learn me how to bleed a cooling system.

When I built my racecar I installed the radiator lower than the head. If I had realized what a pain that was I would not have done it. But it is what it is now and I have to live with it. So in order to get the air out of the head I jack the front of the car a foot and a half in the air and run it with the temp sending unit (highest point in the head) cracked to bubble the air out. It takes forever and the temperature skyrockets the whole time. And even when I think I have it bled it usually heats up the first time out on the track.

I am sure there is a better way and I am equally sure one of you guys will school me.

I like the water bottle with the bottom cut off as a funnel. Usually seals into the rad then jack up the front if needed and add coolant to the bottle funnel until the level is the highest point. Crank, rev up to dislodge bubbles. Or you can put an inline radiator cap in somewhere and make it the highest point.

Install a bleeder screw in the top of the water neck. Or space out the temp sender and put a screw there. Every 2.2 Cavalier in the junkyard has a nice two piece brass bleeder on the upper water neck.

A small auxiliary tank like the short track guys run is a good solution. Mount it on the firewall and use a pressure cap with lower pressure than any other caps in the system. Plumb it so that there will always be liquid coolant in the aux tank. (The aux tank must be the highest point in the cooling system. Steam in the cylinder heads is BAD)

Rog

Vacuum bleeding doodads are magic, particularly if you are trying to get heat in a 2004 Maxima. You can turn those buggers upside down and there will be a bubble in the heater core.

For a race car, where the vacuum bleeder may not be convenient at the track, I go along with the pressurised tank at the highest point. Add a (pressurised) bleed line from the thermostat housing, or whatever is the highest point and the top of the radiator to the pressure tank and you are golden. Look under the hood of any Volvo built since 1975 and you will get the idea.

WRX's have a small pressure tank in the system that sits right above the RH cylinder bank.

why does the engine overheat when you are bleeding the cooling system? the engine doesn't need to be running... pull the upper radiator hose and thermostat out and fill it... then put the hose back on and fill that.. if you have an overflow tank- and you should always have an overflow tank- fill that up most of the way, too, and start it up..

on fully functional street cars, i usually pull the highest heater hose off and fill the system until the coolant runs out, then fill the hose with a funnel and jam it back onto the heater core. if i'm feeling ambitious, i'll pull the upper rad hose off and fill that, or just fill the radiator up and gently squeeze and release the upper hose like a turkey baster and refill the radiator as the level goes down until it won't take any more coolant.

I've never had a problem in my F150 by just running the truck with the cap off and letting the air find it's way out.

Seems as easy as finding the highest point and installing an outlet for the air. At least temporarily.

often times that doesn't work to get some of the very stubborn trapped bubbles out

+1 for adding a bleeder screw at the highest point.

One of these. Uses your air compressor to pull a vacuum on the whole cooling system vi venturi action, then you stick the hose in the water/coolant you want in the engine and let the vacuum suck it in. Easy peasy.

In reply to wbjones:

Bubbles where? That'd be the question to answer. Unless you know where the bubbles are, you're just shooting in the dark.

that's why the "raise the nose of the vehicle as high as you can" theory gets as much play as it does … as best I can figure, you NEVER know where the bubble(s) is/are …

and they can be a real PITA to eliminate sometimes

electric water pump so you don't have to run the engine to circulate the water get rid of air?

Thanks for all the suggestions. I am going to try the vacuum gadget although me being me I will build something with a shop vac and spare house plumbing. I have tried all the listed suggestions including a remote fill with a second cap on the firewall, and every 'get the air out' trick I could think of. It sits in the head somewhere and will not move for any thing.

Have you got a bleed hose at the top of the engine? Unless you have a p[lace for the air to go, its going to sit there til hell freezes over.