what is the Fresh Water Bipass used for?

[21270]

I'm going over the full fresh water system instructions for my merc 4.3. They say to install a 5/8 tube from water pump to pipe plug in intake manifold. If i'm not running a heater, do I need this?

 

[Bondo]

Re: what is the Fresh Water Bipass used for?

Are you installing a New Kit ?? Or just reading over on what you already have ??<br /><br />I'm Quite Certain that if it's a New system,+ You see there'll Never be a use for a heater circuit,....<br />You can just leave the Plugs in those 2 ports.....

 

[21270]

Re: what is the Fresh Water Bipass used for?

Bondo, I'm installing a new kit and wasn't sure if that was needed or if I could just leave those plugs in.

 

[rodbolt]

Re: what is the Fresh Water Bipass used for?

hello<br /> its to allow water to bypass the t-stat to allow hot water to actually make it to the t-stat before the water in the heads boil. use it.<br /> it will make a difference. has nothing to do with any heaters. that is a different tap.<br /> otherwise the water just sits at the t-stat waiting for the block and heads to get hot enough to heat the water so the t-stat will open. its possible that the heads will get hot spots and steam pockets long before that happens.

 

[21270]

Re: what is the Fresh Water Bipass used for?

Rodbolt, thank you!

 

[Bondo]

Re: what is the Fresh Water Bipass used for?

Well,........ There you Go......... I learned Something Too......

 

[Buttanic]

Re: what is the Fresh Water Bipass used for?

There is usually a bypass passage around the thermostat to allow coolant to circulate through the exhaust manifolds before the thermostat opens so why would the hose be necessary. the flow to the manifolds would bring heat to the thermostat

 

[rodbolt]

Re: what is the Fresh Water Bipass used for?

buttanic<br /> on some models of fresh water cooling. not all. if it was a factory set up AND had fresh water cooled manifolds maybe. but a lot of kits are half system kits and the miniufolds are raw water cooled. just depends on who made the kit and the manifold design.<br /> and its odd that for some reason most v6 motors only get a half kit. were it mine I would buy the full closed cooling kit and toss the risers every 3 years, but its not.

 

[21270]

Re: what is the Fresh Water Bipass used for?

The one I'm installing is a full system, I will be doing what rodbolt said, toss the risers every 3 to 4 years!

 

[rodbolt]

Re: what is the Fresh Water Bipass used for?

some full systems run the coolant from the tstat housing through the manifold and back to the heat exchanger and some run it the opposite way. depends on who designed the system. best to follow the instructions with your kit.

 

[21270]

Re: what is the Fresh Water Bipass used for?

Rodbolt, I'm piecing one together and finally have all the pieces to put it together. The instructions are from the internet, off the i-netmarine site for a 4.3 full system, I think it's from the Saun juan system?