Getting air out of coolig system...

[wood_e]

Getting air out of cooling system...

I believe I have air in my cooling system as my hoses collapse when they're cold. How do I get air out of the system?

 

[Ishodu]

Sounds like you are in need of a new rad cap or your line from your rad to your reservoir is plugged. When the system cools it contracts and creates a vacuum and sucks coolant from the reservoir. So your system is staying under vacuum.

 

[SHOZ123]

Your cooling system should purge itself of any air over a few heating/cooling cycles.

When the coolant heats up it expands and pressure builds in the radiator. At this time too the air in the engine will dissolve into the coolant because it is under pressure. When the pressure reaches the point that the cap is working at, it will open the cap and the coolant will pass to the reservoir relieving the excess pressure and carrying the dissolved air along with it.

As the coolant in the reservoir cools the air becomes "undissolved". And as the coolant in the engine block and radiator cools the cap again opens and pulls the coolant back into the radiator.

If you have your hoses collapsing upon cool down, then the coolant is not being pulled back in. Perhaps the bottom of the reservoir tank is full of sludge or the radiator cap is bad.

 

[SHOfun 93]

My problem is that the upper radiator hose won't pressurize and the temps are getting as high as 210 with a 180 degree tstat! Air in the system, possibly? But I thought that air would make the upper radiator hose HARD and not allow enough coolant to pass through the tstat.....was running fine earlier today, and I pulled some coolant lines above the inlet neck, including the upper radiator hose in order to install the Autometer water temp sending unit, and now the darn thing won't pressurize...could it be air in the system from all the lines I had disconnected? We'll see..I topped off the overflow bottle and hope for the best....

 

[DHMag]

if your t-stat has a "jiggle" valve(its actually a oneway check valve) in it, it goes on top when installed. it allows air/coolant to purge one way but not the other. this allows the air to purge quicker than waiting 2-3 heat/cool cycles. when filling the radiator, i squeeze and release the upper radiator hose to assist in purging the air from the system. i do this until i no longer get air bubbles at the filler neck.

 

[SASHO91]

hey dale when i purchased my t-stat, it didnt have a jiggle valve. But i had heard that, if you drill a hole, its has the same affect. But i have not had any problems. it runs very cool on the highway. Most of the time its at the L, and even after a nice run, its still not that much above the L. Sorry for the Thread hijacking, but i figurerd it might be helpful also.

 

[DHMag]

hey dale when i purchased my t-stat, it didnt have a jiggle valve. But i had heard that, if you drill a hole, its has the same affect. But i have not had any problems. it runs very cool on the highway. Most of the time its at the L, and even after a nice run, its still not that much above the L. Sorry for the Thread hijacking, but i figurerd it might be helpful also.

i forgot to include the option of drilling the hole. thanks for the heads up