35hp Mercury: serial no. A123302

[SteveGsch]

I believe that my motor is a 1985, I've had it running this summer and everything seemed fine. One day it I tried giving it full throttle and it would not speed up. It runs rough and has a noise in the top of the motor. It does not sound like a rod and it does this while in neutral. I replaced the spark plugs and rebuilt the carburetor to see if that would change anything but it did not. I checked if there are any cracks in the fly wheel but it is fine. Any information on what the problem could be would be very much appreciated.

 

[racerone]

Check for or have a shop look for a broken crankshaft.

 

[fastjeff]

Might have a bad top bearing. You can remove the bearing carrier without splitting the crankcase and see what's happening.

Jeff

 

[SteveGsch]

Might have a bad top bearing. You can remove the bearing carrier without splitting the crankcase and see what's happening.

Jeff

Is there any trick to getting the top bearing cap off? Thanks!

 

[fastjeff]

Yeah: Loosen the two or three top crankcase to block bolts.

Jeff