Check for loose hose clamps on the suction side. Check impeller carefully.
Sometimes the rubber loses bond to the hub. Pull at the rubber to see if it
is bonded to the hub. The seal in the pump behind the impeller could be bad.
The pump cover could be worn enough to cause an air leak.
Jim
"saltare" wrote in message
y.com...
I have an 85 Supra Saltare witha PCM 454 Chevy inboard engine that is
overheating as soon as it gets revved over idle speed. I have replaced
impeller, thermostat, and water pump with no change. I know the hose is
clear from the impeller to the water intake under the boat, because I ran
water from the impeller down to the water intake, but it doesn't appear to
be taking the water in up to the impeller. I checked this by unhooking
the
hose from the impeller to the thermostate housing and its not getting any
water. I know the impeller is turning i.e. turning gear operates
correctly
and belt is not slipping. I am at wits end. Does anyone have any ideas?


Thanks

Saltare