what is the purpose of the #3 water bypass hose...

[JO MAOMA]

i'm totally stumped by this one, why is it there...

 

[Kernal]

IIRC to provide some heat to the Throttle Body, maybe more important in cold weather regions.

 

[JO MAOMA]

that is the number 2 bypass and i get that one. the number three connects the radiator
to the radiator inlet pipe on the block, basically it just parallels the inlet hose...

 

[Kernal]

OK, understand now, I kinda thought to maybe to allow the radiator to self burp?? Of course the bubbles would just come back around to the top again. IDK. Someone will know.

 

[JO MAOMA]

hey i like that theory, i does connect the highest point of the system back to the radiator...









.. i'm going with that, thanks.

 

[Kernal]

Or, maybe the other way around, to allow trapped air to get to the top of the radiator then out the overflow tank?? Might prevent hoses from popping off in an overheat situation?? IDK.

 

[JO MAOMA]

that makes sense, the outlet does that loop under the distributor where most outlet hoses are themselves
are the highest point in the system. i'm going to be using a different radiator and wondered if i had to add
an outlet for the bypass to it...

 

[Kernal]

Why not stick with a Koyo radiator?

 

[JO MAOMA]

this is for a stock full race truck i'm building. the cage work in the front is going to make it easier to go
with a full aluminum race radiator with electric fan than try and fit the shroud and outlets to the cage...

 

[SeanLX]

Yea, I'd have to agree that it vents highest point back to the radiator to let air out while filling.

It also provides a nice little plastic nipple to break off and ruin the radiator while your changing the belts.