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Bad head gasket without overheating?

D

DeadStang

Member
The car pukes and pukes out of the radiator overflow, but it is not overheating--driving it runs right in the center of the stock gauge (and I've checked it with an laser thermometer as well). I read this from another thread:

"Now on a side note, If your getting a repeated coolant purging or small air bubbles in the coolant stream after warm up.
You have a seeping head gasket condition. Compression gases are being forced into the cooling passages and will purge the coolant.

You can eather get the test kit that uses a dye to reveal exh gases in coolant or try the ballon trick by closing off the overflow tube and stretch a balloon over the filler neck while it idles. If the balloon inflates, there is gases being pushed in.
Another way is after you have the rad completely topped off, run the engine at 2500 rpm for 2 min and shut it down.
If the coolant starts purging from the overflow you have gases present."

Perhaps it's a very small leak, so it's not overheating (yet)? After each drive, I need to add about 1/4 of a gallon of radiator fluid... I realize that I am overfilling each time and it will puke some coolant to equilibrate, but I've never had a car that likes the coolant level to reside below the first row of metal in the upper part of the radiator (I always see a little coolant over the metal, when looking into the top of the radiator). This is a very old block, so I assume there's some rust being liberated with the antifreeze, but there is definitely a rust/red color to the used antifreeze that's puking (along with the green), which was a symptom of my last bad head gasket...
 
It's certainly possible. We had a similar issue this race season and except for a little water in the oil, you'd never have known the head wasn't sealing.

I'd use one of the gas testers on the radiator and see if the results reveal anything interesting. You might also look and see if either of the rad. hoses are swelling, but then again, it doesn't sound severe enough that you would notice.
 
Adverage coolant level is just below the caps neck but above the cooling rows.
From your description you have a coolant purge happening.
1st sign of a compression seeping head gasket, A possiable fix is a simple retork of cyl head bolts could be just what it needs.
But if let go too long a gasket replacement will be in order to fix the problem.
 
"Mach1Rider" said:
1st sign of a compression seeping head gasket, A possiable fix is a simple retork of cyl head bolts could be just what it needs.
Click to expand...

Do you think that this would be successful in a motor that is not even remotely "fresh," ie that's 40+ years old and never been opened?
 
I realize that I am overfilling each time and it will puke some coolant to equilibrate, but I've never had a car that likes the coolant level to reside below the first row of metal in the upper part of the radiator (I always see a little coolant over the metal, when looking into the top of the radiator).
Click to expand...


Are you 100% certain that you're not simply overfilling the radiator? My radiator is a big aluminum aftermarket crossflow... and with the cap removed on a cold non-running engine the coolant level is WELL BELOW what you've described as your "normal" fluid level. Upon startup, coolant is drawn from the overflow tank and upon shutdown coolant is added to the overflow tank. Are you using an overflow tank?


The car pukes and pukes out of the radiator overflow, but it is not overheating
Click to expand...

Does it ever stop "puking"? Or is it just puking until a certain level of coolant is expelled from the radiator? Normally, a blown head gasket would have other symptoms in addition to what you're seeing. That the car is running fine and not overheating leads me to believe that it might not be a blown gasket.
 
This is my "dead-for-30-years-Comet" that I just got driving Labor Day weekend. To be honest, I haven't driven it very far or very many times (maybe 1/2 a dozen) as the rear end makes noise and I haven't totally straightened out the brake light and turn signal issues.

No, no coolant overflow tank. Stock 289, no A/C radiator.

It seems to expel the majority of the fluid in the initial 15 minutes of running, beginning once the thermostat opens. But it continues to drip and to overflow small amounts (visible drips) for the rest of the drive and continues dripping for a bit once stopped. The farthest I've taken it was a 25-mile round trip.

Things that makes me suspicious of the head gasket is:

(1) The motor has sat for 30 years, the last 20 of which doesn't appear to have been started. Seals and gaskets start to leak after awhile?

(2) The excessive overflowing and the fact that the water level it seems to equilibrate to being below the level of the cooling fins. I have a couple of other Mustangs and I tend to overfill the stock radiators in those initially as well, but after they puke and stabilize, none have bare cooling fins visible, ever.

(3) The coolant is red-tinged green. [Yes, it may be rust from the block, but my last bad head gasket in a 351W car had rust-colored anitfreeze, although it blew white steam out of the exhaust.]

I know they sell coolant test kits at Napa, but I believe they are expensive and not very reliable. I'd be happy to spend the buck$ for the kit, but if it's not reliable, I don't want to waste the money.
 
Well a cheap test for gases is taking that condom out of your wallet and put it to some use. :)
No no that way.
With the rad topped off and air purged (eng at operating temp hearter on and stat open), Plug the overflow tube off and stretch the condom over the neck
And start the eng and let it run for 20-30 mins varying eng speeds.
Watch to see if the balloon starts to inflate, yes there will be some inflation with the heat of the coolant. But if it grows larger than just being straight and round, you have combustion gases entering the coolant passages from one or more of the cyl.
 
OK. Hmmm...where can you buy just one rubber?--I don't want a box. LOL! Perhaps one of my daughter's balloons will work as well.
 
"Mach1Rider" said:
Well a cheap test for gases is taking that condom out of your wallet and put it to some use. :)
Click to expand...

LOL.....I doubt she carries a wallet, let alone a condom in her wallet. :lol
 
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