Volvo penta tamd71a overheating problem

[Celik28]

I have a 71a engine. I have been experiencing a temperature problem for a while. Overheating starts after 1500 rpm. The sea water pump was revised, the fresh water pump was renewed, the thermostat and its housing were renewed. An additional mercury temperature gauge was connected. The coolers were cleaned. There is no compressor in the expansion tank. There is no water in the oil or oil in the water. The cylinder heads were checked and there is no leakage. This problem started with the antifreeze becoming muddy. The entire system was cleaned but it did not improve. The above procedures were performed in order and I did not get any results. The only thing that remained unchanged in the fresh water system was the oil cooler. In the last tests, I noticed that the crankcase was hotter than the other parts of the engine while it was rising to the temperature. I am using this engine on a fishing boat. It has strained my financial and moral means

 

[PlanB]

I sent you a pm a couple of weeks ago.

 

[sharpness]

Check the exhaust elbow cooling jacket isn’t blocked.

 

[Celik28]

Check the exhaust elbow cooling jacket isn’t blocked.

I checked the exhaust is clean

 

[Celik28]

I sent you a pm a couple of weeks ago.

Yes, you told me that you did not remember the failure you experienced in the past.

 

[Celik28]

I removed the oil cooler today. I rinsed it with chemical product and saw some rust and sludge inside. But I don't think it will affect it that much.

 

[PlanB]

No, What I wrote was a list of all the things we did which did not fix the problem, provided a link to a thread on here which had a lot more detail and suggested you start your own thread on here.

 

[Celik28]

No, What I wrote was a list of all the things we did which did not fix the problem, provided a link to a thread on here which had a lot more detail and suggested you start your own thread on here.

We tried everything that the services and masters suggested, but there was no result. When I talked to the masters, they said that you have done everything that can be done, but we think the problem is too small, so you can't find it. There is no one who has said that it will definitely happen because of this or that reason. Everyone is talking about trial and error methods. We are proceeding on the basis of probability.