wont idle
#1
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Join Date: Nov 2008
Posts: 263
wont idle
the truck wont idle, its actin like its runnin way too fat, but its a 3310 vacuum secondary 750 and i just put size 77 jets, are those too big?
i dont think they r but i may be wrong.
it just wont idle right though, and its burnin way too rich and i can smell gas in the exhaust
please help
i dont think they r but i may be wrong.
it just wont idle right though, and its burnin way too rich and i can smell gas in the exhaust
please help
#2
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Join Date: Sep 2007
Posts: 4,137
Check the power valve. The jets SHOULD NOT effect on how it idles.If the powervalve is blown,or if it is opening at Idle, it will be 8-10 jet sizes too rich. Also if you have the speed screw turned in far enough to uncover too much of the transfer slot in the base plate,it will pull from the main circuit.
Did you use a new metering block gasket or reuse the old?Is it the correct gasket for that carb? Did you make sure there was no left over gasket stuck to the block?
Did you use a new metering block gasket or reuse the old?Is it the correct gasket for that carb? Did you make sure there was no left over gasket stuck to the block?
#3
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i just put a new power valve in it, i even called holley to make sure i had the right one, and to make sure i had the right jet sizes, which i do, it is a 3310 750 vac. secondaries, 6.5 power valve, and 74s in the front 77s in the back, 7 psi of fuel press. and have set floats properly, proper gaskets and made sure it was clean
im stumped the only other thing i can figure is ignition, could this be the issue, maybe not gettin enough spark
because today it would idle for like a minute before it would start sputterin and poppin through the exhaust, and smoke too,
im stumped the only other thing i can figure is ignition, could this be the issue, maybe not gettin enough spark
because today it would idle for like a minute before it would start sputterin and poppin through the exhaust, and smoke too,
#6
I had a problem with my Holley and that was that the rear 2 jets were stuck open. It didnt matter what the idle was adjusted to they just Pissed fuel down the carb. That might be something to look at.
#7
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Join Date: Sep 2007
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BOWHAY, what is your vaccume at idle with the trans in gear? 6.5 is the power valve that comes in them when new, but if you are below that with your vaccume it could be opening up.
Again, the main jets will not make it run rich at an idle if everything is set right...
Again, the main jets will not make it run rich at an idle if everything is set right...
#8
I WOULD TRY 68 JETS IN THE PRIMARY WITH A 3.5 POWER VALVE, THATS WHAT I RAN ON MY 383 ,, MY BUDDIES 454 RUNS 70 JETS AND RUNS A LITTLE RICH,,,,,OPINION JETS ARE TO BIG.... GOOD LUCK..
#10
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Posts: 263
ok so the secondary idea makes sence
well heres what was done before all this stuff happened, i had a 650 on the truck, wanted a 750 and a friend had a main body and base plate from one so i took my blocks and bowls and put them on this 750 body, i took out the flaps to clean them up and when i put them back in there was a visible gap around the secondary flaps, so i think what may be happening is that fuel is just runnin through the secondaries cus the flaps are open a lil bit
and due to the fact that i have a lopey cam could tht make it to where i need a different valve?
well heres what was done before all this stuff happened, i had a 650 on the truck, wanted a 750 and a friend had a main body and base plate from one so i took my blocks and bowls and put them on this 750 body, i took out the flaps to clean them up and when i put them back in there was a visible gap around the secondary flaps, so i think what may be happening is that fuel is just runnin through the secondaries cus the flaps are open a lil bit
and due to the fact that i have a lopey cam could tht make it to where i need a different valve?