99 yamaha 90 problems

[highrisk]

I just bought a 90 yami and out it on my boat. It idles fine no problem doesn't get hot out of the pee hole but today is the second time it has been out and at first is wouldn't go past 2000 rpm and when it did it start missing real bad. So I kept running it and it cleared up put it still had no power and would barely put my boat on a plane and then once on a plane after about 5 min or so the motor just started Loseing power so I slowed it down to a idle and the water out of the taletell was hot as hell and steam was coming out of the exhaust ports. I am new to boat motors so I don't know where to start any help would be great!!!! Thanks I'd there's any more into you need please let me know.

 

[flyin4delta]

Re: 99 yamaha 90 problems

could be leaning out wayyyy too much. I would stop running it until you have checked into it.
Pull your spark plugs and see if you have and coloration.
Go here and check your plugs against this:
http://www.angelfire.com/fl4/pontiacdude428/Readplugs.html

 

[highrisk]

Re: 99 yamaha 90 problems

Thanks i will check that today. I had a friend tell me it could possibly be the head gasket? Could this be possibe as well? So if it was running way to lean could this cause it to lose power while running and the steam out of the exhaust ports?

 

[highrisk]

Re: 99 yamaha 90 problems

Forgot to mention its a 2 stroke 3 cylinder.

 

[highrisk]

Re: 99 yamaha 90 problems

check the plugs and all were brown or a little darker with a little bit of oil on them.

 

[highrisk]

Re: 99 yamaha 90 problems

Anybody???