I recently posted this on another thread before I found the Cal 31 thread. I would appreciate any comparison data other Cal 31 owners are able to provide:
I have a Universal 5416 installed in my 1980 Cal 31 and am evaluating my cooling system for proper performance. I have the performance specs for my particular raw water pump, but would like to conduct an informal survey of Cal31 owners with Universal 5416 (M-20) power for which raw water pump people are using and what amount of total raw water system throughput they are seeing.
My measurements, taken from a bucket on on a line collecting water from the exhaust, are as follows:
Engine: Universal 5416
Raw Water Pump: Moyer Marine MMI 502
Raw Water Throughput at 1,800 engine RPMs: 7.5 quarts per minute
Raw Water Throughput at 2,000 engine RPMs: 8 quarts (2 gallons) per minute
After removing, cleaning and reinstalling the heat exchanger and replacing all raw water lines, I am now up to 11-12 quarts (3 gallons) per minute @ 2,000 engine RPM. Given that the 5416 has a camshaft mounted raw water pump, that means the pump speed is half the engine RPM, so total system throughput is close to the rated pump specs of 3.5 gallons per minute @ 1,000 pump RPMs.
Last edited by Groven; 09-25-2009 at 10:22 AM.