Im not concerned with all the legal nonsense and I do my own work, I can recover a/c using my equipment anyway, and even if I didn't, venting a hydrocarbon refrigerant is no different than starting your propane grill. I don't want to use freeze12, I'm asking about r12a which is a hydrocarbon refrigerant compatible with r12 systems, it has nothing but high purity butane and propane in it. The good thing about HC refrigerants is they don't need higher pressures like 134, they dont eat old r12 o rings, they are compatible with all oils, they cool like r12 does, and they don't need barrier hose. The problem is redtek's site states that you cannot use with butyl rubber hoses. I want to know if our cars have butyl rubber hoses or not.

Can you provide a credible link that states that? You can buy alternative blend refrigerants, yet it is illegal to service it? Something not jiving here.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Per https://en.m.wikipedia.org/wiki/Butyl_rubber#Uses

Here are all the uses of Butyl rubber, AC hose is not one of them:

"Uses

Fuel and lubricant additive
Polyisobutylene can be reacted with maleic anhydride to make polyisobutenylsuccinic anhydride (PIBSA), which can then be converted into polyisobutenylsuccinimides (PIBSI's)by reacting it with various amines. These derivatives have interesting properties when used as an additive in lubricating oils and motor fuels. Polyisobutylene added in small amounts to the lubricating oils used in machining results in a significant reduction in the generation of oil mist and thus reduces the operator's inhalation of oil mist.[3] It is also used to clean up waterborne oil spills as part of the commercial product Elastol. When added to crude oil it increases the oil's viscoelasticity when pulled, causing the oil to resist breakup when it is vacuumed from the surface of the water.

As a fuel additive, polyisobutylene has detergent properties. When added to diesel fuel, it resists fouling of fuel injectors, leading to reduced hydrocarbon and particulate emissions.[4] It is blended with other detergents and additives to make a "detergent package" that is added to gasoline and diesel fuel to resist buildup of deposits and engine knock.[5]

Polyisobutylene is used in some formulations as a thickening agent.

Explosives
Polyisobutylene is often used by the explosives industry as a binding agent in plastic explosives such as C-4.[6] Polyisobutylene binder is used because it makes the explosive more insensitive to premature detonation as well as making it easier to handle and mold.

Sporting equipment
Butyl rubber is used for the bladders in sporting balls (e.g. Rugby balls, footballs, basketballs, netballs) to provide a tough, airtight inner compartment.

Damp proofing and roof repair
Butyl rubber sealant is used for damp proofing, rubber roof repair and for maintenance of roof membranes (especially around the edges). It is important[citation needed] to have the roof membrane fixed, as a lot of fixtures (i.e., air conditioner vents, plumbing and other pipes, etc.) can considerably loosen it.

Rubber roofing typically refers to a specific type of roofing materials that are made of ethylene propylene diene monomers (EPDM rubber). It is crucial to the integrity of such roofs to avoid using harsh abrasive materials and petroleum-based solvents for their maintenance.

Polyester fabric laminated to butyl rubber binder provides a single-sided waterproof tape that can be used on metal, PVC, and cement joints. It is used for repairing and waterproofing metal roofs.

Gas masks and chemical agent protection
Butyl rubber is one of the most robust elastomers when subjected to chemical warfare agents and decontamination materials. It is a harder and less porous material than other elastomers, such as natural rubber or silicone, but still has enough elasticity to form an airtight seal. While butyl rubber will break down when exposed to agents such as NH3 (ammonia) or certain solvents, it breaks down more slowly than comparable elastomers. It is therefore used to create seals in gas masks and other protective clothing.

Pharmaceutical Stoppers
Butyl and Bromobutyl rubber are commonly used for manufacturing rubber stoppers used for sealing medicine vials and bottles.[7]

Chewing gum
Most modern chewing gum uses food-grade butyl rubber as the central gum base, which contributes not only the gum's elasticity but an obstinate, sticky quality which has led some municipalities to propose taxation to cover costs of its removal.[8]

Tires
Butyl rubber and halogenated rubber are used for the innerliner that holds the air in the tire."

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Red Tek 12a sounds interesting. I'd like to hear how it performs for you. If your hoses look ok on the outside, i.e. not bulging, and where it attaches to the ferules look good without separating, the hoses are most likely fine and not leaking. But the only way to be 100% certain is to pressure test each hose by itself. I would suggest replacing all the o-rings since they are old and shrunken/ deformed/ not sealing well. If you are not replacing the R4 with a new and reusing the old, I'd suggest resealing it also since it has o-rings also and a shaft seal which should be replaced with a lower leak rate double lip seal.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Red Tek 12a does not have R134a in the mix.

When R134a first came out, the recommendation was to replace R12 hose with barrier hose. Later that was recanted. R12 hose was found to be fine for R134a because it was saturated with mineral oil.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Even though that is not my quote (I just found the info on a site about Freeze 12), I believe it to be true. All shops (at least the reputable ones) will work with R12 and 134a only, and only have and are certified to use equipment for same. They are supposed to analyze the refrigerant before recovering it so their equipment and refrigerant supply does not contaminate other vehicles from the blended refrigerant. The tech at the shop I use calls it "refrigerant harpies" (refrigerant that has been contaminated with a "blend"). I for one am glad the shop I use will not allow their refrigerant supply to get contaminated, as I use them often. I know that I am getting pure refrigerant, and not a blend of anything else. I would have to agree that Redtek and other HC refrigerants can be vented legally and ethically. However, blends such as Freeze12 and the like should not.
Also, I have read that alternative refrigerants (including HC) are for replacement only, and NOT to be used for "topping off".

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All Diesel Fleet
1985 R107 300SLD TURBODIESEL
2005 E320 CDI (daily)

LOTS of parts for sale!


EGR block kit
http://www.peachparts.com/shopforum/diesel-discussion/355250-sale-egr-delete-block-off-plate-kit.html

1985 CA emissions 617 owners- You Need This!
Sanden style A/C Compressor Mounting Kit for your 616/ 617 For Sale + Install Inst.

Sanden Instalation Guide (post 11):
http://www.peachparts.com/shopforum/diesel-discussion/367883-sanden-retrofit-installation-guide.html

Back to OP's original question. I heard back from Codan. Here's their reply. Sounds like he is not certain about his answer, but it's a start. I've asked him to verify his info. NBR is Nitrile Buna Rubber, aka Nitrile or Nitrile Buna

"Info
4:15 AM (5 hours ago)
Reply
to me
Hi

Hose is not produced for many many years.

Could be an NBR inside.

Hans Andersen
Codan Rubber Danmark A/S
Mobile device
www.codan.com"

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Cool. It should be good as far as compatible then... I wonder why the o-rings were butyl then?

If he is right, then all the OP would need to do is change the o-rings.

As old as the unit is, and as poorly made as the R4 compressor is, I'd recommend he flush well with a non water based line flush. Or replace the hoses, and only flush the coils.

I have has three R4 compressors fail on me... Black Death sucks to clean out!

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Where did you get the info that the o-rings were Butyl?

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Thanks for that info funola, I also just spoke with a rep from RedTek and they said they are almost sure our cars dont use the incompatible butyl hoses. They said those are cheap hoses normally found on buses. R12 orings are also compatible with r12a so there is no need to change them unless you want to be proactive (not a bad idea on an old system). I managed to score some cans of real r12 so I am going to charge the system with that instead, but at this point I think 12a would be feasible for our cars and I would use it if i didnt have r12, you will just need to diy because I dont think a shop will hook up their equipment to 12a. And I wont be using the crappy delco r4, instead I have installed the klima sanden conversion kit. The install was pretty straight forward for a conversion and the parts were good quality.

Sounds like the original hose rubber was "nitrile", also known as "Buna-N", which is the material of common black O-rings (flame me if incorrect). As you know, when converting from R-12 to R134A, you should change black O-rings to HBNR (push to standardize on green, but some are blue or red). Viton may be better, but is more expensive and fewer sizes available. Besides refrigerant, compatibility with the oil matters.

All rubber hoses leak, it is just a question of how fast. Barrier hoses are better for all refrigerants. You don't need a Master-Cool crimper, as many other hose clamps will work. Retrofit AC (dealer, Western Auto, Sear, ...) was very common thru the 1970's and most used screw hose clamps (w/ locating finger), and didn't leak. You can buy on ebay, but smooth Breeze screws clamps are probably better. Oeticker stepless ear clamps are even slicker and can be crimped w/ common "nail puller" pliers. If you buy a used Master-Cool on ebay for $150 like I did, you might sell it for the same or more and thus just pay for shipping. Wheeler Dealers used one on this year's 60's Volvo episode. Buy "reduced barrier" hose for a smaller OD. The -10 dies worked fine for me on -12 reduced (suction hose in W123).

__________________
1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans

What were the maintenance history of those three R4's? Are you the original owner? What were the causes of the black death?

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Aren't Freeze12, Red Tec 12a, Enviro-safe, and Duracool all similar HC mixtures? I have used the later since ~1997 in my 65 Newport and now in all my vehicles, incl the minivans after compressor replacements. Duracool is from Canada, and I think more common there. I wouldn't retrofit R-134A today since outlawed for years in many countries and soon to be in the U.S., so you would soon be relying on recovery stock, and perhaps prices rising like it did for Freon. New cars use R1234yc or CO2. The former has safety concerns (read M-B export to France issue) and the later requires extreme pressures, which could lead to expensive repairs in the future. But, the EPA long ago dissed HC refrigerants for somewhat absurd reasons, which you can read on their website. They even outlaw venting HC refrigerant, though cows do that all day long.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans

RedTek and duracool are both basically the same, highly refined butane and propane, freeze12 is a mixture of r134 and something else, not sure but not an HC refrigerant. Im more comfortable putting r12a in an r12 system than freeze12. Im not sure about envirosafe, but I think its HC. Best thing though it to just use r12, I found a bunch on craigslist and that is what I will be putting back into the car.

How's it going with the Klima Sanden R12 conversion? I didn't want to go that route, too much expense, too much work and too much risk. I don't know why R4's have such a bad reputation. Mine is working well after resealing. We'll see how long it stays working well. (Vstech and Jay Bob must be hoping it'll crap out soon). At lease R4's on W123 do not have mounting bracket welds cracking. Does that afflict Klima kits also?

R12 vent temp 85 300D 38.5F @ 87F ambient

Vacuum flush AC system

Re-sealing R4 compressor

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked