I just finish putting my full close cooling for a 350. Seems to have no leaks and seems to work. Im getting the water through the exhaust. My question is this:

I ran it and the temp barely hit 160. But for the 10 min I ran the boat the manifold where hot, can only touch then for 3 seconds before it burns, the thermostat housing (its a T now) was hot. The cooler was warm (seemed like the bottom was colder than the top), hoses where hot and what not. Is it normal for it all to be hot like this, esp the manifolds? It seemed to be a steady hot, the temp barely got to 160. It was quickly too. I got kind of worried. I ran it twice, first for 10 min shut it down for a few and started again for 7 min. Same thing both times.

Before when I ran this it didn't get so hot so quickly. Why is this getting hot so quickly and with it being hot is it ok? Any help or opinion is a great help!

the manifolds shouldnt get that hot my 350 with a san jaun kit never does. what kind of kit did you use? did it come with a new thermastat? do you have a sea water pump like a bravo or is this on an alpha

Its a san jaun MC314. It came with a 160 thermostat. Its a alpha with the pump coming from there. The hose that goes from the heat exchanger to the water pump is cold. The hose that goes to the risers are cool. the bottom of the exchanger is cold while top is warm. hose from the bottom of the manifold to the T housing is hot. manifolds are hot, hose from the top of manifolds to the cooler is warm. Any suggestions??????

I don't know much about closed cooling but why not try without thermostat? Isnt the raw water pump set up to go straight to manifolds? What else does it cool. Oil?

It's a full system so antifreeze water circulates from the heat exchange to the water pump to the block. Then when the temp uisnt at 160 it won't go to the manifold and goes back to the water pump. But if it is at 160 it rubs through the manifold

The person you bought it from should help you. But there is at least one thing that is not right in your post. The sea water leaving the heat exchanger should have a raised temp. That water has theoretically cooled the glycol and therefore should have an elevated temp noticeable to the touch. It's last job is to cool the risers before entering the sea with the exhaust. It should not be cool.

If you want to call I'll try to help even though we didn't sell you this kit. But make sure your hose routing matches the diagrams sent first. My guess is you'll find the problem in your hose routing. The kits are pretty robust.

Russ