2000 yamaha 115 no power under load

[ragbul]

Ok as I turn to all of you boat engine guys when I have a question. I have a hurricane deck boat with a 2000 115 yamaha 2 stroke. Today I took the boat out on the lake and noticed it would not run under power. It was running fine and then all of a sudden it slowed down and died after about 3 minutes of WOT. I was able to get it going and it would go into gear and only get to about 1300 rpms. I limped it back in and now am confused on what could be the problem. I have recently just replaced the fuel pump and cleaned both carbs and have run it sense fine. Today when the problem started I noticed it would jump from 1300 to 2300 on the rpms with no change in engine noise or perfomance. If anybody has had this similar problem or one like it what should I be checking into. Also the boat runs fine at idle and will rev up out of gear. Let your braniac ideas start flowing.

 

[extreme01]

Re: 2000 yamaha 115 no power under load

ive had this happen it turned out that my fuel line connector was bad so check that seems a $10 part causes a lot of problems

 

[ragbul]

Re: 2000 yamaha 115 no power under load

ok after doing some work this morning my primer bulb stays hard and full, I have spark at all four plugs and they were all normal conditions. I let the boat idle for some time and then backed it out of the boat house and there were no problems in reverse. As soon as I put in in forward gear and try to give it gas it bogs down and dies. I am thinking that the carbs are going to have to be rebuilt again???? Anything else I should look into before cleaning and rebuilding the carbs.

 

[jerryz]

Re: 2000 yamaha 115 no power under load

Ragbul...I am dealing with the same problem, same motor, same boat. Please post your solution when you find it, I will do the same.

 

[Patrick Rhea]

Re: 2000 yamaha 115 no power under load

Ragbul...I am dealing with the same problem, same motor, same boat. Please post your solution when you find it, I will do the same.

I came here looking for the same answer today... Mine is dying under load now????

The other problem is out of water it revs just fine so it makes it hard to investigate....

 

[smoedog]

Re: 2000 yamaha 115 no power under load

carbs need a rebuild. I had an old glastron with a 4.3 merc and it would do the exact same thing, out of water or in idle it would be fine, as soon as you put a load on it, it would stall.

 

[jerryz]

Re: 2000 yamaha 115 no power under load

Smoedog is correct. I pulled the carbs on my motor and pulled them apart. The bowls were horrible. Cleaned the carbs, put them back on and the motor runs like new. BTW...unless your needles are messed up you don't need the full Yamaha carb kit. It has a bunch of parts in it that you wont need, unless you lose pieces from the tear down. Plus they carry a hefty $98 price tag...for each carb! Buy 2 bowl gaskets (still pricey at $37 each), everything else should be re-useable. Good luck.

 

[pappastratos]

Re: 2000 yamaha 115 no power under load

Same problem, same motor! Jerry, what are some tips/tricks on removing & installing carbs? What to watch out for while cleaning?
Thanks

 

[jerryz]

Re: 2000 yamaha 115 no power under load

Cleaning the carbs is pretty straight forward. Removing the carbs is a little cramped. When you pull the carb bowls off the carbs try to keep the gasket with the carb body and you might be able to reuse them. These were the easiest carbs I have messed with. An impact screwdriver is helpful on the brass caps. Clean all passages and blow dry with compressed air. Good Luck