Wondering the best way to burp air out of cooling system?

[Wheels]

Subject says it all.Thanks.

[A Snake]

Two things:

I don't know what kind of radiator you have, but you need a small AN line from the top of the passenger side (radiator) tank to the surge tank. It is called a purge line and any air in the system will be in the top of the surge tank, which is where it belongs....not in the radiator.

If you have the Galaxie surge tank, take it off and have your radiator shop install a fitting. It goes on a flattened round spot on the bottom front right side of the surge tank.

If you go to my gallery, you can get the general idea from the picture entitled "Plain but Potent" The blue and red AN fitting you see coming out of the surge tank makes a short bend and connects to the radiator.

The radiator also needs to go to the shop to have the fitting installed. I don't remember the AN numbers now, but the ID of the line is 1/4".

This fix will end your air problems, provided you have a similar set-up to mine as far as having the Galaxie or similar tank mounted on your 427.

Hope this helps.

Al

[Steve Dickey]

Wheels,
Drill a 1/8 or 3/16" hole in the top flange of your thermostat, this will help the trapped air escape. If you have a plug or temp sender high on your manifold remove it while you are filling the radiator till water comes out. I have a valve at the top of my radiator I also crack while filling.
Good luck, Steve

[decooney]

If all else fails, try this. Jack up the front of your car (same height as if it's on drive up ramps), open the cap on expansion tank if you have one on your FE; making the expansion tank at the highest point.

If you have an expansion tank, and it trickles out small bubbles at a time, try letting it sit for a few hours or overnight. Be sure the tank is at the highest point in the system including hoses...

f you don't have an expansion tank, remove the water sending unit/plug instead on the front of your intake manifold (if you have one) and let the water trickle out there for a bit. Watch for air gaps as the water bleeds out the hole, then close it off after a fair amout of water has escaped with no air gaps there.

This has worked for me several times and never had a problem since with my last two Cobras

[A Snake]

Good ideas Steve and decooney, but if the purge line is installed as I suggested, there will never be any need to bleed while filling or otherwise.

BTW Steve, I believe drilling holes that size in the thermostat tends to defeat it's purpose to some extent. one hole 1/16" would be more than enough. It doesn't take a very big hole to let out air. Especially under pressure.

Al