Runs fine at low speed cuts out at high speed. new hose…new gas…only does it some times. Pumping the bulb when it cuts out doesn’t help. Any ideas? high speed jet on carb? Diaphram in fuel pump? Power pack?
John
Does it start again right away after it cuts off?
Key West 19’6" CC 115hp Merc
14’ Fast Craft w/ 60hp Merc
It starts right back up.
John
I am by no means an expert, but I do know when my 115 was shutting off after running for about an hour, it would not start up for about 20 minutes. Ended up being the power pack. Usually, if the problem is heat related, it would require time to cool down. I would lean more towards a fuel issue.The first ting I would try is to pull the carbs and clean/check for worn parts. I doubt you have a clogged high speed jet because that would most likely make it run rough all the time. Possibably trash in carbs? Couldn’t hurt to clean them and not that hard to do. That would at least eliminate the carbs from the equaasion if it didnt fix the problem…
Key West 19’6" CC 115hp Merc
14’ Fast Craft w/ 60hp Merc
What type of fuel tank do you have. I always ask what some deem stupid questions but have had problems with small tanks before. If the metal 6gallon tank pull the the connector section off and check the brass pickup tube for a crack. If the plastic tank it can be the same thing. Had a 15 horse that would run with a full tank but get down around 3/4 it would act like it ran out of gas. Ran ok at lower speeds.
1720 KW 110 Johnson
16’ Bonito 65 Johnson
What type of fuel tank do you have. I always ask what some deem stupid questions but have had problems with small tanks before. If the metal 6gallon tank pull the the connector section off and check the brass pickup tube for a crack. If the plastic tank it can be the same thing. Had a 15 horse that would run with a full tank but get down around 3/4 it would act like it ran out of gas. Ran ok at lower speeds.
1720 KW 110 Johnson
16’ Bonito 65 Johnson
Also, hope you have been using non-ethanol gas. Ethanol can eat up/dissolve lots of older motor parts and also mess up most of the newer ones if not used up quickly. It could be a bad spark plug wire if it’s an older model where the spark advance is controlled by the throttle. Check spark plug wires for wear if they move when you advance throttle.
All great advice…will work on it this weekend. Thanks for everyone’s input.
John