hi idle/coolant

[no-red 6 0]

just thought of this...

the other day when our mechanic at work was checking my batteries, i had the hi idle switch on and happened to see coolant shooting out of the return hose back into the coolant tank.

has anyone else seen this or know if that is what is supposed to happen? what is going on.....

 

[powerboatr]

just thought of this...

the other day when our mechanic at work was checking my batteries, i had the hi idle switch on and happened to see coolant shooting out of the return hose back into the coolant tank.

has anyone else seen this or know if that is what is supposed to happen? what is going on.....

yes under normal instances it should be squirting some coolant back into the bottle, its actually uneeded/excess flow,
its should also be dependent on engine temp/eng speed/outside air temp/etc

 

[no-red 6 0]

squirting back constantly? it did not stop.

keep in mind i live 2-3 blocks from work. started truck, 2-4 min. idle, drove to work, thru on hi idle walked in to find him and we came outside. so i'd say it was only running 10 on a butt azz cold day.


even better
t stat hadnt opend up fully yet so lots of cold coolant running around
check it after shes HOT and see if it drops off considerably. but still flowing

 

[bushpilot]

mine does it w/out the hi-idle on...its basically
circulating the coolant...and if the hi-idle is on
then water pump is gonna be spinning faster...so
you should see "greater" pressure in the cirulation
back to the degas bottle

this is also why a coolant by-pass filter works, when
tapped to the lines of the degas bottle...

one thing that you might be thinking is that on our trucks
the degas/coolant bottle mounted on the firewall is NOT
an over flow tank like on OLDER cars....its really part of
the circulating coolant system.

 

[Kleetus]

What is this line coming from? EGR cooler? Is this what you guys with the coolant filter have spliced into?

 

[no-red 6 0]

bush/pb:
i guess as i re-read your posts it all makes sense and YES i do understand that the tank IS part of the system rather than an overflow. but you know what, i had (have) just never seen it doing it. uumm the hood is always closed....duh!!

ok, with that diagnosis - and coolant being shot back into the tank (i would assume most of the time) wouldn't the coolant get thinned/aerated/foamy like and over time (sooner than later) become not as effective. meaning should we not be changing our coolant (w/ or w/o a filter) sooner?

 

[bushpilot]

there should NOT be any air in your coolant system...
if you have air in your system you COULD get a hot spot
or vapor lock...

the cap is pressurized (and theres room in the degass tank
for expansion) for exactly this reason...so that any air IN
the system will bubble up to the high point (the degass bottle)
and be pushed out the coolant fill cap (if it gets too high in pressure).