engine bogs down

[halfpint1]

Early last month we had a warning buzzer that sounded all the time (overheat tone).We sent for the manuals for our engine a 1992 Mariner 40hp.Although they were informative they didn't really help me with what was going on with my engine. We had a mechanic check the engine and he said that the engine is not running hot. He unplugged both the overheat sensor and the oil sensor and the alarm still sounded.He said we had a bad alarm and replaced it. Yahoo low fee.No more beeping.However,the boat will start fine no problem but when we go to accelerate, the engine starts to die out and vibrates. This also happened the first time the alarm went off.If the alarm was supposed to be for overheat but it isn't overheating and it isn't the oil sensor what the heck could be happening? The mechanic is backed-up for about 5 days and can't check it out for a while so any helpful ideas would be appreciated. This is supposed to be my fishing vacation week---sorta sucks without my boat.

 

[achris]

Re: engine bogs down

I'd start with a compression test to make sure everything in that area is ok. Then I'd richen the carbs 1/8 turn and try again. If that doesn't fix it, strip and clean the carbs.<br /><br />Chris............

 

[funpilot]

Re: engine bogs down

Halfpint,<br /><br />Have you ever decarbonized your engine. You can stop at your marine store and ask for something that will disolve the carbon in your engine. You can spray it into the throats of the carbs, per the instructions, and finally 'flood' the engine out on the stuff. After letting it soak for the prescribed period, start the engine. There will be a lot of smoke, but the results might surprise you. Achris has some good advice also, but I might try the decarbonizing before I strip down the carbs.<br /><br />Good luck,