the band width, but several people expressed interest in my
findings, so I'm posting them to the list.
For those just tuning in . . . I had a head completely rebuilt for my TR-4
and discovered that there was a lot of oil getting into the combustion
chambers. The old head looked normal, and the engine was recently completely
rebuilt, so I doubt there is any problem on the lower side.
At the same time I put the new head on, I also installed a stainless steel
braided, external rocker oil feed pipe. I know that this pipe puts out a
whole lot of oil to the rocker assembly (oil guyesers under the valve cover)
because I made a terrible mess when I was adjusting the valves. Turned on
the engine with the cover off, and instantly . . . . .oil everywhere!
I, and apparantly at least one other person on the list, think that the early
TR valve guides (which do not have seals by the way) simply cannot handle
this amount of oil, and thus a good bit gets into the combustion chambers.
It tries to burn, and accumulates and fouls the plugs and leaves a real
mess.
I took the head back to the shop, and the guy (well respected) checked it out
and said the valves and guides fit just fine. He guaranteed they weren't
lose.
I looked real close, and there is only one other possibility in my mind. The
valve guides installed were not solid bronze pieces with holes drilled in the
middle. Rather they looked like iron cylinders with thin bronze sleeve
inserted in the middle. This bronze appears to have a "gap" running down
it's length, much like piston rings have a gap. It is small, but I can see
it.
My theory is that the valve guides do indeed fit properly, but that were
meant to have an oil seal at the top of them. Even though the "gap" is tiny,
I think it is enough to suck oil down into the chambers. This effect is only
heighted by the tremendous amounts of oil produced by the external feed pipe.
When I put the sucker back together, I'm going to leave off the external oil
feed line. My engine is recently rebuilt, and the block was boiled out, so
it shouldn't have any problem getting sufficient oil to the rockers.
I'll let you know how it goes, and in the mean time, I might mess with making
a "performance" cylinder head. This time I will install guides such as the
ones Moss sells (which I believe are solid silicone bronze cylinders) Then I
suppose I can try the oil feed pipe again and see what happens, but this is
likely to be a little while in the future.
Scott Tilton
In Richmond VA
Returning you to your normal programing (bad pun . . . . I know)
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