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[RESOLVED] Boiling Coolant. No heat in car, over flow!!

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EclipticalGS

10+ Year Contributor
1,449
19
Aug 25, 2008
walker, Michigan
I am not writing this for a problem any more. I fixed it today . Every single search found nothing similar to my symptoms, but i fixed it today with my own luck.

--My weather conditions are michigan weather. THIS PROBLEM STARTED HAPPENING IN 10 DEGREE WEATHER !!!!

1. My car would heat up in 20 seconds but not overheat.......

2. My car would literally blow air at the weather temps.

3. After i stopped after a trip, the coolant plastic box would be boiling, and shooting out of the breather tube.

4. After a while of this, the coolant level got so low because the breather tube was losing so much coolant, that there were obvious air bubbles in the system.

5. In michigan weather 50/50 coolant is not fun at all, it ended up that the day the temperature hit 10 degrees, there was too much water in my coolant and it ended up getting frozen inside of my heater core. The heater might have broke, but thankfully i only drove like this for a mile from gf's house.

--Checked oil, no clouds, if there is clouds, could be blown headgasket, or oil seal, but not in this case.

6. I took off the stupid thermostat thinking that was it and of course it wasnt, but i replaced that sucker anyway.

7. I found the line forcing hot coolant too the Heater core (supply), and the line returning from heater core (On a GS, on runs off a T by the radiator, and the return runs to the T-neck where the thermostat is, they both meet together on the right side touching valve cover and run back to Heater core)

8. I unhooked both lines and tryd to suck and blow through to see if any thing could get through my heater core..and i couldnt push air for dear life. So poured boiling water down the tube and let it sit, and kept forcing boiling water down there until it finally got the ice broken up. Then i blew through the return line, and ice and gunk started shooting through the supply line..after minutes of blowing i found that it was finally clear.

9. then i put the SUPPLY line back on its nub...and filled the reservoir and the T-neck full of my own 80% solution with distilled bonding water . Then i sucked on the return from heater line to get all of the coolant somewhat circulating, i got a lot of air and gurgling..burps from radiator especially ### it was running low on coolant for some time before the heater core froze.

10. Tasted coolant through the return hose and just let it syphon into a bottle while refilling the T-neck with my stuff when it got low. Completly changed out the fluid, drained the Radiator too to get bubbles out.

Full flow, now and hot air, engine goes nowhere over half heat, stays at 25% gauge. No more boiling noise when i stop anymore.

Just wanted to say this because I know when i really need a fix, there sometimes are people saying 10 different things and it really makes me scared thinking my head was warped when this was really the problem and it was not too bad. only 3 hours messing around in 10 degree weather.

Remember that this is only for the symptoms stated above ^^^ It was a clogged heater core.

THanks .....
 
Now, when things warm up in the "mitten state", I would do a total drain and system flush to rid of any rust, gunk, et.al., and fill with 50/50 mix.

Also, since you got the 420A motor in that thing, take the T-stat out and drill a small .050 hole in the flange (if the T-stat doesn't have that jiggle valve..and that jiggle valve still needs to be at the 12:00 position when installed) and put the hole at the 12:00 position when putting it back in. That hole helps to burp all of the air out of the system...the way that T-stat is mounted is a typical Chrysler fubered design thing...being their motor.

Also, since you resolved your problem, goto the top of your post and click on "Thread tools" and click on "resolved" - doing this will put the word "resolved" in brackets at the beginning of your topic for this thread to let the rest of us know that this problem listed has been taken care of.

good luck- DSM
 
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