md40 volvo penta

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rowfly

Member
Joined
Feb 10, 2011
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12
My starbord engine is running 10 to 15 degrees hotter than the port engine. I noticed antifreeze comming out of the coolant overflow tank? Good water flow comming from both exhaust. New raw water impellers.. any one else had this problem and how do you fix it ?* Thanks
 
It sounds like you have a bad head or manifold gasket. Do you have any water in* your oil? If yes, then more than a gasket could be the problem.

How many engine hours and what year?*Did you*check your temperature gauge? Check for exhaust gas*in* your coolant - a good Volvo mechanic can show you how to do this. I'd not run the engine any more until you resolve the issue. Post same question on boatdiesel. - Karl there*is a solid Volvo guy.
 
Usually compression at 250 psi + will win over coolant pressure at 7-12 psi and you will get compression pressure pushed into your cooling system- thus pushing coolant out. I would eliminate the simpler things before chasing this high dollar repair. A faulty thermostat can cause overheating which will push AF out of the cap. I would also confirm the HE is not plugged, even though you have good flow.
 
The engines are 1984 and have 3500 hrs. on them. This has just happened . this engine normally runs at 170 to 175. Haven't checked the trermostats yet nor the caps..I'll do this first. thanks for your responce.
 
Do you have a brown stain where the water leak runs over the header tank and engine? If so the stain is from combustion products in the water and indicates a compression leak such as head gasket or a crack. Bill
 
I will take a look at that, I haven't noticed it. I looks like just green antifreeze.
 
NAPA , for about $15 has a pump that fits on most radiator or marine tank tops instead of the pressure cap..

Really easy to find cooling system leaks , with a cool engine you can crawl around that is pressurized.
 
FF wrote:Really easy to find cooling system leaks , with a cool engine you can crawl around that is pressurized.
******* My mechanic has such a pump and it's been a big help.
 
Hey Yall, I fixed it. Come to find out the overflow tank has a pressure cap on it also. The water was flowing out with hardly any pressure on it. Took the cap off of the port engine filled tanks to proper level fired her up and problem gone. ordered 2 new caps today..($46.00 ) each !!!!!. Well thats how I fixed her. Also installed 2 new caps on the engine coolant tanks. Thanks for all the good info you Guys have given me. Im pretty well up to speed on these Volvo MD40s, so if I can help give me a shout. This is a very good forum. Vaughn (rowfly)
 
How abt. that. I have flown Cessna aircraft for the last 40years..Im a Semi-Retire Pilot and Flight Instuctor..Love the good ol C182
 
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