30L GS Overheating

"I have a 3.0L Volvo GS 1997 r

"I have a 3.0L Volvo GS 1997 rebuilt engine that is constantly overheating no matter what we do can't seem to get it fixed. The engine has always gone to 175, but never over. It now heats up to 175,and then goes to 225, We have replaced the impeller, thermostat, and water pump, and even cleand out all the impeller parts through out the engine. It is fine when running at low speeds but as soon as the throttle is pushed down it heats up. I am the original owner of the boat, the engine was rebuilt in 2004. Any info would be greatly appreciated"

"If it was run hot due to a br

"If it was run hot due to a broken impeller, You may have to check that the seals for the water tube in the drive have not been burned making the pump suck air when planning. This may happend if exhaust and no water passes out through the drive."

"Actually the impeller was rep

"Actually the impeller was replaced two years ago, I changed the impeller this time just because i had it out to check it, but nothing wrong with the old one. I have not been able to use the boat, once the engine heats up I shut it down."

"I have the same problems, som

"I have the same problems, some time mine does it and other times it dont, i have to watch my temp gauge and check the motor constantly. did you ever resovle anything with yours?"