2002 Volvo 8.1 gi, overheating.everything has been swaped with new.

[hall832]

Hello
I am working on a Volvo 8.1 gi closed cooling system. It will get up to 200+/- degrees. The owner had a new circ pump, thermostat, raw water impeller,manifold and risers and still over heating. Flush all system, heat exchanger has good flow. Manifold and risers stay cool while closed cooling gets really hot. The techs that did all this gave up. The only thing I can think of is blockage in the block or heads. Annum suggestions would help

 

[Don S]

Re: 2002 Volvo 8.1 gi, overheating.everything has been swaped with new.

How long does it take to overheat? Does it overheat in the water or on muffs? Do you have good flow of water from the raw water pump?
Does it overheat in neutral or under load?
Has the temp gauge been verified to make sure it's reading right? At 200, the alarm should sound, does it?
Was the heat exchanger original to the boat when it was new, or is it a new addition?
Was both sides of the heat exchanger checked for flow?

What's the full model number, the letter/s after the 8.1Gi, that's the important ones. Or the engine serial number.

 

[hall832]

Re: 2002 Volvo 8.1 gi, overheating.everything has been swaped with new.

1. It overheats around the 9-10 min mark.
2. It Is in the water.
3. yes excellent flow from raw water pump.
4. overheats just sitting at the dock not in gear.
5. Using temp gun. no alarm.
6. Yes the heat exchanger original to the boat.
7. Yes, both sides were checked good water, plus they are relatively cool to touch.
8. can read any numbers on the motor. I know its a 2002 regal w/twin Volvo 8.1 GI With closed cooling.

 

[Don S]

Re: 2002 Volvo 8.1 gi, overheating.everything has been swaped with new.

Try this.

View attachment VP Overheat Diagnosis 1.pdf

 

[hall832]

Re: 2002 Volvo 8.1 gi, overheating.everything has been swaped with new.

Don

i did all of these steps yesterday. couldn't find anything.

 

[Don S]

Re: 2002 Volvo 8.1 gi, overheating.everything has been swaped with new.

Thermostat in the right place and the right direction?