Well, it is with a heavy heart that I ask the following question. I'm
concerned I know the answer before I hear it. I'm just hoping I'm wrong.
While I am curious what the problem could be, based on everyone's
experience, I am really looking for how to best eliminate different
components as being the issue. Any suggestions as to how to proceed, and in
what order? As always, I am most appreciative for your logical thinking
skills.
PROBLEM: It developed this weekend while driving. When driving the TR6
(approx 70K miles), there is a noticeable knocking (rat tat tat tat tat
....) that begins almost exactly at 2500 rpm. I seem to hear it most
pronounced in the passenger foot well (but this could be compounded by the
fact that the carpet is out of the car, and there is a 2 inch gap in the
transmission tunnel cover where it is supposed to meet the bulkhead). While
I can hear it when I quickly rev the engine above 2500 rpm, it is nowhere
near as pronounced.
POSSIBILITIES: I have thought about bad engine bearings, extreme valve
noise, timing chain, oil pump, and just plain new rattles.
PROBLEM WITH DIAGNOSIS: Other than never having dealt with a sound like
this, when the bonnet is open, I cannot seem to discern where the problem
is, and obviously cannot pinpoint the sound when I'm driving.
SOME OTHER INFO THAT MAY BE PERTINENT:
1) Car had sat for 5 or more years without running - until beginning of May,
1999. Oil has been changed several times since starting it up in May.
2) In 90 degree weather, oil pressure tends to idle around the mid-point
between 25 lbs and 0 lbs on the gauge, and at driving rpms, oil pressure
tends to hover around 25 lbs. I use 20W-50.
3) I have not opened the engine yet. I've been hoping I could get another
25K miles on it before a rebuild.
4) I have not yet done a compression check. I'm thinking this might be a
good idea, but am afraid to drive the car for the 10 minutes prior to
compression testing to warm the car up.
If I have left anything out, or need to be more specific, please write to me
off list, and I can post the new information to the list for all to see.
Thanks to all who read this,
Eric Conrad
Denver, CO
econrad@teal.csn.net
1976 TR6 CF52678U
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