Disappearing water from overflow tank

[wunderluster]

My friend has a Catalina 30 with a Universal diesel. It has an overflow tank in the port cockpit locker. The tank has a hose going to the engine BUT also a hose going to the water heater.

Water seems to go out of the overflow quickly. I haven't found any leaks in the hose to the engine or any hose on the engine. I can't find out why there is a hose going to the water heater. I suspect that is where the water is going. The hose is teed into one of the 2 hoses on the tank. I don't know if it is the inlet or outlet hose that's its tied to.

Has anyone seen a water heater plumbed this way? I'm considering blocking off the hose to see if it makes a difference. We're moving the boat on Monday about 20 miles and I'm concerned with overheating.

David

[Matt Johnson]

Does the tank have typical coolant pressure cap on it? Is the water heater higher than the engine? If so, it is a coolant fill tank and used as a high point in the coolant line to fill from since you can't use the engines fill point. (It's lower than the water heater)

Matt

[wunderluster]

Originally Posted by funjohnson

Does the tank have typical coolant pressure cap on it? Is the water heater higher than the engine? If so, it is a coolant fill tank and used as a high point in the coolant line to fill from since you can't use the engines fill point. (It's lower than the water heater)

Matt

It has a snap on cap. The water heater is lower than the engine, it is about 18 inches below the overflow tank. The overflow tank is higher than the engine. I'm not sure that the water heateris higher than the engine.

I still don't know the purpose of the hose from the overflow tank to the water heater. Maybe it is a pressure relief for the heater?