Evinrude 140 Overheating?

[Hardcore]

'92 evinrude 140 looper. runs for awhile and then spark quits. took it to my mechanic and he thinks it is overheating and says one head is running much hotter than the other. he says there is a temp switch that will shut off the ignition when it overheats. i thought it just had the SLOW function. he confirmed with a temp guage but is there actually a switch in there that performs as such? i am afraid there may be an overheat and a separate ignition malfunction.

originally would run for 10 minutes and die, have to cool down then run again but i took it out another day and it idled for about a minute and spark quit. so i am confused.

of course, it runs fine when the mechanic runs it???

 

[jonesg]

Re: Evinrude 140 Overheating?

He's right, as I understand it..
the temp sensor isn't the switch, it signals the power pack and theres a solid state switch or software in the pack that shuts down one bank.
That would be the SLOW mode.

So it looks like a thermostat change, pressure relief valve, backflush( I think) , some might recommend pulling that head and checking the water diverters, either way I would install a temp guage, the head is pre-tapped for it, they're a convenient way to monitor head temps on the fly.
If you get 2 temp sending units you can use a 3 way switch and just use one guage.