My 1996 90hp Tohatsu wont get to proper RPM

mugen24

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When i first take off its jumps out of water for a sec, than dies down can anybody help, it run smooth but not fast.
 

pvanv

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Re: My 1996 90hp Tohatsu wont get to proper RPM

I take it you have an old M90A? Did you check for a spun prop? When was the last carb cleaning? When was it last checked for proper link and sync? Is the fuel filter clean? If this seems daunting to you, see a dealer.
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

I take it you have an old M90A? Did you check for a spun prop? When was the last carb cleaning? When was it last checked for proper link and sync? Is the fuel filter clean? If this seems daunting to you, see a dealer.
Yes its is am90a i cleaned the carbs twice and filter, yesterday it rev higher but it was like a car with rev limit at full thro it da-da-da-da- if that makes sense than thro back and its wont rev up again.
 

pvanv

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Did you clean the carbs by soaking them for 4 hours in carb dip? If not, start there. Also check link and sync.
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Did you clean the carbs by soaking them for 4 hours in carb dip? If not, start there. Also check link and sync.
Ok i will soak them again, How do you you check proper link and sync.
 

pvanv

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Full sync info is in the Factory service manual; trying to describe it on the forum would be difficult.
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Full sync info is in the Factory service manual; trying to describe it on the forum would be difficult.
Had wife drive boat at full thro and i put a rag over each carbs and the bottom one rev up boat, so im going to soak carb again hope this works i soaked that one all night and day.
 

pvanv

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Re: My 1996 90hp Tohatsu wont get to proper RPM

What did you use for carb dip? Did you blow out the soaked carb with carb spray?
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

What did you use for carb dip? Did you blow out the soaked carb with carb spray?
Yes i took bottom carb apart and found float was full of gas, Just order rebuild kit But i dont understand y if i put rag over carb rpm go up i thank it should be flooding? i bought the gallon can cleaner and blowed compress air thru and carb cleaner.
 

pvanv

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Re: My 1996 90hp Tohatsu wont get to proper RPM

If choking with a rag helped, you were not delivering enough fuel, so it was not flooding, but rather starving for fuel.
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

If choking with a rag helped, you were not delivering enough fuel, so it was not flooding, but rather starving for fuel.
yes i just rebuilded the carbs yesterday a little better but the bottom carb still starving for fuel i only thing ive not done is replaced fuel pump?
 

pvanv

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Possible. If it seems to "run out of gas" after a few minutes at WOT, you might be delivering insufficient fuel. I would check it per the manual.
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Possible. If it seems to "run out of gas" after a few minutes at WOT, you might be delivering insufficient fuel. I would check it per the manual.

Paul hpe this sense when i give WOT it jumps out of water for a second than dies off but it is smooth with no hesitation just not reving up, it like its maybe going into safe mode that dont let engine rev up but to certain RPM.
 

TOHATSU GURU

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Clean the carbs again and again and again..............and again.
 

mugen24

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Re: My 1996 90hp Tohatsu wont get to proper RPM

Clean the carbs again and again and again..............and again.
Yes i put a new fuel pump on and still same i took choke link off bottom carb and zipped tied it close, it and got 4 more MPH, but cant get WOT because it like it got REV limiter on it, its going Da-da-da-da-da. are still starving for fuel, going back in carb today and clean it
 
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