496 HO overheating today
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Any suggestions? Took out boat ('02 Nordic) Heat today, started it off the trailer and heard a sound like a belt screech. Sat at idle waiting for friend when alarm came on. Checked gauges, nothing out of ordinary, shut down and raised hatch. Belt o.k. etc. Turned back on, alarm still sounding. Temp. at 180, shut down again; checked engine- starting to smoke off exhaust man. smelled like burnt rubber. Pushed back on trailer. At idle off trailer boat sounded louder than usual. Almost like it wasnt circ. any water. Checked water pick ups -clear. Impeller?? Waterpump?? What do you guys think??
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98% chance its the impellor.
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Originally Posted by Nordic D
Any suggestions? Took out boat ('02 Nordic) Heat today, started it off the trailer and heard a sound like a belt screech. Sat at idle waiting for friend when alarm came on. Checked gauges, nothing out of ordinary, shut down and raised hatch. Belt o.k. etc. Turned back on, alarm still sounding. Temp. at 180, shut down again; checked engine- starting to smoke off exhaust man. smelled like burnt rubber. Pushed back on trailer. At idle off trailer boat sounded louder than usual. Almost like it wasnt circ. any water. Checked water pick ups -clear. Impeller?? Waterpump?? What do you guys think??
It is very important-especially on the Bravo/496's-not to run the pump dry. The impeller is very easily damaged. Installing a flush kit would cause the water to enter on the outlet side of the raw-water pump which would probably damage it and would not flush the drive passages. Did you recently use a flush kit? This is one instance I was told where the Mercury Flusher works much better for that reason. Off brand flushers on Bravo's have caused many impellers to fry.
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We have also seen where if the engine doesn't start right away and spins back-wards for a second, it actually folds the impeller blades back-wards and stops the pump from turning forward. Easiest way to check this is to take the belt off and see if you can turn the pulley by hand in engine rotation.
If you can turn it in engine rotation, its like others said, probably a bad impeller. As for the alarm going off and gauges looking OK, the high exhaust temp and no water pressure will sound an alarm and you wont see it on the gauges until the engine temp gets to high.
Pwrbt33
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If you can turn it in engine rotation, its like others said, probably a bad impeller. As for the alarm going off and gauges looking OK, the high exhaust temp and no water pressure will sound an alarm and you wont see it on the gauges until the engine temp gets to high.
Pwrbt33
Offshore Performance
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410-827-0200
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