1988 Merc 25 problems

[joho5]

My dad has this motor and we are having troubles. It starts and idles fine most of the time, but it wont top out. It runs smooth and sounds fine, but just wont get to the top end rpm's. We changed out the coils because they were cracked.

The guy he got the motor from has a Johnson/Evinrude gas fitting on the tank. So the gas line has 1 end Johnson/Evinrude and then the other that connects to the motor is Mercury. Could that be a problem with air?

the next thing we are going to do is pull and clean the carb.

If any has any other suggestions about why it wont run at top end, please let me know. I only own Johnson and Evinrudes so I am inexperienced with a Merc motor.

thanks

Matt

 

[Laddies]

Re: 1988 Merc 25 problems

It sounds like a plugged high speed jet.

 

[joho5]

Re: 1988 Merc 25 problems

the carb is apart now...which jet one is the high speed jet?

also, do you know the needle setting for this motor? I pulled it out, but when I put it back in, I dont know where to set it.

is it just 1 1/2 out, then go in till it spits, then back it out till it gallops, then find the happy medium?

sorry, we dont have a manual yet.

Matt