Full Throttle Engine Bogging

[Alain_North Ontario]

Hello,
2005 115hp 4 cylinder four stroke.
Last fall I took out my boat at least 4 times and had this issue. The engine started fine, idled fine, left the dock fine and as soon as I would give it full throttle to take off the engine would start to bog down, go to 3/4 throttle and engine worked great. I would be able to drive that way with no issues as long as I didn't give it full throttle, I would drive for over 20 minutes and still no full throttle. I would stop to fish and after restarting the engine it would work perfect at full throttle.
Any ideals on what could be the issue.

Thanks
Alain

 

[bilge rat jim]

Any alarms from your remote / smartcraft?

 

[Alain_North Ontario]

Absolutely no alarm,

 

[bilge rat jim]

So lets find out if this is fuel or ignition related. Probably the easiest place to start is testing for consistent spark. Use an inductive timing light to check for spark on each cylinder as the problem occurs. If you seem to have spark on all cylinders, the problem is likely fuel related.

 

[Alain_North Ontario]

Thanks a lot, because the problem accurses @ full throttle can this issue be reproduced in a marine shop or will have to be done on open water?

 

[bilge rat jim]

Probably best to do it in the water (with 2 people- one driving, the other watching the timing light pulses.) Even in a test tank with a test prop, you may not be reproducing the actual conditions.

 

[Alain_North Ontario]

Thank you very much, now just have to wait for open water