WELCOME TO RIVER DAVES PLACE

Plumbing Question

aftershock

New Member
Joined
Apr 12, 2021
Messages
3
Reaction score
12
Looking for some opinions/clarity on jet boat plumbing. New to the jet boat world and everything I've searched for online still has me a little confused. I recently purchased a 21 skier with a 6.0 vortec (Kodiak Marine) and a dominator pump. It originally had the water inlet from the pump go directly into a thermostat housing with a 140deg thermostat. The thermostat went bad and wouldn't open anymore so I took it out. Now after reading other threads about plumbing I'm worried that I might be giving the motor too much water pressure without the thermostat. There's no valve or anything like that from the pump to the thermostat housing. Should I put a thermostat back in? Should I leave it out and install a gate valve? Pressure relief valve?
 

Dennis-19

Well-Known Member
Joined
Aug 13, 2018
Messages
1,507
Reaction score
2,898
Looking for some opinions/clarity on jet boat plumbing. New to the jet boat world and everything I've searched for online still has me a little confused. I recently purchased a 21 skier with a 6.0 vortec (Kodiak Marine) and a dominator pump. It originally had the water inlet from the pump go directly into a thermostat housing with a 140deg thermostat. The thermostat went bad and wouldn't open anymore so I took it out. Now after reading other threads about plumbing I'm worried that I might be giving the motor too much water pressure without the thermostat. There's no valve or anything like that from the pump to the thermostat housing. Should I put a thermostat back in? Should I leave it out and install a gate valve? Pressure relief valve?

Don't use a gate valve. Ditch the T stat.
Off pump, into a regulator set at no more than 40psi then into block, dump from thermostat housing. The Watts regulators work well.
 

jetboatperformance

Well-Known Member
Joined
Jan 1, 2008
Messages
3,653
Reaction score
4,621
Looking for some opinions/clarity on jet boat plumbing. New to the jet boat world and everything I've searched for online still has me a little confused. I recently purchased a 21 skier with a 6.0 vortec (Kodiak Marine) and a dominator pump. It originally had the water inlet from the pump go directly into a thermostat housing with a 140deg thermostat. The thermostat went bad and wouldn't open anymore so I took it out. Now after reading other threads about plumbing I'm worried that I might be giving the motor too much water pressure without the thermostat. There's no valve or anything like that from the pump to the thermostat housing. Should I put a thermostat back in? Should I leave it out and install a gate valve? Pressure relief valve?
Loads of questions for clarification call for Tech help 805 466 4719
 

Blackmagic94

Well-Known Member
Joined
Apr 4, 2017
Messages
3,494
Reaction score
4,454
I run this as a dump valve to prevent the pump from over pressurizing the engine coolant passages




At 15 psi it vents excess water through a hull mounted dump

I also have a pre screener filter after this to prevent debris from entering as well.
 

Nikwho

Well-Known Member
Joined
Jan 8, 2019
Messages
216
Reaction score
175
I run this as a dump valve to prevent the pump from over pressurizing the engine coolant passages




At 15 psi it vents excess water through a hull mounted dump

I also have a pre screener filter after this to prevent debris from entering as well.
I run a similar pressure regulator, followed by a wye strainer. They are very easy/quick to clean out.

 
Top