Check on the fuel system for any restriction. Did you overheat the
engine and possibly warp anything? How low was the water when you
refilled it? If it got hot, have you done a compression and leak down
test since? I assume no water in the oil and vice versa.
Fuel, fuel delivery, fuel pump, floats and the fuel bowls should be
checked. Check to make sure the carbs are still synchronized. You can
use the fancy ass vacuum gauge with the rising ball or the old fallback
of shoving a hose in your good ear and compare the sounds from one carb
to another by placing the other end in each carb with the engine running
at idle. Then try it at a partial throttle opening. It's more accurate
than you might think. If the linkage has slipped, having the carbs out
of adjustment will cause the type of problem you describe. If you made
it all the way back, it's likely not something major, that's the good
news! Also, you might try changing the coil after checking the points
and timing. A bad coil can cause even the strongest soul to tear hair
out in trying to diagnose it. I know this first hand.
Do you have an EGT gauge in your car? That would be a great indicator of
what exactly is going on in terms of combustion and will also be a dead
giveaway when the carbs are not both doing their job.
This is kind of like the Chineese menu, choose from above. Pretty sure
it's one of the above. I don't mean to insult you if you already have
done the above. Glad to elaborate if you can give a bit more
information.
Best of luck.
Russ Moore
-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net]On
Behalf Of Richard Taylor
Sent: Tuesday, July 29, 2003 10:39 AM
To: fot@autox.team.net
Subject: barking carbs
FOTers
Last weekend I competed in the VDCA event at the Barber Motorsport Park
in
Birmingham, AL. Beautiful weekend and a terrific track but I came home
early
with a curious motor problem.
On the track at full throttle I first lost one, then a second then a
third
cylinder until the engine quit entirely. After a ten minute rest the car
restarted and struggled (ran roughly) back to the paddock. It was low on
water. I let it cool over night and started it the next morning. If I
revved
the motor slowly, it would come on up to full rpms. However, if I blip
the
throttle quickly, it stumbles and barks fiercely out of the velocity
stacks.
I retarded the timing but nothing changed. I checked the movement of
the
carburetor pistons and they look normal. So I packed up my stuff and
drove the
150 miles back to Atlanta in OD ( 2500 rpms, +60 mph). Temp and oil
pressure
was normal and there was no measurable loss of either fluid. On uphill
grades
(i.e.., under load) the barking carb syndrome would return.
The internals of the motor sound normal.
Any ideas of where to start looking? I'm kinda puzzled.
Richard Taylor
TR-4 Atlanta
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