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Upper radiator hose high pressure

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slickonice

10+ Year Contributor
37
0
Feb 22, 2009
new orleans, Louisiana
So after driving my gsx around tonight i noticed a bit of steam coming from the hood. I checked it out and it looks to be my overflow bottle. It's been getting more full of coolant every time i look at it. And my upper radiator hose is hard as a rock and bloated like a pig. It has a 13 psi radiator cap from auto zone.
I was reading and people were saying its probably the head gasket. My coolant looks fine and the oil isn't milky or anything. Could the thermostat be the issue?
Thanks!
 
does the UPER radiator hose get hot ? IF IT DOESNT YOU COULD HAVE A BAD THERMOSTAT, BROKEN WATER PUMP OR CLOGGED RADIATOR
AND IF IT DOES GET HOT, THE MOST PROBABLE THING IS THAT YOUR RADIATOR CAP IS NOT WORKING LIKE IT SHOULD, INSPECT THE GASKETS OF THE CAP THAT GO INTO THE RADIATOR.
 
okay thanks, i'll run to auto zone tomorrow. I'm not overheating at all. The upper radiator hose gets hot to the touch. I didn't check the lower one though
 
check the lower 1 if its not hot try a new rad. cap and thermostat and not all bad headgaskets leak into the oil some leak external best way to find out is a compression test
 
Well just get a new thermastat and coolant temp sensor they are both like $15 or less at autozone, both are a cheap and easy fix, try that first.

Coolant temp sensor has nothing to do with your problem...so dont wast your money on one. Pull your thermostat put it in boiling water make sure it opens and closes. If it doesn't that could be your problem. If it does then you might have issues somewhere else. A blown head gasket doesn't always mix oil and coolant, It could be blown and pushing coolant. You could also have air in your system also. A bad radiator cap could also cause the same issues you are having.
 
Another thing, my overflow bottle got burned a while back and the cap doesn't really seat or seal, it just kinda sits on top. That wouldn't cause problems, would it? And I just took my car for a drive and when I get back checked the radiator hoses. Top one is hot and puffy and lower one isn't nearly as hot.
 
high pressure in the upper hose could be a thermostat try testing it like stated earlier in boiling water
 
okay, i'll pull it out and test in boiling water. Thanks for all the input!!
 
just buy a new radiator and cap both cheap and will probably solve ## issue
 
The radiator is an aluminum mishimoto with about 2 months on it. I'll pick up a new cap in the morning, hopefully that does it.
 
yeah i ment thermostat and radiator cap sorry its like 1 in the morning here
 
i'll run to auto zone tomorrow
Stay away from "AutoSHITzone" junk! Get you a better cap from NAPA or similar.

I had the same problem happened last summer and outside of a cap that went bad, I did a system flush with taking out the radiator and flushing the crud out of that thing along with flushing out the heater core before I restored my system. I got a 13lb cap from NAPA and my system is back to normal.
 
okay well today I replaced the radiator cap and the thermostat. The old thermostat was pretty crusty and I couldnt get it to open up with boiling water. It seems like this helped, the hose doesn't look as bloated anymore.
 
Since the hose swelled up I would recomend replacing it before it bursts. They strecthing of it has probably caused it to be weaker. They should only well slightly when hot.
 
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