I replaced all the hoses on my starboard engine and in the process discovered two thermostats. I'd like to know why, and try to figure out if I might have installed one backwards(I reused the old thermostat). After I replaced all the hoses I refilled the antifreeze and now it seems I'm running hot, even though the temp gauge shows normal. All the coolant hoses were very warm and a couple were so hot I could only touch them for a second or two. The sea water side was ice cold. The bottom of the heat exchanger was cold, the top very hot. The manifolds and risers were hot. So I'm wondering if I installed the forward thermostat backwards or something. The forward thermostat housing didn't really have a "groove" or seat for the thermostat, it just kinda sits there over a hole, you have to be careful installing the top of the housing or you'll disturb the placement of the thermostat. I understand that I can have air in the system, but I know I'm pumping sea water. I have a receipt in the boat showing a FWC exchanger being fabricated and installed about ten years ago. I'm not sure if it used to be RWC and was coverted to FWC or what. Perhaps the forward thermostat was left over from the RWC system... The aft thermostat is one of those big ones and I never removed it. The forward stat is small like the standard automotive size. The engine is about(not sure what year, perhaps as old as 1968) a 1974 International Palmer Ford 351. It's very hard to find info on these engines. There are a couple pics of the same engine in some early 70's correct craft or slick crafts or something like that. All those pics show RWC systems. This motor runs great.. My portside engine is a 2001 Crusader 350, it's and interesting setup to say the least.

Forward housing

What are those "caps" on the bottom of the housing? Think I should replace them? Is there something better I can use? Would that be a good place to plumb in a red dot heater?

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