Double Doofus - Air conditioning on a 69 Fury III vert

[3175375]

Yesterday, I took a stab at recharging the air conditioning on my 69 Fury III vert - Shamu.
It had about 25 psi of pressure at rest. I hooked up the line gauges (per the markings on the compressor- doofus #2 - I’ll describe #1 later) and proceeded to add some Freon (R-12).
I noticed that the pressures appeared to be backwards - that I was seeing higher pressures on the low side vs. the high side.
I swapped the blue and red hoses and the pressures looked more reasonable - figuring that I had incorrectly attached them - in haste.
Pressures started rising and the compressor started kicking in. I added more and the compressor finally got to where it was running continuously, but the high side pressure was really high, nearly 350 psi. I proceeded to add more as I thought that the system would settle down - boom! The suction (low) side hose blew, spewing oil all over the inner fender well on the passenger side.

I regrouped and inspected the hoses. I learned that the system was connected to the compressor backwards! This floored me as the previous owner purposely attached them (beautifully) bass-ackwards! (I suspect ignorantly - doofus #1).

So after chatting with my cousin, who runs a heating and cooling company, I indeed determined that the lines were attached backwards. The scroll compressor worked, but I learned that it would not have cooled itself properly as the compressor sloshes the oil inside it when rotating correctly and wouldn’t when running backwards.

My cousin told me about a shop in Sioux Falls that will make up custom hoses (I can’t just swap the compressor ends as they are different sizes).
I will remove both side (high and low) and take them to the shop to be remade correctly.

I think that they can reterminate the low side hose on the compressor side of the drier, but I will discuss with the technician that will do the work.

More to come…

 

[3175375]

Yesterday, I took a stab at recharging the air conditioning on my 69 Fury III vert - Shamu.
It had about 25 psi of pressure at rest. I hooked up the line gauges (per the markings on the compressor- doofus #2 - I’ll describe #1 later) and proceeded to add some Freon (R-12).
I noticed that the pressures appeared to be backwards - that I was seeing higher pressures on the low side vs. the high side.
I swapped the blue and red hoses and the pressures looked more reasonable - figuring that I had incorrectly attached them - in haste.
Pressures started rising and the compressor started kicking in. I added more and the compressor finally got to where it was running continuously, but the high side pressure was really high, nearly 350 psi. I proceeded to add more as I thought that the system would settle down - boom! The suction (low) side hose blew, spewing oil all over the inner fender well on the passenger side.

I regrouped and inspected the hoses. I learned that the system was connected to the compressor backwards! This floored me as the previous owner purposely attached them (beautifully) bass-ackwards! (I suspect ignorantly - doofus #1).

So after chatting with my cousin, who runs a heating and cooling company, I indeed determined that the lines were attached backwards. The scroll compressor worked, but I learned that it would not have cooled itself properly as the compressor sloshes the oil inside it when rotating correctly and wouldn’t when running backwards.

My cousin told me about a shop in Sioux Falls that will make up custom hoses (I can’t just swap the compressor ends as they are different sizes).
I will remove both side (high and low) and take them to the shop to be remade correctly.

I think that they can reterminate the low side hose on the compressor side of the drier, but I will discuss with the technician that will do the work.

More to come…View attachment 527618View attachment 527619View attachment 527620

Additionally, compressor is a Sanden 508 chinesium knock off.

 

[Mr C]

Thanks for posting this...things for us hobbyists to look for when these cars have been converted/ already messed with. The original compressor would have been an RV2.

 

[TxDon]

Looks and sounds strange - you should not have been able to switch the high and low pressure gauge hoses, the disconnects are different sizes. It also looks like both hookups on the compressor are the same size, they should also be different.

 

[3175375]

Looks and sounds strange - you should not have been able to switch the high and low pressure gauge hoses, the disconnects are different sizes. It also looks like both hookups on the compressor are the same size, they should also be different.

View attachment 527651

The compressor fittings are different sizes and from what is there, the previous owner had the ends for the scroll compressor added incorrectly from the RV2 fittings!

 

[Davea Lux]

The compressor fittings are different sizes and from what is there, the previous owner had the ends for the scroll compressor added incorrectly from the RV2 fittings!

I hope you tested the remaining refrigerant in the system to see what it was charged with. RV-2 compressors from the factory had R-12 in them. Nearly all of the replacement scroll compressors would have been charged with R-134a. These two types of refrigerant do not play well together and you would be headed for major problems down the line if that is the case. Since the system is now discharged due to the blown out line, you should have the system flushed by a competent shop to have the contaminated oil removed from the system.. The filter dryer should also be replaced and the system then charged with fresh oil that is appropriate for your choice of refrigerant after the system has been evacuated. You should also discard the R-12 hose fittings as they have barbed anchors to hold the hoses, these often punch holes in the inner membrane of the rubber hose causing the smaller R-134a molecule to leak out.

Dave

 

[3175375]

I hope you tested the remaining refrigerant in the system to see what it was charged with. RV-2 compressors from the factory had R-12 in them. Nearly all of the replacement scroll compressors would have been charged with R-134a. These two types of refrigerant do not play well together and you would be headed for major problems down the line if that is the case. Since the system is now discharged due to the blown out line, you should have the system flushed by a competent shop to have the contaminated oil removed from the system.. The filter dryer should also be replaced and the system then charged with fresh oil that is appropriate for your choice of refrigerant after the system has been evacuated.

Dave

Verified that the compressor had R-12 in it. Previous owner stated it and compressor is marked with R-12.
Compressor is from the company ‘New’, made in China. This company re-emerged as ‘UAC’ with the same logo. I am certain that this compressor is old enough to be an R-12 unit.

 

[commando1]

Wow. You really opened Pandaras box with this one.
I think you should start back at square 1 and buy the proper model genuine Sanden. We have threads here about Sanden compressors.

 

[3175375]

Wow. You really opened Pandaras box with this one.
I think you should start back at square 1 and buy the proper model genuine Sanden. We have threads here about Sanden compressors.

I am going to get a pair of hoses made to swap the discharge and suction sides, as well as repair the portion of the suction side further upstream of the adapters I have made.

My gut is telling me that the previous owner installed them bass-ackwards and never charged the system enough to get it to operate.
My cousin, who owns an HVAC business told me that he’d share some horror/doofus stories with me and suggested the repair shop that I am visiting tomorrow morning as one who is extremely knowledgeable on these systems.
If push comes to shove, I’ll replace the compressor.

 

[3175375]

Met with the AC shop and they 1) understand the problem and 2) will likely repair it and have it done today.
I am going to replace the expansion valve while I am at it.

More to come…

 

[3175375]

Picked up the hoses and supplies this evening.
Tomorrow it’ll get back together…

 

[3175375]

Hoses installed and pulled a vacuum.
It’s held for over an hour at 30” of Mercury.

Next steps are:

1) Add 1 oz of Johnson’s Ester oil

2) pull vacuum again for 45 minutes

3) add R-12 and verify pressures and temperatures

 

[3175375]

Update 4/26/22:

I got everything connected and charged the system. Had a leak on the high side hose that I had adapted to be correct (it was in a braze that the shop did).
During this work, I verified that the system was working as even though there was refrigerant pissing out the pinhole, the low side (suction) had ice forming on the hose near the compressor and there was cool air coming out of the dash registers.

Yesterday, I took it back to the place that I had the work done and they made a new hose, 2” shorter - it was pushing the hose to the condenser into the inner fender well). The owner of the company also gave me a 12 oz can of R-12 for my trouble.
I will reassemble the equipment, add a bit of oil before pulling a vacuum and recharge it tomorrow.
Good shop that makes it mistakes right.

 

[3175375]

Looks like there’s more issues in the system.
High side pressures got excessive and I am going to remove the refrigerant and inspect the expansion valve and drier.
I saw frost developing on the low side on initial charge, but the expansion valve wasn’t cold.

I need to think about this some more and sort this out.

More to come…

 

[commando1]

Looks like there’s more issues in the system.
High side pressures got excessive and I am going to remove the refrigerant and inspect the expansion valve and drier.
I saw frost developing on the low side on initial charge, but the expansion valve wasn’t cold.

I need to think about this some more and sort this out.

More to come…

Wow. You really opened Pandaras box with this one.
I think you should start back at square 1 and buy the proper model genuine Sanden. We have threads here about Sanden compressors.

 

[3175375]

I am unsure of the compressor being defective.
I am thinking that the expansion valve is stuck.
Continuing to think about this and I am awaiting a call from my cousin, who runs an HVAC business.

 

[3175375]

Added some liquid R-12 and high side pressure was around 400-425 with low side at about 0.
Confirmation of a stuck expansion valve.
I’ll suck the refrigerant out and replace the expansion valve and possibly the receiver/drier. Parts due by Sunday, so it’ll have to be after I have my tailpipe scoped (colonoscopy) on Monday. 8^O

 

[3175375]

Yesterday, my cousin came over, bringing a recovery machine.
We pulled 2.5 pounds of R-12 from the system.
He’s quite sure that the expansion valve is stuck closed, which would explain why the system was not obtaining positive pressures on the low side.
He also recommended replacing the receiver/drier while replacing the expansion valve.
I also ordered a replacement mode switch as I couldn’t select defrost or heat on the one in the car. The corner of the mode switch is cracked and I may rebuild it on another day.

I should have the expansion valve and receiver/drier by tomorrow. Once I replace them, I’ll evaluate the system and recharge it with 2.25 pounds of refrigerant, and top it off until the bubbles go away in the sight glass of the receiver/drier and see how it performs.

 

[PeugFra]

I can't help myself from making this comment. I admire the workmanship and dedication that's going into this problem, and I don't want to distract from the subject, but I thought the doofus part was about having airco in a convertible anyway. Lots of heating should be enough.

So ... what's the proportion of verts with airco? I see this particular one is from SoCal.

 

[Davea Lux]

Yesterday, my cousin came over, bringing a recovery machine.
We pulled 2.5 pounds of R-12 from the system.
He’s quite sure that the expansion valve is stuck closed, which would explain why the system was not obtaining positive pressures on the low side.
He also recommended replacing the receiver/drier while replacing the expansion valve.
I also ordered a replacement mode switch as I couldn’t select defrost or heat on the one in the car. The corner of the mode switch is cracked and I may rebuild it on another day.

I should have the expansion valve and receiver/drier by tomorrow. Once I replace them, I’ll evaluate the system and recharge it with 2.25 pounds of refrigerant, and top it off until the bubbles go away in the sight glass of the receiver/drier and see how it performs.
View attachment 528419View attachment 528421View attachment 528422View attachment 528423

The factory R-12 system had about 12oz of oil installed in it. After repeated evacuations, you have lost a significant amount of oil due to evaporation. Secondly, anytime a receiver/dryer is replaced, it will have about 6oz of oil trapped in it. I would suggest adding at least 6oz of oil to compensate for this loss. If you can find a spec sheet for the replacement scroll compressor, it might have the amount of oil listed for the conversion process. Most modern scroll compressors have a 6oz minimum.

Dave