VP AQ260A Workshop Manual? Over heating Issue

[clintcjc]

Anybody have a VP AQ260A (GM SBC 350, 5.7L) workshop manual? I have been chasing an overheating issue (up to 200 degrees F at cruising speed). Replaced the impeller, thermostat, exhaust manifolds and risers. Doesn’t seem like enough water is being circulated through the engine cooling system and out the stern drive. I’m looking at replacing the seawater pump/housing or maybe the heat exchanger next. Any advice welcome.

 

[emac]

I've got the 380 ,and have been chasing an overheating issue too. Mechanic is saying theres an air lock, preventing the coolant from circulating. A bad overflow cap can disrupt the pressure needed to fully circulate the coolant. I had no problems first 3 years, ran at 165 all day long. Is your engine raw water cooled or fresh water cooled? My problem has yet to be resolved as well.