So last year a few of you know I had some trouble wirh one of my manifolds that melted down.

anyways finally back to working on this thing after many set backs.

I’ve always wondered cause on everyone else’s boat I only ever see 1 line coming off the t stat housing and going to the manifold. On mine there is another “ T” ( pictured ) and it’s also going to the manifold. So both ports on the bottom are plumbed in. What gives? Is it needed? Or is one cool? It sure would make the front of my engines a little less cluttered.

side note: I did not to this originally I just went back to the way they where but curious if I will gain or lose here? And how to do this correctly do I use the front port on the bottom or the back port if I go with one line…? Thank you!

Cig, likely it's a thermostat setup to provide water flow to the exh manifolds while the thermostat is closed. Once opened, it will have 2 flow ports feeding the exh manifolds.

Closed coolibg work in a similar way....for full cooling systems where the engine coolant cools the exh manifolds. They need flow while the thermostat is closed.. I that case...the thetmostat needs to be located at the heat exchanger. It probably gets the engine warmed up a lot quicker.

The later style t stat housing like found on 502mpi’s and etc only have 2 outlet hoses. They work quite well.

Your current style was found on the HP500’s snd some others

You could clean the front of your motor up a ton by eliminating the circulating pump and just running a crossover.

The said “T” has these in it as well. Both sides

yes those are check balls to keep the water from returning to the housing..........one way out

hey man! What are the chances of those going bad so to speak? They seem to be pretty stiff honestly.

Ive never heard of them going bad but always a first time, you should be able to pull them out with two fingers then let go and the should return quickly