Volvo Penta 4.3 GL-D Overheating

[Cdusza]

This engine has been sitting since 07 and only has about 10 hours on it. I pump out the old gas, replaced the battery, raw water intake impellar, and thermostat. The oil looks fine. I also pumped water through the thermostat block opening through the engine and out the circulation pump hose. There does not appear to be any blocks. I did not replace the thermostat o ring but the old one is in good shape. What could be causing
the overheating?

 

[jackm137]

Re: Volvo Penta 4.3 GL-D Overheating

I have had the same problem 3 years ago with the 4.3 same motor. First of all the motor was only 3 seasons old when the problem began, second I found out it was a GM motor which helped a lot since I am familiar with there built in obsolescence. What I did is what I used to do with almost all
the cars, I drilled out the thermostat in 6 places with 1/8 drill. Did not work so I took out the thermostat and wow. I have used it for 3 years no
problem. Just so you know I went against many good mechanics who said it would self destruct. No problems. They are inside the box on this one. I
believe the problem is in the outlet manifolds and the port holes that the water travels through. In sea water it seams to corrode in layers. GM has designed that motor for fresh water only-My Opinion. Not sure if I created any problems but try it out in a local spot first. Jack

 

[Don S]

Re: Volvo Penta 4.3 GL-D Overheating

The thermostat is not your problem, if you can't get water to the pump, anything after it means nothing.
I would be looking for air leaks in the pump or hoses between the raw water pump and the outdrive.

Don't start drilling or removing your thermostat. That is not how things are fixed. it's how you make things worse.

 

[Lou C]

Re: Volvo Penta 4.3 GL-D Overheating

volvo has a PDF document, called Volvo Penta Overheat Diagnosis, it tells you how to troubleshoot the cooling system including using clear reinforced hose to look for air leaks. Do a search, its worth looking at and print it out....

 

[Don S]

Re: Volvo Penta 4.3 GL-D Overheating

Good point Lou, I meant to put that link in the above post but forgot it. Here it is.
http://www.4shared.com/file/50572185/e88f1d89/Volvo_Penta_Overheat_Diagnosis.html

 

[Cdusza]

Re: Volvo Penta 4.3 GL-D Overheating

I removed the plug from the top of the circulation pump and with the engine running and the water comes out only about an inch high. I expected to see more pressure. Could the circulation pump be bad? I removed it and it appears to be in good shape but I can not see the impellers. Also, is the temperature sensor the metal plug on the thermostat housing with the electrical connection?

 

[Don S]

Re: Volvo Penta 4.3 GL-D Overheating

I removed the plug from the top of the circulation pump and with the engine running and the water comes out only about an inch high. I expected to see more pressure. Could the circulation pump be bad?

Not the circulation pumps problem, It doesn't make pressure. Probably a bad raw water pump, or an air leak in the system.
Follow the test procedures.