(1985) 125 over heating

[jhaley59]

OK, my problem on a 1985 125 force is; after running about 30 minutes, we idled down (twin 125's) and the buzzer went off on right unit. Let unit cool down, still would not start. I have no history on boat, previous owner bought it and never put it in water. The unit that over heated had new gaskets and impeller installed. (Ran fine on muffs, I just thought time to replace impeller). Stopped by dealer on way home to ask advise, he didn't look at boat and said it was a blown head gasket. Any Ideas before I start tearing into it in the morning.

 

[Lwapo]

Re: (1985) 125 over heating

Easy quick checks...

Check compression. Easy test for a head gasket. If you don't have a compression tester, you can usually get them for like $20.

Also, check your impeller. If you install them wrong, you can snap off a couple fins and ruin your water pumping ability.

I'm not very familiar with your motor and I'm no expert... but those are prolly two good areas to start!

 

[Frank Acampora]

Re: (1985) 125 over heating

First before assuming the worst, check the obvious: When an engine does not start, check for spark first as the ignition system is most vulnerable and failure prone. Then check for fuel supply. Then check compression. If an engine has all three, it MUST start and run. Compression can be low and equal, but if one cylinder is much lower than the others, the first thing to check is the easiest: The head gasket.

Now: the engine that overheated MAY have damaged a head gasket, but then again, it may not have. So: Follow the logical order of testing and let us know what you found.

 

[jhaley59]

Re: (1985) 125 over heating

Thanks, just odd both motors rand great for about 7/8 miles. Ran one leg up river idled checked ever thing then ran second leg back idled for several minutes then buzzer went of, I shut down one engine let cool. Loaded boat on second. The engine cooled down but want start now so Ill go through the list tomorrow, starting with thermostat and go from there.

 

[jhaley59]

Re: (1985) 125 over heating

OK pressure tested lower cylinder 90 lbs but didn't get good seal going to have to re-thread spark plugs (put insert), also had thermostat cover off. When pulled cover no thermostat was installed. Next thing pull lower unit and recheck previous impeller change.