My TR4A is making a strange (but not very loud) noise. It sounds like a
jackhammer (only much quieter) coming from somewhere forward of the driver.
You can feel it shake the shifter a little bit too small bit.
Disproved theories:
contact between exhaust and the frame.... as there is only about 1/2" clear.
After heating and prying the pipe to get 1" I had no change in the noise.
contact between the K&N airfilter and fender....removed the filter and still
got the noise.
then realized the noise only happened during a very narrow range of throttle
movement. Next theory was throttle linkage was hitting the header. I bent the
arm at the firewall about 1/8" further away from the manifold... still have
the noise.
Further investigation indicates the noise only happens when the driveline is
completely neutral. By this I mean no power applied nor any drag placed on the
driveline. It is louder and easier to reproduce at greater speeds. To repeat
simply accelerate then let off the gas slowly between power on and power off I
can sustain the sound for a few seconds by floating the throttle.
So here's the question I'd like to pose to the list.....
Has anyone ever found this and solved it. My theories are:
- U-Joint is shot and driveshaft is vibrating making the noise.
- Ditto for transmission pilot shaft, or exit shaft.
- Normal vibration for a TR4A driveline. Note: I used to have one of those
10-15# weights strapped to the rear of the unit but discarded it as "extra
weight". Was that what that darned thing was for?
The optimist says... the good news is that I got rid of enough of the other
noises to hear it. Still, Id like to fix it. Any advice or council is
appreciated.
Regards,
Rich Scotti
'66 TR4A IRS
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