I have a 2003 Mercruiser 4.3 L with a 2bbl Carb. It has a strange stalling issue which happens randomly at idle, partial or full throttle. When it is running, it runs great. When is stalls, it will stall a few times in a row and then run great for a few minutes up to 40 minutes of idle. I have run it at full throttle for 5 minutes or more.
I have replaced the distributor sensor, cap, rotor and plugs. It has a new water separating fuel filter and fresh oil change. I have poured the gas out of the fuel filter and there is no water in the gas. I by passed the oil sensor and it still stalls, I unplugged the shift sensor (did not shift it) and it stalled at idle.
It is currently in the Mercury boat shop and they are stumped. They have a fuel pressure gauge on it and it stays steady on my tank and the shop tank. They said when they have it hooked up to a shop tank and when it starts to stall they can save it by pumping a primer bulb. So they are thinking it is a fuel delivery problem and want to tear apart the carb, but I don't think that makes much sense, since when it is running it runs great. Can a carb have an intermittent stalling problem? I have never heard of such a thing.
I still think it is an electrical issue. Bad coil (not likely), bad ignition module (maybe, approx. $500.00). They don't have any spares to try. I am hoping they will test with new ones so I don't have to buy them it they are not the issue.
I need help before they charge me a fortune in labor trying to figure this out. This is the second time in the shop. They said it was the distributor sensor the first go around, but that was not it. Please help!!!
I have replaced the distributor sensor, cap, rotor and plugs. It has a new water separating fuel filter and fresh oil change. I have poured the gas out of the fuel filter and there is no water in the gas. I by passed the oil sensor and it still stalls, I unplugged the shift sensor (did not shift it) and it stalled at idle.
It is currently in the Mercury boat shop and they are stumped. They have a fuel pressure gauge on it and it stays steady on my tank and the shop tank. They said when they have it hooked up to a shop tank and when it starts to stall they can save it by pumping a primer bulb. So they are thinking it is a fuel delivery problem and want to tear apart the carb, but I don't think that makes much sense, since when it is running it runs great. Can a carb have an intermittent stalling problem? I have never heard of such a thing.
I still think it is an electrical issue. Bad coil (not likely), bad ignition module (maybe, approx. $500.00). They don't have any spares to try. I am hoping they will test with new ones so I don't have to buy them it they are not the issue.
I need help before they charge me a fortune in labor trying to figure this out. This is the second time in the shop. They said it was the distributor sensor the first go around, but that was not it. Please help!!!