Hey folks! I have a nice puzzle for you OMC’ers...
Some backround: Boat's been converted to electronic ignition, lower cable changed, rebuilt the carb in the spring, new esa module installed a couple months ago. We've put plenty of hours on the boat since that work was done. Started, idled and ran perfect. The shifting, not perfect but the interrupt did work.
Given the boat is an ’88 with the original ply floor ‘n carpet, I go to GREAT lengths to keep it dry. The boat is never in the water when we’re not using it, always well covered when it rains, etc. I might have used the bilge pump twice in three years. Except last time we used it we got skunked and a bad rain cloud dumped a ton of water in the boat. We tried to dry it as much as possible, but I had no choice but to store it still kind of damp.
After 3 weeks in the shed, put the boat in the water, two pumps of the shifter (as usual) and it started right away. I usually let it idle for a bit then, away for a quick check ride. However this time the boat ran for about half a minute and the engine quit suddenly while still in neutral (not caused by shifting). I tried restarting and the engine fired up briefly and quit again. Couldn’t seem to get it to run again after that. I tried again several times with pauses in between and it always does the same thing. Runs for half a minute (700, 1500 or 2000 rpm) then dies etc.
Later, I somehow managed to keep it running long enough once and bring it up to temp by pumping the throttle as it was dying and it would fire back up. It was not graceful, but it worked. Once it was warm, it would idle easier and I noticed the following: Intermittently, the RPM gauge suddenly will climb from 7-800 RPM to about 1500 (while the engine actually goes down in RPM). It seems like a short or a bad ground somewhere causing some kind of load? When the engine’s cold, it chokes out easily. When it’s hot, it just makes it struggle / quit.
I thought maybe the boat needed a good shakedown ride so I tried to plane out but it kept cutting out before it got there. It wasn’t the typical ESA interrupt symptom, nor the “slamming the throttle open too quick” symptom either. Seems like something else is causing it...
First I thought it was a fuelling issue (like an air bubble in the fuel line?) but then that wouldn’t explain why the RPM climbs and engine stumbles at the same time... I wanted to bring the motor up to temp to help dry out the engine compartment.
Anything else you folks can think might cause this? What would you check or try next?
Thanks in advance!!
Some backround: Boat's been converted to electronic ignition, lower cable changed, rebuilt the carb in the spring, new esa module installed a couple months ago. We've put plenty of hours on the boat since that work was done. Started, idled and ran perfect. The shifting, not perfect but the interrupt did work.
Given the boat is an ’88 with the original ply floor ‘n carpet, I go to GREAT lengths to keep it dry. The boat is never in the water when we’re not using it, always well covered when it rains, etc. I might have used the bilge pump twice in three years. Except last time we used it we got skunked and a bad rain cloud dumped a ton of water in the boat. We tried to dry it as much as possible, but I had no choice but to store it still kind of damp.
After 3 weeks in the shed, put the boat in the water, two pumps of the shifter (as usual) and it started right away. I usually let it idle for a bit then, away for a quick check ride. However this time the boat ran for about half a minute and the engine quit suddenly while still in neutral (not caused by shifting). I tried restarting and the engine fired up briefly and quit again. Couldn’t seem to get it to run again after that. I tried again several times with pauses in between and it always does the same thing. Runs for half a minute (700, 1500 or 2000 rpm) then dies etc.
Later, I somehow managed to keep it running long enough once and bring it up to temp by pumping the throttle as it was dying and it would fire back up. It was not graceful, but it worked. Once it was warm, it would idle easier and I noticed the following: Intermittently, the RPM gauge suddenly will climb from 7-800 RPM to about 1500 (while the engine actually goes down in RPM). It seems like a short or a bad ground somewhere causing some kind of load? When the engine’s cold, it chokes out easily. When it’s hot, it just makes it struggle / quit.
I thought maybe the boat needed a good shakedown ride so I tried to plane out but it kept cutting out before it got there. It wasn’t the typical ESA interrupt symptom, nor the “slamming the throttle open too quick” symptom either. Seems like something else is causing it...
First I thought it was a fuelling issue (like an air bubble in the fuel line?) but then that wouldn’t explain why the RPM climbs and engine stumbles at the same time... I wanted to bring the motor up to temp to help dry out the engine compartment.
Anything else you folks can think might cause this? What would you check or try next?
Thanks in advance!!
