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inconsistant idle ......

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zimmy

zimmy

Jedi Knight
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hey guys, i fixed my blinkers finally with a hot jump from the ignition to the blinker connect, and if im correct it is drivable from there, so im trying to get it running good so i can start driving it to work instead of my gas guzzler..

im trying to get my carbs set better, but during idle, my motor drops RPMs for a few seconds then goes back to normal....
it does this every 10 seconds or so..im guessing...
it doesnt affect drivability as far as i can tell...
any ideas? fuel filter maybe? ................zimmmy
 
sticking dash pot.
 
dash pots fine....
i checked my plugs and 1-3
were running hot and 4 was wet!
so i moved plug 4 to 3.......
opened the fuel to 12 clicks
and it ran better, without the stutter.
it still doesnt run smooth though, so i
checked the plugs again and 3 is now wet!
so im guessing i have a faulty plug...
whata relief, i guess :wink:
anyone agree? ...z
 
so, i changed the plug and it was running good, and passed all the test
when i removed each plug wire, but it started smoking grey smoke with a slight cough here and there.........
i adjusted the timing to see if i could clear it up, but no luck...
so i sat there for about 15 minutes, then started it and drove around
the block.....to my surprise it had alot more spunk and the smoke is gone!
whats going on here? it seems fine now, although idle is 1450 rpm and
the air adjustment screws are all the way lose ....
im sure its still not tuned proper, but there IS improvement in power.....z
 
All those symptoms sure sound like a vacuum leak.
 
I have to agree with "Bayless", sounds like a vacuum leak. Possibly something has worn out and allowed a vacuum leak to occur. My Weber was doing that and sure as ever there was a leak.
 
if it was a weber i would suggest that you check the nut on the throttle shaft...you know the one they tell you not to over tighten. I have had that loosen up and cause idle problems as well. but it is not a webber is it?



m
 
I think we all agree it sounds like a vacuum leak. I had this same problem with a set of SUs I rebuilt recently and it turned out that one carb was sucking air around the throttle shaft.
 
Is there a bench test for throttle shaft wear? HS2 in my case.
 
Spray carb cleaner around the throttle shafts (outside the carb, of course), see if the idle changes. If it does, you have worn throttle shafts & bushings.

Colin
 
But no way to check on the bench, so as to address before install? See if there is any "play" I guess?
 
Bench test.... well, since the shafts generally wear more than the body, I suggest measuring the shafts.
 
drove it to work this morning...
non complaints other than my sticky tranny.
im sure it could run better though...
ill try the carb cleaner and see what happens.
i can just tell u now , theyre old and definitely
need rebuilt ....thx guys ..z
 
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