Bypass Hose Function

Exactly what is the function of the coolant bypass hose from stat to pump? Installed new one in place of long piece of crimped heater hose po had on.

 

It bypasses the thermostat should it stick in the closed position. You want it.

Having the correct one is a good thing.

A lot of people do what the PO did.

 

It also gives you a little heat before the thermostat opens.

 

and will help to purge air from system when first filling on antifreeze change

 

It makes the coolant circulate while the engine is warming up or else it would overheat prematurely.

Tom T.

 

Exactly. If the coolant was stagnant the thermostat would rely on radiant heat to open. Meanwhile the coolant above the chambers would be boiling..

 

Bypass the thermostat. For circulation.

 

What Joe said. It moves warm water across the thermostat spring so the T'stat knows when to open. The water near the spring would take forever to warm-up without the by-pass hose.