Can you help with starting probs.

[Anonymous]

I am having a problem at times starting my car. Half the time it starts ok the other half of the time (usually if I give it too much gas) it will puff a cloud of smoke out of the carb and let out a belch. When it starts it runs fine. I am running a carter yf out of a late 60's ford with a d2 setup. Just replaced the timing set and balancer which I thought may be part of the prob, but it still happens. Right now the car is running with a very smooth idle of 700 rpm and 12-14* advance. I do have a light and check timing that way.

What could it be? How do I adjust air fuel mix? Could that be the prob?

 

[Anonymous]

If you are getting a smooth idle at 700 rpm, then it sounds like your fuel mixture may be OK. Check to see what your timing is with the vac hose connected to the distributor. It may be providing too much or too little vacuum advance at idle. It depends on the vacuum cannister and the distributor. The vacuum advance of some emissions era distributors was greater than the non-emission points type distributors. You would like to see something in the range of 24* total advance at idle. If the reading is too high look for a ported vacuum source to connect the hose to or if equipped adjust the spring tension on the vacuum cannister via a hex key in the cannister's nipple.

 

[Anonymous]

Spyke;

Try turning the carb's air screw in about 1/2 turn to see if it makes a difference. This is a large change, so it should change the way things run. If it does not make much change, turn it in another 1/2 turn, check again. If you get all the way in and it's still running, then the power valve is worn out inside the carb and you will need a carb rebuild.

The symptoms you describe might be a worn or nearly worn power valve.
This is one way to check.

 

[61Futura]

Too much advance could cause an occasional back fire, but run good once the engine starts. I've got some fine tuning to do yo my 170. It doesn't like much advance at idle right now.