AC charging

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Brandon_l1000

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To be honest with you, I bet you can sell that R12 on CL for $25 a can. Sell 4 cans for $100, then take your truck to service place and usually an AC check up is $59.95-$79.95 and includes 1lb of freon, probably more for R-12 but see if they'll use one of your cans and keep the price the same. :shrug:

Yeap r12 is expensive
 

HotRodPC

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I'm starting to figure out, it's actually cheaper in the long run to go ahead and just convert to R134a and be done with R12. The trick is going to be to make sure you get a good vacuum pulled on your system to get all the R12, moisture and contaminnnts out of your system.
 

oneluckypops

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I'm starting to figure out, it's actually cheaper in the long run to go ahead and just convert to R134a and be done with R12. The trick is going to be to make sure you get a good vacuum pulled on your system to get all the R12, moisture and contaminnnts out of your system.

its no trick at all. if you do it "properly" you should actually flush the entire system with an a/c flush solvent, THEN vaccume the system prior to re charging
 

HotRodPC

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its no trick at all. if you do it "properly" you should actually flush the entire system with an a/c flush solvent, THEN vaccume the system prior to re charging

Leave it to you to **** up my plan. :rofl: OK, so I'll punt on that truck for now and concentrate on the K1500 since it has the belt and all hooked up too and it's got a sticker that says it's been converted to R134a already, and has the R134a adapters on the high and the low sides. The fan blower is bad though and it don't blow. I do have a bright light on high, with a continuity tester, and it gets dimmer as I turn the fan swtich down to low, so I have power, it's the blower motor, and no run hooked direct to the battery either. The compressor does not come on either. Is it safe to assume the freon level is low enough the switch on the accumulator is not allwoing the compressor to get power? Do you know if the compressor can detect if the blower is hooked up and a complete cirtuit or not? I was going to add a can, with a guage of Oil, Sealant and Freon and see what happens. When I bought the truck, the guy said the AC was working fine the last summer, and I bought it in November, but now it don't work.
 

HotRodPC

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Soooo Pops, How about a write up thread on R12 to R134a conversion? Some pics of the process too would be cool. You know an outline of steps etc. Even if you don't have a cam and don't have a project to do it on currently, even though a SB would be best, we can find some pics off the internet and I can edit them into the thread. Tis the season brah !!! With what little I've played with auto AC in my younger days, and what I've found on the internet, I feel confident about doing my own now, but not good enough with the explanations as of yet to do a write up.

BTW, I think I've got a fridge compressor I saved for making a vacuum pump for this purpose. Not sure it'll last though. I found an article on how to do this, homemade vac pump, and some compressors are good for it, some aren't. Usually the round ball type will work, but the tall cylinder type will usually just run til they quit and usually in the first vacuum job.

For now I was going to use this Air Vac tool with an air compressor to vac my systems.
 

oneluckypops

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lol I dont see why your plans would be ****** up now. A can of flushing solvent usually only runs about 20 bucks.


Oh and on your other truck, more then likely it would be safe to say that its low. BUT I would reccomend turning the A/C on and testing the light green wire at the cylcing switch on the receiver dryer. If it has power with the switch on and the dark green wire does NOT have power then it is EITHER low on freon or a faulty switch.

Blower motor operation has NO impact on the compresser clutch energizing.

Oh and as for a write up for R134a conversion. I will respetfully decline. You know how I Feel about people servicing there own A/C systems with out the proper training. NOW with that said I will GLADLY teach anyone that I feel has the ability but lacks the experience. To put the information out for any tom, dick, and harry to read on a public forum is IMO neglagent on my part. A/C systems can be very dangerouse and NOT everyone should attempt this on there own. There is SOOOOOOOOOOO much more to fixing an A/C system then just findind and fixing a leak and recharging.
PM or give me a call and I will walk you thru it step by step.


Edit: Oh and I have heard of the "home made pumps" but have never really researched them all that much. Honestly My vaccume pump works fantastic and is very affordable. I have never used the air vacs but I do know a tech that uses one and he says it works great so long as you turn your psi on the compressor down otherwise it blows by.
 
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HotRodPC

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Cool, Thanks. I'll be checking those wires on the cycling switch. I didn't think the fan mattered, just that mine is bad and I have one on the truck out at my dads. I'm figuring out though, if I get the AC working, a new motor is $20 at O'Reily's. A trip to dad's cost $45-$50 in fuel plus time, soooo the new motor is likely going to win out IF i get that compressor clutch to engage and see the lines sweating. On the C20, I'm thinking I will just take it somewhere, get it cleaned with solvent, vacuumed down and converted to R134a. Then after that, I think I can handle maintaining it in the future. When that truck gets the Olds 455 in it, it'll be getting a compressor move to the other side of the motor and an A6 compressor. Right now, it has the DR6 or HR6 type.

I kinda thought the same thing on the write up, but I figured done right, the reader might just realize how complicated it can be and decide to punt and take it to a pro, instead of thinking he can do it. Some people are honest with themselves, but many are not too, so you're probably right in not doing it.
 
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oneluckypops

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Cool, Thanks. I'll be checking those wires on the cycling switch. I didn't think the fan mattered, just that mine is bad and I have one on the truck out at my dads. I'm figuring out though, if I get the AC working, a new motor is $20 at O'Reily's. A trip to dad's cost $45-$50 in fuel plus time, soooo the new motor is likely going to win out IF i get that compressor clutch to engage and see the lines sweating. On the C20, I'm thinking I will just take it somewhere, get it cleaned with solvent, vacuumed down and converted to R134a. Then after that, I think I can handle maintaining it in the future. When that truck gets the Olds 455 in it, it'll be getting a compressor move to the other side of the motor and an A6 compressor. Right now, it has the DR6 or HR6 type.

I kinda thought the same thing on the write up, but I figured done right, the reader might just realize how complicated it can be and decide to punt and take it to a pro, instead of thinking he can do it. Some people are honest with themselves, but many are not too, so you're probably right in not doing it.

Hotrod
I have an extra set of manifold gauges that are not used anymore, I would make you a hell of a deal on them if your interested.

They are about 2 years old, BUT they will need atleast a new service hose (yellow). If you want to check to see how much hoses are Ide sell them or trade them to you. I bought a different set just because I needed them when I didnt have my others when they were being stored cause i didnt feel like spending the money and time to go get them.
 

HotRodPC

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I might. That guy on that set of next to new only used 2x Matco set will take $75. It's a $249 set apparently. Had 2 sets of hoses to avoid cross contamination, and does both R134a and R12. Of course they all do that with just changing the hoses. I'm supposed to meet with him tomorrow afternoon.
 

BlazerguyinAZ

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Too bad they couldn't just answer your question. Went through allot of replays before somebody would help. Anyway, I'm going to do the same as you to see if there is a leak in my system (using dye) or if the pressure release valve just opened up because of excessive heat and not enough circulation. (idling in 112 deg temps in Arizona)
 

yevgenievich

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Autozone rents gauges and vacuum pump. Napa rents just vacuum pump
 

1low4x4

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i bought the 20 dollar air vacuum from harbor freight 4 days ago to suck down my brothers AC system on his 86 and it worked great.

Taking my truck to a shop is not an option, ever. Ill learn and buy the right equipment before I let ANYONE around my truck when im not around
 

74propu

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I have been doing a/c work for 40 years from car a/c to 200 ton freezer systems changing from r-12 to a 134a Freon is not as easy as putting on a adapter and charging . to do it right and get the a/c sys to last you must change out the dryer orifice tube all the O-rings drain the oil out of the compressor ( new compressor easiest way) and the new compressor is designed for r-134a then fill with the right amount of 134 pac oil then vac down the sys and see if it holds vac . then you can start charging with the 134a it will not hold the same amount as it did with r-12 . ok so you have to know the out side temp where the truck is sitting while doing this (in the sun / shade) the barometric pressure and humidity to know what your l/p and h/p pressure should be . if you have to ask where the orifice tube is don't try this take it to some one and pay to have it changed over to 134a
long and short by the time you bye all the parts you need to change over it may be cheaper to stay with r-12 and pay the price of it to a pro
this is just my 2 penney's worth
 

1low4x4

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But all that can easily be learned online. Changing all the parts you mentioned is easy. Anyone with half sense and a set of gauges can learn to do AC work just like anything else I the truck. Y'all act like its some forbidden impossible process
 

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Throw a can in see what happens
 

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