4.6 bypass hose

[Seight-V8]

hiya all,

on the 4.6 engine what is the bypass hose for and could i remove it.

The bypass hose is the small hose that comes from the front of the manifold just under and next to the top hose manifold exit, it then goes down the connect with one of the hoses on the thermostat housing.

As my engine will be in a westfield, i am thinking that i wont need this hose, but what problems might it cause.

cheers

scott

[Ian Anderson]

The Bypass will let water through the heads before the thermostat starts opening.

By sealing the bypass you could get hot spots in the heads as there is no fluid movement till the stat opens

I would think that by sealing the bypass you would then need to have some other way of ensuring the water would flow - perhaps hiles drilled around thermostat - that would ensure flow all the time but also mean that it would take longer to heat up to running temp as ALL the water would need heated first.

IAn

[mgbv8]

Drill an 8mm hole in the flange of the thermostat, and fit the thermostat with the hole at the 12 O'clock position. This will serve two purposes. 1 to ensure enough bleed by to ensure some decent flow before the stat opens. 2 to make sure any air pockets in the manifold are cleared on startup.
This solved my problems on my 4.6. Why didnt they think to put the by-pass at the 12 O'clock position in the first place?

[katanaman]

a proper rover stat has a hole at 12 for that very reason.