High Temp

[B_loc1]

Just launched our 1993 Malibu EuroF3 today for the summer. Ran it around the lake a few times and when I slowed back down near the dock the high temp light was on. So I took one more lap with my eye on the temp gauge and when I was going fast the temp lowered between 120 and 160 and the light was still on. When I slowed down again as well as in idle, the temp began to rise. Im assuming it's the impellar, but we replaced the impellar and thermostat last year. Could it be anything else? I am 100% sure that it was never dry started. Last time the impellar was bad a the high temp light was on and an alarm sounded. No alarm this time. Any help would be appreciated. Thanks

Brian

[shade]

It sounds like one or a few vanes may have sheared off the impeller. Saw the same thing happen w/ a friends SAN. The temp would rise at idle and go down at cruising speed (more water circulating through the engine). Sure enough, 2 vanes missing from the impeller.

[smaj]

I would agree. Sounds like there is a problem with the impeller. Even if it was new last season, it could have gotten a piece of debris inside and that could have torn some of the vanes off. Good luck.

[B_loc1]

Thanks guys, I will open it up tonight and report back.

[skier92]

Remove the hose between the raw water pump and the trans oil cooler and flush it out. Debris will lay in the low point of the hose when water not flowing and push up against cooler when water is flowing. While the hose is out, check the trans cooler for debris. Pull the impeller and inspect. Check the inlet and outlet ports of the pump for debris. Back flush the water pickup hose.

[B_loc1]

Pulled the impeller and at least a part of all 8 vanes were sheared off. 6 of the 8 pieces were still in the housing. Replaced the impeller. Now I will check for debris in the system, just not exactly sure what hoses to flush. Thanks again for the responses.

[skier92]

Disconnect hose from bottom of boat from raw water pump. This is the inlet hose. Run water from garden hose into pump end of inlet hose to flush it out. Take the other hose that connects to the pump completely out of the boat and flush it out, check both ports on pump for debris, check bottom of trasns cooler for debris, then re-install both hoses)