1989 5.0LX four barrel Rochester carb. After fully warm, no throttle advanced, engine cranks for maybe 10 seconds before gradually starting. Runs great after finally starting. It used to start much quicker. I will put a carb rebuild kit in but I don't think that will improve it since it runs great after starting and starts great when cold. Wondering if there is a vacuum diaphragm that activates the accelerator pump at initial cranking that could be leaking????
The accelerator pump is not part of the idle circuit so I doubt it has anything to do with the issue. Most common cause is fuel dribbling after the engine is shut off. Float to high or other idle circuit issue. A proper rebuild is probably in order. What carburetor do you have?
I have a Rochester Quadrajet. when it does start it doesn't smell rich. It's seems more "fuel starved" because when I give the throttle a little push forward, it starts immediately. I'll put the carb rebuild kit in and make sure the idle jet orifices are cleaned out real good. I can't remember if I need a special idle jet screw tool (I don't have the boat near), Would you know?
Also, thank YOU for the advice on the vacuum diaphragm. So now I know the diaphragm is just the choke "pull off"
Check your throttle shafts for excessive play. I put bushings in my quadrajet shafts on 5.0LX and was able to get idle down to 400 rpm. Excess clearance makes the mixture screws ineffective. Allows air to bypass idle circuit.
5.0 LX hard starting when warm
Linear Mode
