85 hp force hesitates at full throttle

[electriciansmate]

My engine starts and runs great until I throw into full throttle. It then revs up and down until I back off it a little. Then it cruises fine. I want full throttle. Any ideas of what I can do. I've gone to mechanics and they wont even look at a Force engine. HELP!

 

[steveclv]

Re: 85 hp force hesitates at full throttle

Almost certainly it's fuel starvation.

Check the fuel pump diaphragm - they are about $5 to replace and the pump is a 2 stage pump so will run on one side, just not very well.

Also check any filters (mine had a small screen in the pickup tube in the gas tank that was completely gummed with varnish) and hoses for any pinhole leaks - if in doubt replace them as they are cheap enough.

Try that first before you are even tempted to touch the carburetors.

 

[jerryjerry05]

Re: 85 hp force hesitates at full throttle

Possible the vent is clogged.J

 

[rugman]

Re: 85 hp force hesitates at full throttle

My 85hp did the same thing, and I found that one of the small air jets on the side of the top carb had fallen out. I found it laying in the engine. It was stripped, so a drop of jb weld to hold it in and it runs like a new one!

 

[electriciansmate]

Re: 85 hp force hesitates at full throttle

hey thanks. I have read a few other replies you have wrote. you seem very knowledgeable. But not sure what you mean vent is clogged. on the gas tank? or where?

 

[steveclv]

Re: 85 hp force hesitates at full throttle

Yes, he means on the gas tank

If it's an inboard tank - there is a vent that goes from the top of the tank to the transom - it allows air in as the engine pulls gas out.

Simply a case of removing the pipe and either replace it or blow through it to make sure it's clear and check the tube is clear in the top of the tank.