Not a direct answer to your question, but I wanted to relate a nightmare I
dealt with when rebuilding my TR6 years ago... I reinstalled the engine and
bolted on all the peripherals, set timing, basic adjustment on carbs, etc.
Started it up - idled OK, no strange noises, oil pressure great. But when I
took it out on the road, it was extremely anemic, to the point that it was
unusable. That's where the nightmare began. I tried everything I could
think of, re-rebuilt the carbs, even bought and rebuilt a second set of
carbs out of desperation. Changed to a high performance coil - checked and
rechecked timing. Chuck from Abacus Racing (my engine rebuilders) made a
house call and left scratching his head. After weeks of this, I was leaning
over the fender as the engine was idling and I realized I could hear the
spark inside the distributor, which seemed kind of unusual. To make a long
story short, I found that the retard diaphraghm, which I had disconnected,
had apparently become deformed internally (gas got to it?) and was pushing
the breaker plate so far out that the distributor geometry was completely
out of whack. I could set the timing correctly, but the rotor was so far
from the posts in the distributor cap that the spark was having to jump a
great distance and losing all its oomph in the process. I removed the
retard diapraghm and replaced it with a small metal strut that holds the
breaker plate in a fixed position and life has been good for the fifteen or
so years since. The moral is that just disconnecting this expensive,
short-lived piece of crud is not good enough - get rid of it.
Mark Anderton
72 TR6
Virginia Beach
http://members.cox.net/andertonm/car_stuff.html
----- Original Message -----
From: <Acekraut11@aol.com>
To: <6pack@autox.team.net>
Sent: Saturday, May 17, 2003 11:58 PM
Subject: Carb Tune High Idle Update
> Hi List,
> Thanks to all who responded to my question regarding a persistent high
idle while trying to tune my rebuilt carbs for the first time. For all of
you fans that like happy endings you are in for a treat. After several
attempts, trying this and retrying that the culprit was none other than the
bypass valves. Thanks Hugh you win the prize.(check is in the mail) I know
when I rebuilt the carbs that I didnt change the internal settings, however
I believe that because the diagphrams were so old and cruddy that they were
essentially closed regardless of how they were supposed to work. My bypass
valves had the little brass discs that sealed the screw. Removed those and
adjusted them all the way tightly closed and presto, no more high idle. I
did manage to finish tuning the carbs and on the test drive was very
pleasantly surprised. Nice power all the way up through the gears and rpms.
Smooth, and no stalling when stopping.
> One thing I did notice about the car is that there is no vacuum lines at
all from the distributor to the carbs. What is the consensus of the list,
do others have the same setup? Should I be trying to replace what is
missing? I have a vacuum retard on the distributor, but no vacuum advance.
> Thanks again,
> Aaron
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