Need advice, engine overheated after repair

[markwjones]

Took my i/o mercruiser in for steering problem and tune up. Mechanic also replaced impeller without my consent. Boat running fine prior to taking to shop. Put boat in water after repair and immediately ran hot. Took back to shop. Repair shop called later to tell me engine ran hot because thermostat had locked up. Please advise: Is it likely the mechanic did something wrong when replacing impeller and that is what really caused the problem rather than thermostat locking up? Thanks for any input.

 

[Don S]

Re: Need advice, engine overheated after repair

It's possible. Without being there to actually see what was wrong, there is no way of possibly knowing what the problem was.

What engine, what drive, what year, what type cooling system?

 

[markwjones]

Re: Need advice, engine overheated after repair

Thanks for responding. 135hp, v6. 1998 model. Mercruiser outdrive. Don't know how to define type of cooling system but it has a water pump on front of engine like typical auto engine and thermostat housing on top. Is the impeller replacement easy to get wrong?

 

[Moku'ula]

Re: Need advice, engine overheated after repair

I've heard of people on here mixing up the intake and outflow hoses on the water pump housing and having the engine overheat...

Mine are marked with a B and a T for bottom and top...

Jef
Moku'Ula
1999 Four Winns Horizon 180

 

[CharlieB]

Re: Need advice, engine overheated after repair

Immediately request old parts.

Take the T-stat home and test it's opening temp in a pan of water on the stove. It is possible that it failed.

If the mechanic failed to ensure the key was in place on the impeller, it didn't turn to pump any water and the motor would immediately overheat.

If this happened, He should have seen this when he test ran the motor.

IF, the key was NOT in place and the shop has since replace it, the impeller would have marks inside the sleeve made by the spinning shaft.

If the shop has replaced the impeller again there would be no evidence.

Tough call.

 

[JustJason]

Re: Need advice, engine overheated after repair

I can't imagine the shop didn't float test the boat after the tune up. At bare minimum they shoulda backed the trailer down the ramp and let the boat warm up before they set the in gear idle rpms....

 

[Don S]

Re: Need advice, engine overheated after repair

I can't imagine the shop didn't float test the boat after the tune up. At bare minimum they shoulda backed the trailer down the ramp and let the boat warm up before they set the in gear idle rpms....

Kind of hard to do if the shop isn't close to any ramps.

 

[Bry21317]

Re: Need advice, engine overheated after repair

I had this same type of problem last year. I had a mechanic replace the Impeller, and it started to overheat on my 94 Alpha 1 Gen 2 drive. I then had to do it 2 more times, taking the pump/housing apart and redoing it. Still leaked and still over heated. So finally I purchased the entire Housing Kit again, and found that the bolts holding the housing down, were tightened to tight and thats where it was leaking. Finally got it all perfect and to I think, 15lbs/ft for the 4 bolts that hold the housing down.

No problems after that. Maybe this will help you.

Bryan

 

[fat fanny]

Re: Need advice, engine overheated after repair

To chime in on Don S last post. How do shops verify this above posted type work if they are not close to a body of water? Also I live in northeast Ohio and all but 1 shop isn't w/in 5 miles from a ramp and or body of water to verify there work under load. Do they use muffs,garbage can or some sort of large tank?. It makes non service qualified? boaters wonder if the techs nowhere near water are just guessing and if they are they must be pretty good at it or you would hear more about service shops integrity here on the forum. There has to be a more logical explanation for a test method than the above mentioned guessing? What about service in the winter months?

 

[Bt Doctur]

Re: Need advice, engine overheated after repair

Or this happened