Honda 4 Stroke Troubleshooting

I have an 82 Honda 100 CDI 4 Stroke motor which isn't pumping water. Any good troubleshooting tips I should take?

I don't have a shop manual so where could I find one and also where is the best place to get parts for these motors?

Check/replace the impellor.

Do a quick search for manuals. Believe Jim has a link to the SELOC manuals, I have gotten a few this way for free, just had to open a dropbox account.

Pull the hood. Trace the water lines from the pee hole back to the motor (find where the water cooling line is connected to the motor). Remove the water line from the motor. Hook to water hose and crank.

Does it pee? If so, you got a clog somewhere in the water line between the motor and the pee hole.
Pees a little but not sufficient, pees more with throttle? Likely water pump impeller issue.
Doesn't pee at all? Likely a water pump impeller problem.

I took the lower unit off and found that the impeller was melted to the water pump housing and that the water pump housing itself had melted and cracked. I'm assuming exhaust gases over the years must have cause the housing to crack. Not sure really.

Not good. Hopefully, motor didn't get ran hot. Sounds like one of those guys that likes to fire it up in the driveway withwith no water before heading to the ramp.

Any way I can check to see if motor was ran hot? The oil in it looks good. Check compression maybe?

Replaced the impeller, impeller housing and associated gaskets. Also went through the cooling system and removed all the little pieces of impeller that had found their way up. Also removed the thermostat as it was stuck closed. I will renew it before cold weather sets in. I changed out the crankcase oil and the lower unit oil and cleaned the carburetor throughly. The little motor runs like a champ now.