AC went out after coolant blew out. Why?

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JJ Chalmers
Posts: 2
Joined: Tue May 01, 2018 11:37 am

AC went out after coolant blew out. Why?

Postby JJ Chalmers » Tue May 01, 2018 11:43 am

My 2003 Lincoln Town Car A/C was working fine until the car overheated and blew coolant all under the hood when the manifold heater hose nipple broke off. I replaced the intake manifold with a Dorman from Amazon, not hard but time consuming for me.

But then I had no AC. I can't see the connection to the coolant blowout, but it seems there should be a connection. Did all that hot coolant under the hood shooting out the heater hose nipple on the intake manifold, next to the evaporator housing, cause the R-134 to leak? Where? Why?

A shop put gauges on it and said there was no R134 at all in it. I ended up buying AC manifold gauges and a vacuum pump from Harbor Freight. With the pressure down to - 29 or -30, I saw it was leaking down when I had the pump off. But I could not tell where the leak was. I put a little R134 in it with some leak dye, and saw the dye at the fitting for the orifice tube. I replaced the tube (after breaking it off and learning how get the rest of it out) and put new O-rings on that fitting, but there was still a leak someplace unknown. I drew down vacuum again, and added 32 oz. of R-134, to the point the AC compressor clutch was on continuously, and there was cool air (61 F.) at the dash vents. I could not see any place the leak dye was showing, except for a little on top of the evaporator inlet tube where the orifice valve was. But the next day, no AC at all, and a funky smell inside the car.

I have had the car six months, only 89,000 miles on it, very clean. The previous owner had a new compressor, evaporator, accumulator /dryer, and O-rings put in about 8 months ago/4,000 miles ago (but the shop who did it won't cover warranty to me as a new owner).

Anybody have any ideas? I am thinking I should just go ahead and replace the evaporator and condenser and accumulator and hoses and be done with it; I believe I can handle the labor there.

This is my first time working on a AC system, so any ideas would be much appreciated as this Florida temperature heads into the 90s.
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Cusser
Posts: 302
Joined: Sun Apr 24, 2016 6:29 am

Re: AC went out after coolant blew out. Why?

Postby Cusser » Wed May 02, 2018 8:43 am

It would be easier and less expensive to have a "real AC" shop find the source of the leak(s). Better than throwing parts at it.
JJ Chalmers
Posts: 2
Joined: Tue May 01, 2018 11:37 am

Re: AC went out after coolant blew out. Why?

Postby JJ Chalmers » Mon May 07, 2018 4:35 am

It was the evaporaor core. That 200+ degree coolant blowout met the chilled evaporator core and cracked it open.

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