Just an update as to my progress (and lack of) with the ZS carb saga. Once
again I have pulled the rear carb after 'cleaning' of the black specs and
reinstallation provided 'No Joy'. One interesting tidbit with regards to
mixture and backfire behavior is "if it backfires thru the carb - its too
lean, if it backfires in the exhaust - its too rich".
To review, the car will start and run, more often than not immediately(basic
mixture OK)- but the idle fluctuates wildly.
My Thinking -my mental picture is: float dropping-fuel bowl filling, shuts
off, MAYBE VALVE STICKING-then opens, float dropping, MAybe float doesn't
close needle jet-floods, then closes, CYCLE REPEATS).
When I goose the butterfly throttles- she'll either zoom up wonderfully,
usually if I add choke, or stall and die-usually with a backfire- a bad
backfire-usually in the exhaust or behind. Sometimes I see floooding
(leaking gas from the mouth- as if the float is not closing the float valve,
or the float valkve is not closing), but not always. This again points to
the float valve/jet or the float.
Conversation with Joe Curto Wednesday-he suggested weighing the float-said
it should be about 15 grams, no more-. He said get back to him in a couple
of days, if its not the float- he'd send me another float valve/jet.
I pulled the valve cover to check for bent pushrods and check the valve
train operation- no problem.
So last night I swapped an old float valve- and the car actually,
periodically, ran a little better- enough to move it 'up the incline in the
drive/parking pad, about two feet at a time-but more than I could do since
the Tow Truck returned her/us home from the TR aborted TRA 2000 trip- so at
least I can put another car behind it again, and keep one more off the
street.
So at 10:30 PM last night, I pulled the carb again, and the float bowl was
again full- (hate the new gas effervesence- was much better in the 60's and
70's.
Packaged up the float in paper towels and a ziplock to take to the post
office to finagle a 'computerized weigh job'. This mornig I got the float
weighed (at the Post Office) = .5 ounces, which converted = 14.1747 grams.
Got to work, Called Joe- he says that should be OK then, he'll send me a new
float valve but says he just had a problem with (carbs) on an ALVIS- doing
the same thing and he's convinced the problem is, as it was on the ALVIS- a
sucked in intake manifold gasket.
That certainly would explain the 'starvation and lack of syncronized hiss
form the thottle mouth'.
So that's what I'll be doing this evening - taking the intake manifold off
to check the gasket.
(All the manilfold attach 'clamps' and nuts appear and tested 'tight'- but
one never knows with a Triumph!
Will advise!
Sherman
Sherman D. Taffel
Columbia, MD
CT40054L
L=Longing to make Bowie with the TR
|