Interior and Upholstery Flush ac evaporator

billyp

Member
Jul 30, 2019
9
3
13
Colorado
I've got a 91 5.0 that I'm replacing the original AC system except the evaporator. A couple days ago I used a can of ac flush on it. I've used compressed air half a dozen times and I'm still getting flush liquid out. Not much but still some.

How dry does it have to be before I can trust that the vacuum pump will boil the rest out?
 
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Can you connect the vac pump to the evap and pull a vac on it now, without needing to hook up the rest of the system?

I think I would want it all out completely. I have a feeling it's just sitting at the bottom of the evap core so you really need to get it out otherwise any contamination in it will flow and clog the orifice or compressor
 
I just did one using a flush gun from amazon? Four uncles was the brand but it did a great job with the flush I got at autozone,that flush evaporated quickly.And yes you can see cra P being flushed.
 
Can’t you shop vac it? Use some duct tape to connect a smaller hose on there and connect to the lower port. I feel like it should generate enough suction to remove it.

Then id flush it again. You really want to make sure it’s clean in there.
 
I also installed the original air kit. The instructions say you can't flush it installed in the car. Guess we'll see. I have an 89 I did with a different kit probably 8 years ago. That one I just blew out with compressed air. Still works great.
 
Got the flush gun and it worked better. Also found from some videos that putting a rag over one end to build up a little pressure when blowing it out helps a lot. Running just air through it doesn't get everything out.
 
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I am going to take the front radiator piece out and clean it . Not removing the dash piece so that one you really have to work on. I never thought of the shop vac. Thats a great idea . Jrichker said paint thinner was ok to flush. Thats what I will start with. Its cheap and you can really pump it in there
 
Can’t you shop vac it? Use some duct tape to connect a smaller hose on there and connect to the lower port. I feel like it should generate enough suction to remove it.

Then id flush it again. You really want to make sure it’s clean in there.
I am not sure flammable liquids and a shop vac are a good combo.
 
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