UNIVERSAL M25 OVERHEATING
Moderator: Jim Walsh
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Mike Davis
- Posts: 88
- Joined: Feb 8th, '05, 10:36
- Location: cd31
UNIVERSAL M25 OVERHEATING
I changed my exhaust riser on my Universal m 25 last week. Yesterday, I sailed and on the way back, the engine starting overheating. When I got back to the dock, I did the following: opened up the nipple on top of the thermostat housing and purged the air, opened up the large cap and topped off engine with antifreeze, 50/50. The impeller is working since it is spitting out water from the exhaust. The fresh water pump is working because antifreeze is flowing. However, I can't understand why I am not getting any hot water coming out of the faucets of my sink. Shouldn't it be hot since the engine is overheating? Does the heat exchanger have a significant thing to do with the engine overheating. If it does, i'll take it out and get is cleaned out. All suggestions are welcomed. Thanks, Mike Davis
Re: UNIVERSAL M25 OVERHEATING
Mike, a possible suggestion. After removing my riser, I had a severe overheating problem and most of the water/
antifreeze mix just disappeared. After removing the riser again, I discovered that I had inadvertently installed
the riser gasket backwards. The engine coolant was going out the exhaust! Ideally, the gasket mounting holes
should be offset to be idiot-proof. My engine is the M-30, but yours may be similar. - Jean
antifreeze mix just disappeared. After removing the riser again, I discovered that I had inadvertently installed
the riser gasket backwards. The engine coolant was going out the exhaust! Ideally, the gasket mounting holes
should be offset to be idiot-proof. My engine is the M-30, but yours may be similar. - Jean
Jean - 1983 CD 33 "Grace" moored in
Padanaram Harbor
Massachusetts
Padanaram Harbor
Massachusetts
Re: UNIVERSAL M25 OVERHEATING
I had a similar problem when I replaced my heat exchanger on my M25.
My problem was an air lock in the system.
The water temp gauge pegged but when I put my finger in the expansion tank that water was ambient.
It took opening the cap by the exhaust manifold and also had to rev the engine up and down to get the pump primed and water flowing.
You say the coolant is flowing. Can you see/feel flow in the expansion tank?
Another possible cause could be a stuck thermostat.
Just suggestions.
My problem was an air lock in the system.
The water temp gauge pegged but when I put my finger in the expansion tank that water was ambient.
It took opening the cap by the exhaust manifold and also had to rev the engine up and down to get the pump primed and water flowing.
You say the coolant is flowing. Can you see/feel flow in the expansion tank?
Another possible cause could be a stuck thermostat.
Just suggestions.
Capt Hook
s/v Kumbaya
Cape Dory 31, Hull No. 73
New Orleans, LA
s/v Kumbaya
Cape Dory 31, Hull No. 73
New Orleans, LA
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M. R. Bober
- Posts: 1122
- Joined: Feb 6th, '05, 08:59
- Location: CARETAKER CD28 Flybridge Trawler
Re: UNIVERSAL M25 OVERHEATING
Is any water coming out of the hot faucet? If not check the shutoff valve to the water heater. If you are getting water but it's cool then I would check for the air lock in the cooling system. You may need to purge the system more than once.
Good luck.
Mitchell Bober
Sunny Lancaster, (Where cool is a way of life.) VA
Good luck.
Mitchell Bober
Sunny Lancaster, (Where cool is a way of life.) VA
CDSOA Founding Member