Thanks for the reply. Now the TF mystery,.
For over a year the TF has a strange problem. After redoing the head ( I had a
burned valve and wanted a lead free head) the engine would break up on long
straight runs of 4000 rpm when you increased the gas to make slight rises in
the
road. The car pulls up mountains at any rpm even 4500 for long periods without
problems. The break up only occurs on relatively straight runs with a steady
gas
pedal followed by a slight increase to make the slight hill. What happens is a
suuden loss of power and a chainy pinging noise. If you push in the clutch and
let the rpms drop to idle, then release the clutch the car recovers with full
power. The engine never dies when this happens, and if you push on( without
letting the rpms drop), the pinging continues .
I have rebuilt the carbs, changed the floats, replaced the seat and needles,
changed the plugs , points, rotor, cap, condenser, and coil.
Most believe it is fuel starvation, and I have changed fuel pumps and cleaned
all screens and filters including the tank screen.
The latest theory is timing. Although the car starts well, and runs great, the
theory is that I am near the edge of advance or retard, and the extra advance
with a hot engine at high rpm pushes the timing to the edge and I get pre
detonation. Another theory relates to the head replacement. This is that a fine
ring was left on the bores of the head when it was machined. This fine ring
heats up on steady runs of 4000 rpms and glows, thereby detonating the gas
before the spark. Aparently the machine shop should have sanded the edge of the
bores lightly after planing the head.
The whole thing is wierd . I can avoid the problem by varying the gas pedal
when
I reach the small hills, pressing down and letting up on the gas as I climb.
As
long as I don't keep a steady increase of pressure I avoid the problem, but it
is a pain to remember to do this.
I plan to redo the timing Monday and then wait for good weather to see if this
works. If it doesn't ,off comes the head. I hope I can avoid that. Taking the
head off means new gaskets and a look into the engine. I always hate to see
what other problems are lurking in there.
I would appreciate any comments.
Mike Leckstein
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