I just updated my 79 Scarab 300 from log style manifolds to center rise with merc captains call. My motors are 330/TRS my motors never ran warm on the water around 100 one motor had a t stat the other one didn't (don't ask me) thats the way it was when I bought it. I hooked up my sea water pump to my garden hose started the one motor ran it a little while temp went up to 160-180 with out a t stat, just checking things out leaks and all before putting on the water. Any ideas way it would run that warm? All the hoses feel cool/cold risers/manifolds the same, circ pump stat housing intake warm/hot. Any help would be great. Thanks

Probably not enough water flow through the hose. Put it in the lake. I would also run 140* T stats in them.

How long did you let it warm up, mine on a hose takes forever and have little pressure thanks to well water. if it warmed up fast i would think you may have some issue.

I'd keep an eye on it and def run a T stat.

Thanks guys figured out what the problem was. I'm using my old t-stat housings (from the log style manifolds) until I find the ones that I need. Had to block off 2 of the outlets, I blocked off the wrong ones so the water was not circulating through the whole system. The old log manifold style t-stat housings have 6 small outlets, the center rise style t-stat housings have 4 small outlets