Motor Chockes when i put the hat on

[gavbpr]

Hello:
I have a 2000 15HP 2 stroke merc. losses power when i acelerate and when i get it to run with out lossing power, when i put the cowling on it gradually slows down till it goes off usually with a lot of coughing and trembling.
Any Ideas on what to door what can be wrong?

 

[Silvertip]

Re: Motor Chockes when i put the hat on

Exhaust leak. With the cover off there is enough fresh air to allow it to run. With the hood on the exhaust is sucked back into the intake and she dies. Power head base gasket is apparently shot.

 

[gavbpr]

Re: Motor Chockes when i put the hat on

I forgot to mention that this is hapening wile i am running it in the test tank.
Also coul it be that the carb. nedds adj. i replaced the gaskets to it and was running fine till the other day. Maybe prob. with gas tank, line or some thing? any other thing i should look for? Gasket for head looks ok to me. Also i notised vapor comming out the drip hole but when i accelerate it water comes out ok. It has a termostat that is wy i am not sure if it is suposed to work that way.