Water lines to headers on a 454. How to hook them up?

[21 Hawaiian]

Yo Guys. I have a 21 foot Hawaiian jet boat. Engine is a Chevy 454.Jet drive is a Panther. On the water lines that go to the headers there are 2 hose hook ups on the front of them. And 1 water line hook up on the rear.Each header has 3 water lines to it. Anyone have a link ,or photos of how to hook these water lines up to the engine? Thanks. Mike S. Westville,N.J.

[woodboat]

Raw or fresh water cooled?
two connections will complete a cooling circuit the third one is a final discharge of raw water.

[21 Hawaiian]

Thanks for the reply. Fresh water cooled. So the rear header hook ups are not used?

[woodboat]

Most boats run a wet exhaust even if they are fresh water cooled. If you are running a wet exhaust use this as the dumping spot.

[21 Hawaiian]

On my other jet boat I had. It used Bassett wet headers. Over the transom.The water was injected into them,and out the back. These headers are thru the hull. So your saying the water will go out the headers.And I should run a hose on the hook ups from the back of the headers to? I'm getting confused. Sorry. Each header has 3 water connections. 6 in all.

[jman]

test 1234

[jman]

454 headers hook up- water coming in should "T" than both lines should go to bottom back of headers (cooling chamber) than will come out the front of headers lines will go to thermo housing area. Should be 4 port housing 2 lines under theremo and 2 on top. The ones on bottom should connect to fron bottom headers and the top 2 ports should connect to top exhast headers. Thats it!

If it starts getting hot than you have it hooked up wrong or you have bad or incorrect thermo. If it ran before with the same thermo your probably fine. Watch out for rebuilders they will screw you up for a while... my boat is now losing power but the overheat and headers are fixed!!

[jman]

By the way I bypassed my thermo all together and runs really cool. just connect the two top port together and reverse one of the exaust and thermo hoses. thats another way.

If you can help with 454 underpower I have would be greatly appreciated.

should be running 50+ @5500 rpm

only getting 32mph @ 3500 rpm

thanks

[21 Hawaiian]

Thanks for the info. If its a jet drive. You might have something caught inside. I had a 6 pack plastic holder in mine. Just a small thing stuck inside of the jet drive will cause problems.