Port main 454 cruisader is running hot
Posted: Mon Apr 19, 2010 11:32 pm
Ok, loaded question, so I know I'll probabaly get a few different answers, which is what I am looking for. I have an '83 10 meter sedan with 454 gas crusaders with heat exchangers. My port main is running hot..... it started out steaming a bit more than the Stbd over the past many months, then a month ago she sounded a temperature alarm and I shut her down. I limped home on one engine and shut her down. I went to start it later that day and it wouldn't start... turns out the starter silenoid went out (coincidence), so I changed it and she fired right up. I have been busy at work so I had someone change both raw water impellers, but both looked great. I then pulled the riser elbow, and it does have some minor corrosion, but overall is wide open and clear. I then changed the thermostat and ran her in the slip (the tide is out too much to run here tonight so I can't get her off the lift beams) and at a fast idle the temps slowly rise and the temop alarm is chirping. I believe the salt water flow is good as it appears to be about the same volume on the port as the Stbd, which leaves me to wonder about the fresh water circulation or internal blockage. Does anyuone know how much GPM i should be getting on the raw water side? should I pull the heat exchanger and have it acid dipped? Where would you start?