what is the best way to adjust a q-jet how many turns out to start before i throw a vacuum gauge on it?where do i hook one up on the carb?there is no vacuum ports except where the the choke diaphragm connects to the car?none on the back of the carb either?any help and suggestions appreciated. Thank you
George, Passenger side nipple should be manifold vacuum. If you don't have one, tee into the vacuum break line.
Larry what exctly is that?should i unplug the choke diapragm and plug the vacuum gauge there?how many turns out should i start?sorry for the dumb questions but i am not familiar with q-jets. Thanks
George, On most Q-jets I have seen, there are 2 nipples in the front of the carb. One is ported(drivers side), and one is manifold(passenger side) The ported one usually goes to the vacuum advance on the distributor. Start with 1 1/2 turns out on each mixture needle. Turn them out 1/4 turn at a time until you get the highest vacuum/RPM. Try to keep the left and right one as equal as possible. You can use the one from the choke pull off if that's all you have, it's no problem.
the other thing i notced is when the fast idle and choke are applied when cold it runs shitty and blows smoke out the exhaust then when i apply gas it clears out and runs smooth what might that be from?is there a choke adjsutment on these carbs?
George, That choke diaphram. Is it working? Look at it with the engine running. Is the plunger retracted? If not it is defective. One of the things it does is open the choke a little after you start it cold. This allows the engine to run at a leaner mixture without loading up. The dchoke diaphram also holds the air valves closed until you nail it. If it is defective, the motor will bog.
I`m petty sure it was working but i`ll double check,if it is working is there anything else to look at? Thanks
Yes, If it is working, verify that it is opening the choke enough. Set the choke without the air cleaner on. Start the engine and watch the choke blade. When you set the choke, the blade should close completely. Once the engine starts the blade should open some and then the diaphram should open it some more. If opening the blade with your finger makes the engine run smooth, bend the linkage so that the diaphram opens the choke blade more. The choke blade is closed too much and the engine is running too rich and loading up.
