Budget underhood AC retrofit.

My 74 Duster has Factory AC, but when I bought the car in pieces, there were no underhood parts included. I decided to install what I believe to be better, more readily available parts underhood as an upgrade to the system.

I used a compressor, brackets and the suction and discharge hoses sourced from a donor 1985 Dodge Truck. This may or may not be the best compressor choice, but I have always had great service from the C171 compressors and I knew I could source the compressor and brackets to fit my engine for free. I chose not to use the #6 hoses from the outlet of the condensor or the receiver/dryer from the donor truck since they had flat plate sealing flanges that I was not too keen on. I would have reused the hoses themselves but I could not easily source the appropriate fittings locally like I could with the bead lock hose. The donor truck used reduced bead lock hose for this line. My original plan was to use the condensor from the donor truck too but It was slightly too large and it also connected with the flat plate fittings. As well, the older pass through style condensers are not suited for modern refrigerants from what I understand.

So here is how it went so far, the compressor bolted on like it did on the truck. I should mention that not all aftermarket intakes will work with the factory AC brackets. I had to change my Edelbrock LD4B for an Edelbrock Performer 318/360 because of the offset thermostat housing on the performer. The Edelbrock Torker 2 also will work in a higher horsepower application. When I add my TBI in the future, I will likely go to a Torker 2 then.

It does require the crank pulley and water pump pulley from the donor truck as well. I also used the factory clutch fan from the donor truck which fit perfectly with the stock 26” rad (recored to 3 core) and factory shroud. It cools quite well. In order to run the 2 belts on the compressor, fan and alternator like it was originally, I will have to replace the alternator pulley with a 2 groove pulley. It is currently running with 1. The power steering side stays the same. There is an extra v-groove on the crank pulley for a second belt to the power steering pump but I could find no reason for it so I never added a second belt.

The suction hose is #12 bead lock hose. I used the factory fitting at the compressor and just cut the other fitting off and crimped on a #12 Female O-ring to #12 bead lock straight hose fitting for it to attach to the outlet of the factory Duster evaporator. There is plenty of hose for this. The discharge hose is #8 bead lock hose. I used the factory fitting at the compressor and will just cut the other fitting off and crimp on a #8 female O-ring to #8 bead lock straight or 45 degree hose fitting to connect to my aftermarket condenser. There is barely enough hose on this one (but there is enough) and I may have to modify the Rad support to allow for the fitting to connect to the condenser. I could adjust the mounting of the condenser to avoid this but I feel that the slight cut to the rad support is the best solution. The final decision will be made when I do the hook ups. Remember, if you choose the 45 degree fitting, it must be clocked correctly so no twist is introduced into the hose.

I mounted the receiver/dryer in the area formerly home to the charcoal canister. I will use a #6 female o-ring to #6 bead lock hose 90 deg. fitting at the outlet of the condenser and the same #6 female o-ring to #6 bead lock hose 90 deg. fitting at the inlet of the receiver/dryer. New #6 bead lock hose will be used in this section. At the outlet of the receiver/dryer another #6 female o-ring to #6 bead lock hose 90 deg. fitting will be used on another piece of new hose. On the other end of the new hose a #6 female o-ring to #6 bead lock hose 45 deg. Fitting will connect to the expansion valve.

The expansion valve connects directly to the #8 Female O-ring inlet on the factory evaporator. Remember the fittings must be clocked correctly so no twist is introduced into the hose.

The receiver/dryer I chose has a port for a pressure switch that controls both low pressure cut out and high pressure cycling of the compressor. I ran the factory AC clutch wire from the Duster Harness to the pressure switch then to the clutch. The factory Dodge truck service ports will be retained with adapters for modern refrigerant screwed on to them.

When I an done, I will add pictures of compressor mounting, hose and wiring routing, condenser mounting and anything else I can think of that may help someone else learn from my mistakes. I have no prior AC experience and I am learning this all as I do this job. Some things could be done better I’m sure but this is how I chose to do it given the information I could find. I ordered a few wrong parts along the way but that’s part of the learning process. I hope others can benefit from my experiences!

If anyone wants to share experience or help me do this better, please do. The one part I am still not 100% sure on is the connections to the compressor. I did find some C171 inlet and outlet adapter fittings but they appear to be no longer available at any of the suppliers I contacted that showed them in their catalogs. I know lots are going to say I should have used a Sanden compressor, but I am trying this in an effort to keep costs down.
Cley

Parts list
A) Expansion Valve with #6 Male insert O-ring inlet and #8 Male insert o-ring outlet(NAPA Part# A17191)
B) Stock Evaporator
C) C171 compressor from 1985 Dodge truck
D) Condensor with #8 Male insert O-ring inlet and #6 male insert o-ring outlet (Climaparts Part# CFNP1426)
E) Reciever/dryer with #6 Male insert O-ring inlet and outlet (NAPA Part# NTC A7959)
F) Pressure cycling switch (NAPA Part# A8381)
1. Suction hose from 1985 Dodge truck
2. #12 female O-ring to #12 bead lock hose crimp fitting (Part# BL 1304)
3. Compressor fitting seal kit (NAPA Part# NTC A 12561)
4. Discharge hose from 1985 Dodge truck
5. #8 female O-ring to #8 bead lock hose crimp fitting (Fitting Part# BL 1302(straight) BL 1312(45 deg))
6. #6 female O-ring to #6 bead lock hose 90 deg. crimp fitting (Part# BL 1321)
7. #6 bead lock hose
8. #6 female O-ring to #6 bead lock hose 90 deg. crimp fitting (Part# BL 1321)
9. #6 female O-ring to #6 bead lock hose 90 deg. crimp fitting (Part# BL 1321)
10. #6 bead lock hose
11. #6 female O-ring to #6 bead lock hose 45 deg. crimp fitting (Part# BL 1311)
12. Mounting brackets and all related fasteners from 1985 Dodge truck
13. Crank pulley from 1985 Dodge truck
14. Water pump pulley from 1985 Dodge truck
15. Clutch fan from 1985 Dodge truck.
16. 2 groove alternator pulley (Part# not yet found)
17. Alternator belts for 1985 Dodge truck with air conditioning (NAPA Part# 25-7570 – 13-32x57 5/8)
• All NAPA part #s are from NAPA Canada website and do differ from U.S. NAPA site. When I gave US part numbers to my Canadian Napa guy, he had to cross reference them but it seemed to be no problem.
• All fitting part #s are from APCOAir catalog downloaded online. I sourced these fittings from NAPA as well, but they are available on E-bay and I realize that without my discount through work, NAPA isn’t always the place to buy from. I get my parts for about ½ of list.
• Climaparts condenser ordered on E-bay because it was 1/3rd the cost of picking it up locally and it appears to be the same unit that Bouchillon Performance includes in their underhood kits.

I can't help you doing this any better for your application. For me, I am adding AC to my slant 65 Dart wagon and am using all the factory under dash components, factory condenser, and factory horizontal drier rebuilt by Classic Air. I will be using a Sanden compressor mounted to 79 Aspen/Volare AC brackets. I will be sending the hoses to Classic Air so they can be replaced with 134-compatible hoses. The hose fittings going to the connections on the firewall and condenser will remain the same. I will have them to not install any fittings to the compressor side of the hoses plus leave them a little longer than original so new fittings suitable for the Sanden can be used and the hoses fitted to a suitable length. Electrically it will be as per original 65.

I wish to heck you would post some photos of this. I considered similar, but found a complete underhood aftermarket setup for an LA from a member here. What do you mean "beadlock" hose is that intended for AC use?

Beadlock is a type of AC hose. The factory hoses off the compressor on the donor truck are beadlock hose. I only have the condenser and drier in so far. If I can get my buddy with the crimper to come over this weekend I'll post pics of the whole thing.

It's hot as he'll (for Canada anyway) right now so i am looking to get this done ASAP.
Cley

Will you post pictures of this

I'll do a full detailed post ASAP. Nut my buddy with the A.C. tools booted his old lady out and I won't push him for help just now. I may buy the tools myself but I'm gonna give him a little more time. He mentioned it last week so maybe we can get at it soon. If I bait him with his favorite potato water (Vodka) that may help too!
Cley

65 Dartman said:

... slant 65 Dart wagon ... Sanden compressor mounted to 79 Aspen/Volare AC brackets. ...

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I hope you read the long post on "AC options" in the slant forum. The Volare brackets will just barely clear the battery (~1/2") in an early A, so could puncture the side if the engine shakes. I cut the corner off for another 1/2" clearance (but ended up making a custom Sanden bracket). Some new cars use much thinner batteries, which might be an option (or trunk-mounted). Re hoses, you can re-rubber them yourself. If you don't have/buy a Master-Cool crimper, you can use Oeticker stepless ear clamps for a slick look. Even screw hose clamps would work, since used on after-market kits of the day, but look ugly. If you do screw, use Breeze smooth clamps.

BillGrissom said:

I hope you read the long post on "AC options" in the slant forum. The Volare brackets will just barely clear the battery (~1/2") in an early A, so could puncture the side if the engine shakes. . . . . Re hoses, you can re-rubber them yourself.

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I saw that post. Awhile ago I mocked up the 79/80 Volare/Aspen brackets and my brand new Sanden cmpressor on a slant that was on the stand with several different manifolds and the brackets appeared to have plenty of room. Once everything is installed in the engine compartment we'll see where everything lies. Moving the battery to the rear is not an option in the wagon (at least for me). A friend and I have already sent our early hoses to Classic Air to have them done. They will also restore the fittings so for the price, I can't complain. I will have to consider doing them myself as I plan on adding AC to the 47 Dodge rod I will be doing.

With spring right around the corner, I am getting back to my AC retrofit. I think I have everything I need other than some short lengths of #6 hose and the crimper. Here is an underhood pic with the compressor and stock truck hoses before I get the new ends crimped on.

Cley

I'd be interested in this business of converting from what you are calling the "flat plate" fittings. Just how did you do this?

I used a totally different condenser and drier that got rid of these completely. Originally I thought I had to adapt to the steel tube coming off the flat plates but afterwards I found that the old style condenser out of the truck was a poor design for modern refrigerant and it was also too large to fit without a lot of modifications. Soon I will document all I have learned during this little **** show I created for myself.

Cley

I understand the C-171 is a good compressor, and comparable to a Sanden in size and efficiency. The funky fittings are a downside, but as long as you can get the seals (gaskets?) they look fine. It would be easy to cut off the ferrules to re-hose them. I did that on my M-B (funky metric O-ring fittings), which were Coll-O-Crimp type so had to also cut it off the tube. A hacksaw or cut-off wheel and prying w/ screwdrivers and pliers peels it off. I have a Master-Cool AC crimper, so used that. I used mostly "reduced barrier" hose and found that some standard ferrules and dies fit (#8 works on #10 reduced and such, forgot), though they do sell special "reduced dies" for $$. Ferrules look factory, but aren't necessary. Oeticker clamps or screw clamps also work. Use "barrier" hose, which has an inner liner for less leakage and better chemical resistance. Newer parallel-flow condensers are claimed 30% more efficient, but you can't clean them like the older 1-tube condensers, so change if your compressor scatters debris. R-134A works poorer than R-12, so needs help. But, it is being discontinued so I wouldn't use it. I think PAO 68 oil is best for any refrigerant, since it doesn't absorb moisture and better stays in the compressor. I use that oil and Duracool refrigerant in all my vehicles (1996 and 2002 after compressors failed).

I finally got a chance to borrow my buddy’s AC hose crimper this weekend. I got all my hoses made and only ran into one snag. The expansion valve I found turned out to be incorrect. It has the correct #8 end to attach to the evaporator, but the #6 end that would attach to the drier outlet hose is not correct. The pipe and o-ring part appears to be right but the nut does not fit the threads. So, back to the drawing board searching for parts on that one.

The original #12 hose from the truck works very well with the new end crimped on. I could have definitely shortened it a little but it is fine how it is in my opinion. Not show car quality, but that is not what I was going for.



I was worried about the #8 hose on the outlet of the compressor being too short, but it turned out that I had to cut an additional 1 ½” off of it to make it work with the new compression fitting. I’m pretty mad at myself about the hole I hacked into the rad support to allow room for the fitting (see pictures), as it could have been way smaller and neater, so I guess I’ll have to figure a way to clean it up a bit. Again, not a show car but not a hack job either.





The #6 line from the bottom of the condensor to the drier worked out really well. If I had it to do again, I would look at putting the drier on the front side of the rad support, just to declutter the engine bay a little. It will work like it is though.





Now here’s the last piece to the puzzle. The damn expansion valve. Once I find a suitable valve, I’ll update the parts list on the first post of this to include the correct part number.



So what did I learn so far?

• The Mastercool crimper I borrowed is a nice, easy to use tool that should make good long lasting crimps. My buddy has been using it for a few years now.
  
  
• The hoses could be routed for a much cleaner install, but that would add additional cost since I never had to purchase any #12 or #8 hose the way I did it.
  
  
• The #6 hose is difficult to purchase in short pieces, at least around here, so I would possibly look at using hard line like the factory did next time.
  
  
• With a lot of the research done, this is a relatively easy retrofit using easy to find junk yard parts and brackets. I maybe would not have to, but I think I’ll put on a reman compressor before charging the system up.
  

Here are a couple more random pictures I took during this weekend’s portion of the install.

Cley

Are there any A.C. gurus on here that can help me find an expansion valve? I have found all my parts so far in Google searches, but my expansion valve is proving a bit harder. I have bought 3 so far and none have been correct. It needs to be suitable for 1.5 ton with a #6 Male insert o-rng inlet and a #8 Male insert o ring outlet.
What I could find online showed the original piece being 1.5 ton so that's where I got that from.
I'd appreciate any help as time is running out before I should be driving it!
Cley

Four Seasons® 39150 - A/C Expansion Valve
Looks close but #5 by #8
Are you sure #6 by #8 is correct?

I'm pretty sure the one I have that is almost correct is #5 x #8. Even though it says #6x#8 in Napa's online catalog. I'l look on that Four Seasons website though.
Cley

Well I got the correct expansion valve finally! #6MIO inlet, #8MIO outlet, internally regulated. Napa part number A8262. I also put on a Reman compressor because once I finally get this working I don' need to pump it down to chance a damn compressor! Now I just need to get it charged up and test it out.

One thing I am not sure of is what to do with the brass tube coming out of the top of the expansion valve. I'm sure it' a temperature sensor but I'm not sure if it senses under hood temp for some reason or if it needs to be wrapped around the compressor suction line. Any Body know?

Cley

My 1969 Dart had factory air and a similar-looking expansion valve. The thin copper tube is a "gas temperature sensor". It slid into an internal "temperature well" tube that was inside one of the refrigerant tubes, which I am guessing would have been downstream of the valve. The purpose is to proportion the flow to maintain a constant temperature in the evaporator. If it goes above the boiling point, the valve opens to let in more refrigerant. That works better than the fixed orifice which GM cars used thru the 1970's. Modern expansion valves are the same, but the temp sensor is integral with the valve. The problem with using them is that all in my cars attach to flat blocks, w/ an O-ring face seal, so might be hard to adapt. Those using an under-dash knee-knocker climate unit need not fool w/ an expansion valve since they are built into those.

I'm pretty sure the truck system I got the under hood components from had a fixed orifice too. There is no temperature well for me to install it into so I guess I'll try wrapping it around the metal part of the evaporator outlet fitting and then insulate it as beast I can. Thanks for the advice. It will be a couple weeks before I get it charged and then I can confirm whether all this fooling around was worth it.
Cley

89on35s said:

Well I got the correct expansion valve finally! #6MIO inlet, #8MIO outlet, internally regulated. Napa part number A8262. I also put on a Reman compressor because once I finally get this working I don' need to pump it down to chance a damn compressor! Now I just need to get it charged up and test it out.

One thing I am not sure of is what to do with the brass tube coming out of the top of the expansion valve. I'm sure it' a temperature sensor but I'm not sure if it senses under hood temp for some reason or if it needs to be wrapped around the compressor suction line. Any Body know?

Cley
View attachment 1715162299

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There's a 73 Dodge service manual (came from the guys on here) for free download over at MyMopar if you don't have one.

Start with page 24-47 in the 73 manual...........They are showing the 73 has a well for the sensor tube in the suction line. Normally you want to wrap that and seal it with insulating tape to keep it as close to the suction line temp as possible. "Engine bay heat" is not your friend

Gotta tell you all about a 73 Dart Swinger I bought new in Charleston South Carolina. Took it to Montgomery Wards and they put in a really nice underdash A/C for 49.95 installed! R12 and cold as you could stand. Wish I could find that car now. Traded in at a dealer in Salem Oregon around 1979.

67Dart273 said:

There's a 73 Dodge service manual (came from the guys on here) for free download over at MyMopar if you don't have one.

Start with page 24-47 in the 73 manual...........They are showing the 73 has a well for the sensor tube in the suction line. Normally you want to wrap that and seal it with insulating tape to keep it as close to the suction line temp as possible. "Engine bay heat" is not your friend

View attachment 1715162703

Click to expand...

Thanks for the pic! I have that manual and I looked at that. The expansion valve I am using is internally regulated (just 1 temp sensor out of the top) and I don't have the thermo well on my suction line so hopefully I will be able to create the same effect by wrapping it around the outside of the suction hose fitting and insulating it as well as I can. I will report back once I try it.

Cley

I wrapped the heat sensing tube from the expansion valve around the metal part of the compression fitting that attaches to the outlet of the evaporator. I first wrapped it with a fibrous insulation material, then an aluminum foil reflective tape, then good quality electrical tape for protection. I still have not got it charged but when I do, I'll report back on how it works.

Cley

Success! I got my A.C. system charged yesterday. I have not got it tested on a real warm day in traffic yet, but it holds a charge and blows nice and cold. After all the time I put into this, mostly research as I had no prior knowledge on A.C. systems, my cruise time can be more comfortable.
Cley

After driving 60 miles to work today in 30 degrees C it performed as expected. Never got any hotter on the Temp gauge! The car is super comfortable now and I am happy I got the AC working.

Cley