: Overheating Northstars and bleeder valves

08-23-12, 08:41 PM
Hi gang!
The other day I was browsing through the forums, and I ran across a post about someone who adapted a home heating "steam pressure relief valve" to the bypass hose, and said that he drove it like that for a year or so with good results. There was even a picture of the product! I've tried to search for it but can't find it. Does anyone recall that?

Thanks in advance!

08-23-12, 09:05 PM
I vaguely recall it. It's just a Rube Goldberg band-aid that may or may not work, depending on how far along your HG failure is.

08-25-12, 11:02 AM
I suppose it would work - sort of. A pressure relief valve implies that it would bleed off at some pressure, but there would be no way to bleed only gas - anything would blow out when the valve tripped - just like our coolant reservoir caps vent both gas and coolant with ease........

Another idea: A Nash Float Valve. There are several versions of the Nash Float Valve - several were used in submarines to remove air from ballast water pumping systems.

The valve is placed at the high point in a system. (and that's a problem in a car engine room) It uses a float and tapered pin arrangement in a cylinder with a drain hose: Air in the system causes the float to drop, the tapered pin drops, and air bleeds out. As the loop fills with water, the float again closes the bleed hole.

Mom & Dad's old home near DC had a 1920's version of the float valve in the 3rd floor at the header tank for the hot water radiator system.

Remember the Northstar overheating sequence due to failed head gaskets: The intruding exhaust gas overpressurizes the cooling system, which then dutifully vents off gas and coolant through the pressure cap relief. At some point the coolant falls dangerously low, the water pump loses pumping action due to cavitation, and the engine overheats. The exhaust gas, in and of itself, does NOT "overheat" the engine. The loss of coolant flow does.

08-25-12, 09:54 PM
I thank you both for your response! I finally figured out that my description was in error. It was a "Air Bleeder Valve". I found one and ordered it. I'll install it and let you know how it works out.

Thanks again!!!

08-26-12, 09:27 AM
I'll move this over to Engines; Northstar Performance. Maybe there are other ideas, like the Rube Goldberg secondary purge line arrangement (for removing exhaust gas from a compromised cooling system) that is part of a so-called "engine block sealer" kit.

08-26-12, 11:53 AM
One more thing to think about.

When we first picked mine up, we used it to take the kids to school (about 12 blocks, round trip).

People were referring to it as a "stream locomotive" as the white smoke would pour from both exhaust pipes.

HOWEVER, one day I checked the oil & it was white & foamy.
The coolant was getting dumped into the block as well.

I stopped driving it right then until I could get the time to redo the head gaskets.

ANYTHING other than oil in your oil can be bad on your bearings.

08-26-12, 12:22 PM
Coolant in the oil due to head gasket failure in a Northstar is highly unusual but not unheard of - your case must have been extreme.

09-16-12, 11:52 PM
Hey Carroll1, I'm interested of the air valve trick worked? Got same problem going on. Need advice. Not going to get engine redone. Just trying to keep her going for awhile. closer 479 at gmail dot com. email me.

09-17-12, 07:54 PM
Hello smokin!
The “air bleeder” seemed to help the problem of explosive overheating, but alas, it wasn’t enough help in my case. It worked well as long as I didn’t leave the city limits, but if I tried to visit a town 15 miles away, I didn’t have a problem getting there, but coming back home it would invariably start overheating. And in my case that meant lost coolant.
Under my normal driving requirements that wasn’t a major problem, however I have a lot of relatives that live 250 miles away and many of them are not well, so there was always the uneasiness of an emergency trip to their hospital, or worse. In short, I needed a more dependable vehicle, so I sent the Cady to the crusher and bought a Taurus.
Like you, an expensive repair was never an option. If you think that this will work for you, give it a try. It wasn't expensive and an easy installation.

Give me a shout back and let me know what you think.