Stuck Coolant Bleed Screw

[Stevehose]

You won't eliminate all the air from the top hose, the goal is to eliminate it from the thermostat. I blow into the tube until the coolant just comes out then put my thumb over it and then slip it onto the overflow tank, trying to minimize any leakage while doing so. Put rags everywhere. Coolant...I hate coolant.

 

[aearch]

YOU CAN ALWAYS DRILL IT OUT AND MAKE A NEW ONE FROM A BOLT
MAKING IT STRONGER THAT WONT STRIP AGAIN
I DID THAT

 

[Peter Coomaraswamy]

So I think I've managed to bleed the coolant. No more bubbles. However, when in my garage at a standstill the engine still runs hot. But, when I take it out and drive it around the block the temperature drops off very quickly to a much lower and manageable temperature. This to me suggests that at idle with the car not moving, the fan is not effectively cooling the engine! Or, maybe it's the air not flowing through the rad that's my problem?

Anyone experienced similar situations?

As for the water pump. I just put a new replacement on a few weeks ago. The old one wouldn't even spin when I got it!

Hello Scanty,

It may be helpful if we know a little more about your car, what year is it, what year is the head, is it injected or does it have carbs? Some of these things can point you in a better direction. Also, does the aux. fan come on when the temp goes up? Older (or original) heads have more over heating problems than later heads. If you could be a little more specific the group can probably help more. And you have the guru SF Don up there in the bay area as well

Best of luck

 

[Stevehose]

Scanty is long gone, this thread is almost 8 years old. We're answering Bo's question about the bleeding technique. Carry on

Hello Scanty,

It may be helpful if we know a little more about your car, what year is it, what year is the head, is it injected or does it have carbs? Some of these things can point you in a better direction. Also, does the aux. fan come on when the temp goes up? Older (or original) heads have more over heating problems than later heads. If you could be a little more specific the group can probably help more. And you have the guru SF Don up there in the bay area as well

Best of luck

 

[Peter Coomaraswamy]

Well no wonder we never found out what was causing his problem... geeze

 

[Ohmess]

The purpose of this technique is to get all the air in the system to the top of the expansion tank. When you do that, a properly filled cold system will have 1.4" of air in the top of the expansion tank. Because the nipple that the hose connects to is within this 1.4" gap, there will be air in the portion of the hose that is above fluid level (i.e., the end of the hose attached to the expansion tank, but not the relatively lower end connected to the radiator). This is true if you use the finger over the end method that Steve uses, or if you simply install the hose after you blow the air to the top of the hose as I do so long as you do not allow the end of the hose to dip below the coolant level in the expansion tank. I don't use the finger over the end method Steve uses because with the proper level of fluid installed in the system, the coolant will "find its level" within the system when you reattach the upper hose whether you trap some fluid in the upper portion of the hose or not so long at you do not allow the end of the hose to drop below the fluid level in the expansion tank when reattaching it.

Again, your goal is to get all the air in the system into the top of the expansion tank where it belongs.

 

[Honolulu]

Late to the party... I think it was the Hack Mechanic who suggested (as have others I'm sure) to melt some parrafin (wax) on the offending nut or bolt when it's hot. The melted wax will wick into the threads just like the fancy stuff is supposed to, but wax costs orders of magnitude less than Aero-Kroil, PBlaster, even less than WD-40. There's probably a Youtube video about which works better...

 

[Ohmess]

Late to the party... I think it was the Hack Mechanic who suggested (as have others I'm sure) to melt some parrafin (wax) on the offending nut or bolt when it's hot. The melted wax will wick into the threads just like the fancy stuff is supposed to, but wax costs orders of magnitude less than Aero-Kroil, PBlaster, even less than WD-40. There's probably a Youtube video about which works better...

Yes, it is expensive, but I have had excellent luck with Aero-Kroil. Scrape around the perimeter of the bolt or nut with a pick to remove as much dirt and corroded crap as possible, then spray with Aero-Kroil and let it work in for fifteen minutes. If you have the tstat out of the car, scrape and spray the underside of the bolt in addition to the top. Spray again and then instead of trying to loosen the bolt, change direction and try to tighten the bolt just enough to get it to move. Once it breaks free, change direction again and it should back out.