1992 Evinrude 40hp overheating

Psychodad7

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Jun 3, 2009
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I just bought a boat with a 1992 Evinrude 40 hp motor. It would not pump water through the telltale with the muffs, so I replaced the waterpump parts12 pc. kit. same result. Put motor in 1/2 barrel of water, Have water coming from the telltale for about 10 seconds then it stops for about the same amount of time, repeats until alarm sounded continous. Shut down let cool to 120 removed thermostat and restarted, same results. Rpm's did not appear to have any affect, also smokes a little from telltale until water flows when first started. Where should I look from here?
 

tashasdaddy

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Re: 1992 Evinrude 40hp overheating

check your compression, sounds like a blown head gasket, the leaking compression into the cooling system is keeping water from reaching the head.
 

Psychodad7

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Re: 1992 Evinrude 40hp overheating

Compression cold 135 psi, lower cyl will bleed down about 5 psi in 45 seconds. hot compression 125, no bleed down after 1 min.
 

HybridMX6

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Oct 22, 2008
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Re: 1992 Evinrude 40hp overheating

Make sure the water pump tube got properly inserted into the tube in the midsection. There's also supposed to be a rubber grommet or something where they meet I think. Mine doesn't have one, not even on the parts diagrams ('93 60hp 3cyl).
And it's a dumb question, but you did put the impeller key in and also installed the impeller the correct direction?
 

tashasdaddy

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Re: 1992 Evinrude 40hp overheating

99% of the time the impeller will right itself, if installed backwards.
 

HybridMX6

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Re: 1992 Evinrude 40hp overheating

99% of the time the impeller will right itself, if installed backwards.

Really? Never knew that. Good thing to know I guess, should I ever doubt myself AFTER I've installed the lower.
 

Psychodad7

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Re: 1992 Evinrude 40hp overheating

I installed water pump the same as the one I took out, Not to say it was correct. Kit came with o-rings and seals,ring and housing. I have a manual on the way. But the parts diagram I seen online looks like the radiased wedge key is in the other way. and then the pump vane would need to be flipped. When I run it, it will cycle, pump-no pump 6 or seven times before the alarm will sound. 6 to 8 minutes of run time. Pumps and temp will drop some, quits pumping and temps will rise, then pump again, gradually overheats. Is it possible when it heats the leak will seal and as it cools leak will open, perhaps in the mid section of the motor exhaust water tube area?
 

Psychodad7

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Re: 1992 Evinrude 40hp overheating

Update. Gasket under Powerhead was bad. Pee's like a kid again.
Thanks
 
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