car overheats

[slowbubblecar]

I am pretty sure the HG is the problem. I might pull the thermostat out and drop it into boiling water to see if it opens to see if it is fine, but I am planning on replacing the HG anyways since it was blown out the 2ng pull. We torqued the head studs to 95 try to seal it again. It holds during boost, but I am guessing it still might be the problem. My brother said there was white stuff coming up with the filler cap off so I am pretty sure it is the HG. I am going to make sure the head isn't warped before I put it back on to make sure it isn't the reason it blew out in the first place. The car was tuned pretty good so I have no idea how it blew out in the first place.

[JET]

Just take the thermostat out and run it.

[MATCHBX]

Air bubbles can only get from the headgasket. And other place where coolant would leak would be an external coolant leak. Not bubbles in the coolant.

Wiz

This is not the only way air is introduced into the system. Granted he has a new waterpump on it, but if the seal goes out in the waterpump it will introduce all kinds of air into it with very minimal external leakage. The only leakage seen when the seal is bad (or the shaft of the pump is grooved) is after it's shutdown. And then it sometimes is only a tiny bit that doesn't make it all the way to the ground.

And it's not recommended to rev the engine with the cap off. The radiator cap is a two-way valve for that purpose. The system will push coolant past it at a set pressure. But when the thermostat opens, it draws coolant back into the system via the little poppet in the center. You can let it idle with the cap off, but use the techniques that Shane and those were talking about with the funnel to keep the level always above the engine so it is never starved for coolant.

I agree with Jet, eliminate the easy stuff first. Take out the thermostat and run it to see if it does the same thing. It could be that the thermostat sticks a little and then opens up, thus creating erratic readings. But it would probably be pushing the excess coolant out into the overflow. It could be just enough that it doesn't overflow out of the bottle before it gets sucked back in.

[slowbubblecar]

The car still overheats with no thermostat in it. What would you do? HG? I am pretty sure coolant gets sucked into the overflow bottle but doesn't get pulled back it.

[JET]

Yep, it sounds like a minor HG problem. As long as the radiator cap is sealing well and is good, then that is probably what it is.

[slowbubblecar]

Thanks