Coolant Gushing Out...

jrp27540 · Sep 17, 2016

So I just changed the heater core in my 88 LX. After letting it warm up, coolant is gushing out into the overflow container. Figured there may be air in the lines, so I pulled of the radiator cap. Let it run for a bit and coolant started gushing out of the radiator cap. I'm not sure what's going on. I turned the heat to hot, but no hot air is coming out. Is there just a punch of air in the system and just needs a good flush?

stykthyn · Sep 17, 2016

Sounds like it. Jack up the front of the car so that the radiator cap is the highest point. Let the engine run until the Tstat opens. This should allow any trapped air to escape.

mikestang63 · Sep 17, 2016

get a lisle funnel and burp all the air out of the system. Make sure the heater is on max and hot.. No need to jack the car up with the funnel. best $25 you will spend.

stykthyn · Sep 17, 2016

mikestang63 said:
get a lisle funnel and burp all the air out of the system. Make sure the heater is on max and hot.. No need to jack the car up with the funnel. best $25 you will spend.

I still need to buy one of those

jrp27540 · Sep 17, 2016

mikestang63 said:
get a lisle funnel and burp all the air out of the system. Make sure the heater is on max and hot.. No need to jack the car up with the funnel. best $25 you will spend.

So this begs another question. The previous owner deleted the A/C. I have a strong feeling the vacuum system for the heating/cooling system. The air only blows out the defroster only; I cant get it to change locations. The cold/hot switch is also hard to turn. I can see the blend door cable moving behind the glove box when I change the heat, but im not sure its doing anything inside the box... Im concerned that I cant get the "heater at max hot" if its not working properly. Is there a vacuum diagram out there for the cooling/heating system? I have been looking around with no luck. Im guessing the vacuum line to change the location is missing.... It looks like its there under the dash, but I know there is a location under the hood that a vacuum line comes to for that control.

Thanks for all the help!

jrichker · Sep 17, 2016

The following are diagrams courtesy of Tmoss & Stang&2birds

HVAC vacuum diagram

LiquidStangs · Sep 17, 2016

jrp27540 said:
The air only blows out the defroster only; I cant get it to change locations.

Same thing happened to me. It turned out to be the vacuum line running from the vacuum tree to a connector on the passenger side, running across the bay right by the firewall. Mine was originally this thin plastic thing which was brittle after all these years. Replaced it with real vacuum line, and the different settings now work.

jrp27540 · Sep 19, 2016

LiquidStangs said:
Same thing happened to me. It turned out to be the vacuum line running from the vacuum tree to a connector on the passenger side, running across the bay right by the firewall. Mine was originally this thin plastic thing which was brittle after all these years. Replaced it with real vacuum line, and the different settings now work.

Yes, I believe this is my issue as well considering he just put a cap on the vacuum tree for the A/C, which I think controls the location of the air being blown. I see the vacuum tree connector on the passenger side...but no vacuum line running to it from the vacuum tree. Going to get some vacuum line tonight and hook it back up.

jrp27540 · Sep 28, 2016

Just to follow this up. I got a lisle funnel and was able to burp all the air out of the system. The heater is working as expected now. I haven't had a chance to get the air to change vent locations, but im 100% positive its due to the missing vacuum line. Ill try to get it going this weekend. Thanks for the help everyone!

Coolant Gushing Out...

jrp27540

Active Member

stykthyn

I want to measure mine. It doesn't look that tall.

mikestang63

stykthyn

I want to measure mine. It doesn't look that tall.

jrp27540

Active Member

jrichker

StangNet's favorite TOOL

LiquidStangs

Well-Known Member

jrp27540

Active Member

jrp27540

Active Member

Similar threads

Coolant Gushing Out...

Active Member

I want to measure mine. It doesn't look that tall.

I want to measure mine. It doesn't look that tall.

Active Member

StangNet's favorite TOOL

Well-Known Member

Active Member

Active Member

Similar threads

Privacy & Transparency

Privacy & Transparency