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View Full Version : MOTOR SURGE PROBLEM

NEILES1
06-03-2004, 12:17 PM
I have a 1988 checkmate sportfire I/O I was cruising up the hudson last week and about 45 min into the trip my motor started surging at about 40mph. So I checked the engine found plugs ok. I just filled the tank right before launching. But it only surges at speeds above 35mph when cruising at slow speeds it rides fine. It may be the fuel pump or the fuel filter if anyone has experienced it or has some advise please inform. thanks.
NEILES1
06-03-2004, 12:17 PM
I have a 1988 checkmate sportfire I/O I was cruising up the hudson last week and about 45 min into the trip my motor started surging at about 40mph. So I checked the engine found plugs ok. I just filled the tank right before launching. But it only surges at speeds above 35mph when cruising at slow speeds it rides fine. It may be the fuel pump or the fuel filter if anyone has experienced it or has some advise please inform. thanks.
Eriktheviking
06-04-2004, 12:12 AM
How about the plug wires and the cap? Could be a cylinder intermitently firing.
BOB'S 283
06-04-2004, 06:44 PM
sounds like more of a fuel problem to me . water seperator (sp)is an easy place to start.
vinny p.
06-04-2004, 09:42 PM
I agree.. Most probably is a fuel problem. You did not specify the type of motor and carb. In any case, the procedure is the same to diagnose the problem. It would be best if you could get a fuel pressure reading at speed. That would tell you right away if it is a delivery problem or a carb problem. If this is not possible, then first start with the easy things. Change both of the fuel filters. The small one in the carb and the fuel water seperator. Check for any damage to the fuel lines. IE: bent or colapsed lines. If the carb has not been done in a while, the next cheapest step would be to pull the top off and check out the bowl for dirt. At this point it would probably pay to just put a rebuild kit in the carb. They are cheap enough. Make sure you check the float for sinking. If it a phenolic float, don't even mess around with it, just change it. If it is copper, check for leaks, and re-use it if it is good. If the problem still perisists, the next step would be the most expensive one. Change the fuel pump.