1990 Yamaha 40 overheating? Damage?

[56 crestliner]

I inherited a 1990 yamaha 40. The engine had no electrical power. After a lengthy diagnosis, I got the engine to fire up. It ran well for a few minutes then the overheating alarm on my throttle control went off. I had no idea what the noise was or where it was coming from. It took me 3 minutes to find the alarm, and during this time the engine was still running. I turned the engine off and researched the problem and guessed that I wasn't getting any water to cool the engine. Sure enough, there wasn't any water coming from the tell tale pee hole on the outboard. I figure I need a new impeller/cooling system. My question is whether it is likely or not I did any damage to the engine running it without adequate water to cool.

 

[Yamajoe]

Re: 1990 Yamaha 40 overheating? Damage?

Possibly, but you should change your water pump and thermostat; lower unit oil, do a compression test and post your numbers, as a start.