2000 Catalina 36 MkII. I replaced my Seaward 6 gallon water heater with an Isotemp SPA 20. I was a bit worried that it would fit without moving the water pump. It did fit without moving the pump or any other components. I used all new 5/8" hose from the engine to the water heater (1) 15' and (1) 14'. I filled the hoses and heater with 1.6L coolant before connecting them to the engine.
Another note is that when the coolant hoses were removed I found a spot one one hose almost worn through. I figured out the hose was rubbing on the prop shaft coupling where they pass under the engine. I feel lucky that I did not choose to just add (with a couple barb fittings) the necessary hose to reach the new water heater.
We installed the SPA 15! Great water heater!
Robert Clyde
Charles, thanks for sharing your experience, it is a clean job. Do you have the height from the wood platform where the heater is strapped up to the bottom of the icebox? Does the water heater have magnesium anode?
Also, I noticed that your macerator is connected directly to the PVC "T" splitter that is connected to the holding tank. In my case, the macerator impeller housing broke and separated from the pump and the unspeakable drained into the bilge from the holding tank. I placed a 2 way valve after holding tank to direct holding tank to pump out hose or to macerator and I placed 4" hose between each connection to provide flexibility. For images see my signature website and album.
Sail La Vie 1999 Catalina 36 MKII, M35B-17031, Coyote Point, San Mateo, CA
About Sail La Vie
Hi Haro, There is 13.5" from the wood platform to the bottom of the icebox box. It does not have an anode. I too, had the same issue with the pump. When replacing it I checked and had drilled new screw pilot holes to make sure there was no stress / load on the pump or fittings. The pump and water heater have been replaced both in the last couple weeks.
Nice job on you new pump mounting!