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Radiator puking

Bill Monk

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440 6bbl
Radiator is clean, thermostat is good and less than a year old, nothing leaking, water pump checks out. Running 50/50 with a bottle of red line water wetter. The car does not overheat even in the really hot weather we've had. Temp gauge works and stays steady once warmed up. I had it out Sunday in 95 degrees for a 50 mile run with no issues. Most of it was interstate but some stop and go.
Here's the problem: For the last several times I've run it, when I shut it down, the radiator will puke maybe between a pint and a quart out the overflow. The first couple times I thought maybe I just had it overfilled but it didn't look like it when I took the cap off. After the run and puke Sunday, I checked it out and the coolant level is just over the core but a couple inches below the top of the radiator so I don't think it should have done that.
Any ideas?
 
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I run green coolant and leave about 2 inches to the cap too. Had an unexpected puke in LA on a trip. Did not top it off, and figured it was burping and looking for its happy level. OK ever since. Watch the temp and drive it.
 
I run green coolant and leave about 2 inches to the cap too. Had an unexpected puke in LA on a trip. Did not top it off, and figured it was burping and looking for its happy level. OK ever since. Watch the temp and drive it.
It may be nothing but the other cars (60s Mopar) I have had would run a higher level in the radiator than what this one has.
 
Install a puke bottle and forget it if not over heating. If no leaks it will pull back in what it needs.
 
Summit racing.

20180518_200117.jpg
 
coolant level is just over the core but a couple inches below the top of the radiator
I was going to say, a tad too much coolant and it is seeking it's own level, but that surely does not sound too high. Assuming you have the same factory radiator as I do, that is an awful lot of expansion.

Does this happen when running at lower ambient temps?

You said "Temp gauge works and stays steady once warmed up". What temperature is she running at?
 
I was going to say, a tad too much coolant and it is seeking it's own level, but that surely does not sound too high. Assuming you have the same factory radiator as I do, that is an awful lot of expansion.

Does this happen when running at lower ambient temps?

You said "Temp gauge works and stays steady once warmed up". What temperature is she running at?
It is a factory radiator, seems to happen anytime I run it hard even if I back it off and run it a while after a WOT run regardless of outside temps. I run a 195 thermostat because of the 6 pack. Temp gauge goes up to around the half mark with that thermostat. Can't say for sure what the coolant temp is during operation
 
I'd say you have a weak radiator cap that is letting it puke. Also, when doing the puking, check the radiator hoses to see if one is collapsing. Overflow bottle/container a good idea, should be the closed loop so it recovers the coolant.
 
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Do you let it idle for a minute before shutting off
to cool the heads so they do not boil
 
I'd say you have a weak radiator cap that is letting it puke. Also, when doing the puking, check the radiator hoses to if one is collapsing. Overflow bottle/container a good idea, should be the closed loop so it recovers the coolant.
I replaced the cap but that doesn't mean it's good
 
If it doesn't do it anymore, then it was just seeking level. If it does it again without topping it off, then it could be the cap.

When it does this during warmup, chances are a sticking thermostat.

Just keep an eye on it.
 
I'd say you have a weak radiator cap that is letting it puke. Also, when doing the puking, check the radiator hoses to see if one is collapsing. Overflow bottle/container a good idea, should be the closed loop so it recovers the coolant.
yeah, not collapsing
 
If it doesn't do it anymore, then it was just seeking level. If it does it again without topping it off, then it could be the cap.

When it does this during warmup, chances are a sticking thermostat.

Just keep an eye on it.
never done it during warm up or when I just idle it up to full operating temp, just after a run
 
IMHO- put a 180* t-stat in it. If you go with a puke bottle you need a rad.cap made for pulling a/f from it when it cools down(double gasket in cap).
 
I had this on my Hemi,re placed cap with 16 lb
Hasn't done it since
 
Another cap is cheap. I agree with oldbee about the 180 thermostat (I'm running a 6-pack too). Honestly, I'd try that cap & maybe install a mechanical temperature gauge (at least temporarily). Maybe give it another flush while you're at it.

Mine used to puke out of the overflow hose (no overflow in '70). I added a cheap "long bubble type" overflow that I picked up at a swap meet...many people sell them, about 16" long/6" diameter/drain lever on bottom....you need something for the track anyway. So....I later replaced my stock 26" radiator with an el-cheapo 4-core aluminum Champion (not the best fit, but works) and the car never puked again. My puking issue was the radiator not quite up to snuff.
 
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