Ok I have this weird thing goin on with the timing on my 302. With the timing set at around 10 degrees and a timing lite attached, I rev the motor and alls fine, except when the motor returns to idle the timing is still at 30 degrees, WTH??? So I unhook the vacuum line to the dist and the timing returns to 10, plug the line back onto the dist and it stays there untill reving it up again. I have checked(visually) the vacuum advance mechanism and it all looks to be working smooth. Any thoughts???
do you have a handheld vacuum pump? if so pull the cap and pull vacuum on it. watch to see how it moves. and look to see if it returns after you drop vacuum.
I dont have a pump, so I just sucked on the end of the hose and was able to see the lever, and the cam move back and forth with no sticking,
with the vac hose off of the distributor, hook a vac gage up to it or plug with a finger. rev the motor up to 3000 rpm then let it return to idle. does the line still have vac. in it? if so the problem is in the carb.
By any chance is there a check valve in the vacuum line from the carb? It being a 76 there were a lot of vacuum lines that someone may have moved around. Make sure that the vacuum line goes to "ported vacuum" and is one continuous line. Just a thought.
