I felt like a little celebration...

Spurshot · May 1, 2017

I had to celebrate a little after testing my a/c evaporator tonight.

I made a vacuum test plate to check the condenser this afternoon. It checked fine.

That left the evaporator as the only component that was not new except the condenser. Crap! I'm not in the mood to rip the interior apart to get to the evaporator.

Then I thought I might be able to use the same test plate to vac check the evaporator. No dice. The pattern was close enough, but the overall length and width of the plate wouldn't fit into a plastic shroud surrounding the evaporator flange. So, I spent some time and trimmed it to the shape you see below.

I vac'd it down and isolated it. It held! Whew. Dodged a huge bullet. Great Cab.

The low side port fitting is from O'Reilley. I found one fitting would screw on a 1/4" flare fitting. I threaded the plate for 1/4" NPT. The whole mess got thread sealant. The plate seals to the condenser or evaporator flange using the OEM seals.

pgamboa · May 1, 2017

I wish I was more mechanically inclined. LOL. The part of this post I understood... "Great Cab" and "O'Reilley"

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Spurshot · May 2, 2017

This is the flange on the firewall where the evaporator lines hook up.

My adapter with the test port.

The test adapter installed and hooked to the gauge set.

thewhitestallion · May 3, 2017

This is my truck leaking... found this out last week. Just picked up a condenser from a dealer as they were the only one I could find in my area that actually had one. $400 for the part and two seals...

fondupot · May 3, 2017

What am I lookin at here @Spurshot?

dasimmon · May 3, 2017

I wish I was more mechanically inclined. LOL. The part of this post I understood... "Great Cab" and "O'Reilley"

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lmao! glad im not the only one

Spurshot · May 5, 2017

What am I lookin at here @Spurshot?

The adapter plate on the firewall with the blue hose and fitting is where the evaporator flange is. My adapter allows connecting my ac gauge set and therefore a vacuum pump, allowing me to leak check just the evaporator.

Update: vacuum held overnight. Time to reassemble the truck, charge and get back on the road.

http://s26.photobucket.com/user/roaniecowpony/media/Truck/20170501_193458_zps0c2kmtw8.jpg.html

fondupot · May 5, 2017

The adapter plate on the firewall with the blue hose and fitting is where the evaporator flange is. My adapter allows connecting my ac gauge set and therefore a vacuum pump, allowing me to leak check just the evaporator.

Update: vacuum held overnight. Time to reassemble the truck, charge and get back on the road.

http://s26.photobucket.com/user/roaniecowpony/media/Truck/20170501_193458_zps0c2kmtw8.jpg.html

I know some of these words.

This has to do with the vehicles air conditioning system?

Spurshot · May 5, 2017

I know some of these words.

This has to do with the vehicles air conditioning system?

That and nuclear power plants. LOL

Update:

I static charged the system (without running the engine/compressor) to the full capacity. I had to put the freon can in a pot of hot water while charging to get all of it in.

I put the truck back together and fired it up. With a 70f ambient temp, I was getting 45f duct outlet temp. Perfect.

Chev-mekanik · May 10, 2017

I guess I missed the part that explained why you had to dive into the A/C system to start with.

Spurshot · May 10, 2017

I guess I missed the part that explained why you had to dive into the A/C system to start with.

Yeah, looks like I jumped right into diagnosis and fix.

Short story is that it stopped cooling 6-8 weeks ago now. I put the gauges on it, pressures were very low, added freon, it leaked out in a couple days. The lines were suspected, but couldn't find leaks. Read a lot of line crack issues and noted the p/n was revised and a brace added. Bought all new lines. GFound compressor seal leak and replaced compressor, also with revised p/n rather than Change seal. Checked condenser and evaporator and charged it.

Sometime during all this I discovered my high side coupler was leaking, so I did all the testing and charging with the low side coupler. I charged by weight and check vent temperature was correct, but haven't checked pressures yet. My new couplers showed up last night.

Spurshot · May 11, 2017

New couplers for my gauges.

kstruckcountry · May 11, 2017

Probably going to jinx myself with this, but my 2006 AC hasn't been touched. Not terribly confidence inspiring that they can't build a pickup to hold freon after a couple years now.

That said, great diagnosis and fix. Wish I was more capable concerning AC.

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Spurshot · May 11, 2017

Probably going to jinx myself with this, but my 2006 AC hasn't been touched. Not terribly confidence inspiring that they can't build a pickup to hold freon after a couple years now.

That said, great diagnosis and fix. Wish I was more capable concerning AC.

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Agreed, my old el Camino went maybe 18 years before it needed service.

O_J_Simpson · May 11, 2017

Probably going to jinx myself with this, but my 2006 AC hasn't been touched. Not terribly confidence inspiring that they can't build a pickup to hold freon after a couple years now.

That said, great diagnosis and fix. Wish I was more capable concerning AC.

Sent from my SM-G920V using Tapatalk

The GMT-800's had one of the best AC systems GM ever produced. The evaporator, compressor and condenser were over sized because of 134a and there was no concern to save fuel with a smaller compressor. They last forever and have no issue blowing at 40F in 100F weather.