dearly
New Member
- Aug 15, 2017
- 4
- Boat Info
- 1999 Sundancer 240
- Engines
- 5.0 Mercruiser with Alpha One Gen 2
Hello and thanks for reading my post. I've spent years reading but have never posted before. Hopefully in the future I can help others as this site has helped me in the past. However, I really need some help here.
I cannot seem to find anyone with this issue. I'm in Clearwater, Florida (Salt) and run my boat all year long. It's in a slip (not on a lift) but I flush it out after ever use. Gear is 5.0 Mercruiser (Non-EFI) with Alpha One Gen 2 Drive, Raw water cooled. A few months ago it started to overheat under load at high RPM. I used a IR Thermometer and found the manifolds and elbows were getting warm. I replaced the manifolds, risers, elbows, water pump housing and impeller and thermostat (160 degree).
Now here's the problem: When under load and higher RPM's (2,500 +) out of nowhere the temp gauge will suddenly drop down to 100 degrees and then climb back to 170 degress (Normal temp reading for this sender). If I don't back down on the throttle to 2,000 RPM's or less the temp will climb until the alarm sounds. If it sounds I back off and idle for a few minutes and it cools down again. Sometime I can run for an hour at high RPM and Load without the problem showing up. But it's happening more and more lately.
Any ideas? I sure would appreciate any input you might have. Thanks in advance!
I cannot seem to find anyone with this issue. I'm in Clearwater, Florida (Salt) and run my boat all year long. It's in a slip (not on a lift) but I flush it out after ever use. Gear is 5.0 Mercruiser (Non-EFI) with Alpha One Gen 2 Drive, Raw water cooled. A few months ago it started to overheat under load at high RPM. I used a IR Thermometer and found the manifolds and elbows were getting warm. I replaced the manifolds, risers, elbows, water pump housing and impeller and thermostat (160 degree).
Now here's the problem: When under load and higher RPM's (2,500 +) out of nowhere the temp gauge will suddenly drop down to 100 degrees and then climb back to 170 degress (Normal temp reading for this sender). If I don't back down on the throttle to 2,000 RPM's or less the temp will climb until the alarm sounds. If it sounds I back off and idle for a few minutes and it cools down again. Sometime I can run for an hour at high RPM and Load without the problem showing up. But it's happening more and more lately.
Any ideas? I sure would appreciate any input you might have. Thanks in advance!
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