Engine starts real rough
Thread Starter
Racer
Joined: Mar 2009
Posts: 278
Likes: 14
Engine starts real rough
Hey Guys,
Question for you, on my 69 BB 390 horse, when i go to start it after it’s been sitting (cold) few days, week etc. It turns & turns & turns and then it will start, but i have to keep giving it gas in order to keep it running it seems until it’s warmed up. At that point it runs well to the point of not stalling out once it’s warmed up.
Sparks and points are new.
What else can i check or do? I'd rather not take it in to have somebody do guessing games on my $$.
Any ideas would be appreciated.
Question for you, on my 69 BB 390 horse, when i go to start it after it’s been sitting (cold) few days, week etc. It turns & turns & turns and then it will start, but i have to keep giving it gas in order to keep it running it seems until it’s warmed up. At that point it runs well to the point of not stalling out once it’s warmed up.
Sparks and points are new.
What else can i check or do? I'd rather not take it in to have somebody do guessing games on my $$.
Any ideas would be appreciated.
Very good place to look for that type of problem.
Burning Brakes
Joined: Apr 2007
Posts: 1,186
Likes: 41
From: Pinecrest FL
2015 C3 of the Year Finalist
The next time you let the car sit for a few days, put a small amount of fresh gas into the carb and see if it starts right up.
If you have no issues with a cold start and gas added directly into the carb then your fuel bowl plugs are likely leaking and the fuel is drying up. Might need to have the plugs re epoxied and should take care of the problem.
Gary
If you have no issues with a cold start and gas added directly into the carb then your fuel bowl plugs are likely leaking and the fuel is drying up. Might need to have the plugs re epoxied and should take care of the problem.
Gary
Pro
Joined: May 2011
Posts: 581
Likes: 5
From: BC
The problem with the rough cold running is most likely going to be the choke pull off. Not sure what you mean by having to feed it gas to keep it running, but if you are having to "feather" the pedal, meaning a constant short pumping or constant movement of the pedal to keep it running and when it dies it does so suddenly, the vacuum break is pulling the choke off too far off creating a lean condition. Operating the accelerator pump in the carb is compensating for that.
If, on the other hand, the engine is loading up and slowing down until it starts chugging and you keep it running by raising the rpm and holding it at a very fast idle until it clears out then it starts over again, it is too rich. Either the vacuum diaphragm has a hole in it or is adjusted incorrectly and not opening it enough.
This is an issue easily dealt with without having to o'haul the carb. With a little more info we can walk you through the repair.
Steve g
If, on the other hand, the engine is loading up and slowing down until it starts chugging and you keep it running by raising the rpm and holding it at a very fast idle until it clears out then it starts over again, it is too rich. Either the vacuum diaphragm has a hole in it or is adjusted incorrectly and not opening it enough.
This is an issue easily dealt with without having to o'haul the carb. With a little more info we can walk you through the repair.
Steve g
