65hp Mercury 4cyl 650

[lodown]

I was wondering if the wrong spark plugs were in the motor would it cause it to lose power? When i run at full throtal for a minute or so it starts to baug down and lose power then i back off the throtal down to almost an idle and wait a few and then it will go full rpm again for a few min then it baugs down to an idle rpm any body know what would cause this i'm not sure if the plugs are right.

 

[roscoe]

Re: 65hp Mercury 4cyl 650

Champion 5898

The problem you describe sounds like a fuel problem.
The float bowl on one carb is not filling fast enough.
Try squeezing the fuel primer bulb when the motor is slowing down. See if the rpm pick back up again.

Check all the fuel lines for leaks, they could be sucking air in, or dripping fuel out.

Could be a sticking float in the carb bowl, requiring a rebuild.

Or could be a weak fuel pump, requiring a rebuild.

 

[rickdb1boat]

Re: 65hp Mercury 4cyl 650

Might be overheating too..

 

[lodown]

Re: 65hp Mercury 4cyl 650

Thanks i'll give the fuel lines and carb floats a check. I tried squezing the primer bulb when it started losing power but it didn't help any. I pulled the plugs when i got home and they were kind of wet all 4 and they looked liked they were all burning the same for the hour they were in, a little brown tint but wet. it had some autolight 303 in it.

 

[lodown]

Re: 65hp Mercury 4cyl 650

I put a new water pump in it, the water felt cool coming out the exaust on the back but nothing coming out the tatle tale. The head feels cool when i have it running with the hose atatchment hooked up.

 

[lodown]

Re: 65hp Mercury 4cyl 650

Which spark plugs should be in this the champion 5898 or champion j4c ? I have been told those two differant ones.