Trucksareforwork
Full Access Member
- Joined
- Feb 22, 2022
- Posts
- 245
- Reaction score
- 475
- Location
- Spartanburg SC
- First Name
- Geoff
- Truck Year
- 1985
- Truck Model
- C10
- Engine Size
- 305
So you have fuel and spark. If I read this correctly, you are sure that you have power to the spark when key is on (not cranking) and the engine dies when you let your foot off the gas.
To get it to idle the next thing is to check whether all the vacuum ports are plugged up. A large enough vacuum leak will cause it to die at idle.
Then, you can check whether your idle is set high enough on your carb both with choke on and with choke off.
Then be sure your timing is set high enough for happy idle. Some engines like a lot more timing than what factory used to say.
I’m probably out of order here. If it were me, I think I would look at all possible vacuum ports on the carb and intake manifold (don’t forget the intake) and ensure they are capped. Then turn the idle screw way in so that the carb will give plenty of fuel and air to stay running. Then try to get it to run long enough to adjust timing with a light.
Once you get it to stay running you can dial in timing, idle mixture, and idle, and check for smaller vacuum leaks with some carb cleaner sprayed around the base of the carb.
To get it to idle the next thing is to check whether all the vacuum ports are plugged up. A large enough vacuum leak will cause it to die at idle.
Then, you can check whether your idle is set high enough on your carb both with choke on and with choke off.
Then be sure your timing is set high enough for happy idle. Some engines like a lot more timing than what factory used to say.
I’m probably out of order here. If it were me, I think I would look at all possible vacuum ports on the carb and intake manifold (don’t forget the intake) and ensure they are capped. Then turn the idle screw way in so that the carb will give plenty of fuel and air to stay running. Then try to get it to run long enough to adjust timing with a light.
Once you get it to stay running you can dial in timing, idle mixture, and idle, and check for smaller vacuum leaks with some carb cleaner sprayed around the base of the carb.
