Automotive Air Conditioning Information Forum (Archives)

Provided by

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

1972 Volvo 145S custom/reinstallation

KGHN on Wed August 27, 2008 2:38 PM User is offline

Year: 1972
Make: Volvo
Model: 145S station wagon
Engine Size: 2L
Refrigerant Type: R406A
Country of Origin: United States

Here's information we spent hours figuring out, and were successful. I post my notes to help others that might need it. This project was done in July 2008.

Our 1972 Volvo 145S station wagon originally had dealer-installed FrigiKing air conditioning. When it became non-functional about 20 years ago, we pulled the entire system out. Here's my description of how we reinstalled the air conditioning.

After much research, we decided on R406A blend refrigerant (mostly R22), aka Autofrost. EPA certification is required for purchase of R406A. Nick passed the required EPA 609 certification test easily. (Find good practice software and convenient testing at
ATC Specialists,, sells a convenient R406A kit, and the website has lots of information. The kit contains the EPA-required special fittings that cap R12 ports, but not the adapters that mate with them for maintenance. We used the new R12-fitting tap equipment that comes in the kit with the compressor's R12 ports, then ordered the maintenance adapters separately by phone from the same people against future need.
R406A is fine with mineral oil lubricant, which does not grab water like R134a's lubricants do. We used Ford YN9 light mineral oil, a viscosity 300 mineral oil mentioned in several pages we found. In hindsight, I believe we could have used the standard viscosity 500 or 525 mineral oil with this compressor without a problem. (The Ford YN9 is no longer available except as left over "new old stock".)

The original compressor was a York F209R-20367, a 2-cylinder model which vibrated a lot. (See for info on York model designations.) It is listed as a 9 cu in, but our measurements revealed 1-13/16" bore, 1-9/16" stroke x 2 = 8.06 cu in. With our pulley size, that should have pushed 6.25 cu ft/min at 1000RPM.
The Swedish Iron book recommends a Sanden/Sankyo rotary type compressor. We bought a SD507 model S9173, 7 cu in with R12 flare fitting type hose ports and a slightly smaller pulley, that pushes about the same volume per engine rotation. (In hindsight, we think the 5 cu in SD505 would have also been fine; the SD507 provides plenty of compression plenty fast. We are planning to use a smaller, lighter 505 in our Volvo 1800ES when we do a new A/C system there.) We had to drain and flush the R-134a-compatible PAG oil out of the new compressor before using it.
Arizona Mobile Air ( sells a #5033 York-mount-to-Sanden adapter plate, well worth the $40 price.

We bought a "universal" receiver-drier with a sightglass and dessicant type XH9, #085737-00 from Arizona Mobile Air, Their techs were very helpful to us with phone advice.
We had in our parts pile an unused non-parallel-type condenser from JC Whitney.
We had a genuine used original-style Volvo-FrigiKing dash unit (evaporator, expansion valve, fan.) The dash unit needed a new thermostat switch, Ranco A10-6494 = AG A/C 220-214 = NAPA 207500. Our testing was confused by the new thermostat switch knob's control rotation working backwards from the old one, but it was in all other respects an exact replacement.

We bought custom "barrier type" hoses from Ray's Auto Air & Heat ( A/C hoses come in 4 sizes, designated #6, #8, #10, and #12. The website lets you easily specify hose size, fitting type, and rotation, and they shipped the day we ordered. Our system needed two #6s, in lengths 54" (condenser->receiver-drier) and 30" (receiver-drier->dash unit expansion valve), one #8 42" (compressor->condenser), and one #10 60" (dash unit evaporator->compressor). (Check your components for whether you need O-ring or flare fittings.)
The hoses came with HNBR (light green) O-rings. Per advice from the Autofrost site, we replaced those with neoprene (blue) ones out of an assortment box from Four Seasons (Murray) available at our local auto parts store.

We bought insulating tape to wrap the evaporator outlet pipe, #40-32400 from

Venturi vacuum pumps are cheap, but our research determined they are inadequate to remove all the moisture from the system at our altitude (over 5000ft.) We bought a used 5cfm vacuum pump, fast and effective. We bought a used R-12 type gauge set. (We also bought a used recovery machine, but haven't needed it yet.) We used mineral spirits and our air compressor to flush the old FrigiKing expansion valve/evaporator dash unit.

We put 5.5 liquid oz mineral oil in the compressor, and 2 oz in the receiver-drier before hooking everything up. We then evacuated to vacuum, let it sit overnight, checked the vacuum was holding, and charged the system with refrigerant.
We charged with (3) 9.6oz R406A cans (=28.8oz.) (The Autofrost kit comes with two 9.6oz cans, a charging hose that attaches to the gauge set, a can-top tap, and the EPA-mandated special R406A compressor port adapters and ID sticker.) When the system is running, there are a few bubbles swimming by in the sightglass of the receiver-drier, an indicator that we are safely on the preferable shy side of a "full" charge.
The system runs beautifully cold.

Followup: We drove from Montana to North Carolina and back in mid-July. With the windows up, we got better gas mileage and had a quieter ride. The A/C was very pleasant, and made the journey a less fatiguing and therefore safer trip.
The engine was running hotter than usual in town and summer heat while the A/C was on, so we bought an electric fan with a temperature sensor that inserts into the condensor. This works well. Also, a slightly higher unloaded idle has been required to prevent stalls at stop signs when the A/C is running.

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.