R12 System capacity

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tompumped

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I just realized how stupid i sounded. Wow

They wouldve put three pounds
 

rubydist

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1 lb = 16 oz whether by fluid oz or by dry oz. 2.75 lb = 2 lb 12 oz = 44 oz. The little cans are 12 oz, but they are 3/4 lb, not a full pound.

iirc, the capacity of the Gen1 and Gen2 R12 was the same. I didn't remember it being as high as 44 oz, but that's what the sticker says...
 

tompumped

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Well thankfully the 134a discharge hose will work. I changed the o ring on the high side ball valve to hnbr and I took off the pressure switch.

There was a schrader valve under the pressure switch. It just so happens I was able to thread on an r12 high side cap in place of the switch. I had to file the cap down a bit so it didn't hit the step before bottoming out. I thought about changing out the schrader valve but i'm not certain the valves I bought are actually r12 compatible even though they are sold as such. The oem ford piece was brass and seemed much better quality.

I'm disappointed that the test port valve is a ball valve and it can't be replaced without losing refrigerant. Believe it or not they have a way to replace valve cores with a special tool and minimal loss.

It seems like a rig that wont last after rereading, but it will work, the only thing i'm worried about not being compatible is the ball valve. I was hoping it was a normal schrader and I could just put one of my r12 schraders in.

One thing that's worth mentioning the barrier hose is larger on r12 vs 134a. Surprisingly it was the same goodyear galaxy hose that is on the oem r12 liquid line I purchased from the same seller.
 
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rubydist

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The hose comes in two types, a "standard wall" and a "thin wall" such that there are two different od's for the same id hose, depending upon the wall thickness. It is not different for R12 v. R134a, just a matter of whether the hose is provided in the standard or thin wall. The thin wall was developed so that the bend radius was reduced and the hose was more flexible.
 

tompumped

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I didn't know the reason for the standard vs thin. The funny thing is I ran into this working on a piece of equipment last summer, but I never knew the reasoning behind it. I went with standard barrier hose recrimped onto the oem fittings that fed a red dot rooftop unit.

If anyone is in need of just replacing their barrier hose or a crimp failed find a place that works on heavy duty trucks and buses, they will most likely have the capability. You can also buy the ferrules, crimp tool and dies online.
 

rubydist

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Yeah, when I put the V8 in the RX7, I bought the crimping kit - it cost about the same as paying to have the hoses made, but from now on I can make my own for way less than having them made by someone else. Unfortunately, that was when I learned about the two thicknesses of wall on the hose, so I have a few connector pieces left over...
 

zak

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The nice thing with R12 is that if you are a couple ounces low or high it really doesn't effect the performance that much. R12 also offers lower head pressures, something to appreciate when the clutch has to pull the compressor in while cruising on the highway at 3000 rpm. Overcharge a few ounces of R134a and you are likely to pop the overpressure port (BTDT) getting oil all over and potentialy blinding you freeze burning you etc.

Are you sure the compressor was set up (proper oil) for R12? If it had R134a based oil used at assembly and you run R12 that is basically a death kit.

Sometimes to get all the refrigerant in I spray the condensor down with water, but extreme caution should be used when doing this with R134a (see above)

On edit, you did do a vacuum leak up check, and pump on the system for a couple hours before filling?
 

tompumped

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I drained the compressor oil and replaced it with the ford mineral oil stated in my 92 FSM. I took the part number right out of it. I had no unusual noises with the original compressor and never heard a compressor make a noise quite like this. I've owned three 92s with r12 systems and never heard this. I shouldn't continue running it, but i'm waiting on the compressor and two hoses. It's funny that another member purchased from the same seller and his compressor lasted two days before it locked up. I think it's no coincidence, they were also shady and the compressor wasn't a four seasons product as stated.

I did a vacuum test for longer than I should've. I actually let the system sit over night to make sure it held. I have no leaks. The original system had a leaky shaft seal that's why i'm going through all this trouble. Not to mention my discharge lines and suction/accumulator lines are rusted.

For the first time I put the cans in warm water and it was amazing how quick they emptied.
 

tompumped

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Yeah, when I put the V8 in the RX7, I bought the crimping kit - it cost about the same as paying to have the hoses made, but from now on I can make my own for way less than having them made by someone else. Unfortunately, that was when I learned about the two thicknesses of wall on the hose, so I have a few connector pieces left over...
If it was my money I would've bought the kit, I didn't even ask or see the price it cost to make the hose.

That car must be awesome, how difficult was the conversion? I can't wait to do either an s10 or rx7 v8 swap.
 

tompumped

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One thing many people don't know about is the fact that the FSM calls for thread sealant on the bolts holding the manifolds to the compressor. I use a loctite product that's the best thread sealant i've ever used.
 

rubydist

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Well, I didn't mean to take your thread off into the woods... The Ford 5.0 is not a great fit in the RX7 due to the front crossmember - the LSx is a lot better fit but I am hopelessly a Ford guy, so that's what I put in there. GR40P heads, stock cam with 1.7 rr, ported intake, headers. It was the most fun I've had driving in the mountains - very neutral handling and like its on rails. But, we decided to move on, so I sold it and have started a new project (another 5.0 build). It was fairly difficult - custom fabbed motor mounts, trans mount, radiator and condenser. But, I got it all wired up with the Mustang pcm and all the gauges worked and it passed emissions. About as much time in the wiring as in the mechanical stuff...
 

tompumped

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It's all good it doesn't truly matter, I got the picture I was looking for.

At least you admit it's hopeless. I can't deny what I know, the engineering behind it and life experience. If it wasn't for being taught a lot by an old timer who rebuilt high dollar Chevy's I probably wouldn't be so biased. Not to mention there's a very good reason that the dirt track near where I grew up everyone ran small/big block Chevy motors. I'm not a Chevy guy, I look at the truth and facts behind it. I couldn't allow myself to purchase and build an inferior motor when I can have the best small block ever produced. From what i've heard the ls series engines are great also, but I don't truly know.
 

rubydist

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what's interesting about the "new" LSx Chevy V8s is that there is a whole lot they copied from the Cleveland heads. A lot of people say that is the motor Ford should have built instead of the modulars...
 

tompumped

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Interesting, I didn't know that. I'm surprised the car handled so well. I do have respect for the 5.0s i've seen them take a lot of abuse growing up from friends who had them. Not to mention at the same time the chevy 5.0s made pathetic horsepower.

I found a 4 seasons condenset for wholesale closeout pricing and bought it. I wonder if its for r12 and i wonder if the capacity changed with the 134a condenser.

Can someone tell me if these rebuild kits come with shims for the clutch. Im afraid ill have to reshim the clutch.
 

tompumped

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http://m.ebay.com/itm/222558944789

Are those clutch shims?

I should've just replaced the shaft seal and reused my old compressor.

So far all total this is what everything cost:

NOS compressor F1DZ19703A $289.12
4 seasons 54318 Condenser $78.63
2 15oz cans and 2 14oz cans R12 $84.95
NOS oem suction hose YF2022/YF2062 F4DZ19E636A/F3DZ19E636B $136.20
NOS r12 Liquid line (supposedly the orifice tubes are different?) E9DZ19835A $45
NOS r134A discharge line F4DZ19972A $90
UAC HA 1270c R12 Accumulator $34.16
NOS pressure relief valve F1CZ19D644A $15.07
Side can tap, the top mount can taps are junk and a waste of money: Robinair ROB10102 $20
Compressor Clutch hub remover and installer plus spanner wrench $41.58

$834.71

I wish I didn't add it up then I could've tried to tell myself i'm not addicted to buying auto parts online. I had no leaks in the system, but the discharge line and suction lines are rusted bad. I could've just installed a new compressor and been done with it, but now I will have all new components except for the discharge manifold with muffler, clutch assembly, and the evaporator. The discharge manifold is still available but I had to stop myself from buying it. It was another $142. It is part number YF2058, F4DZ19E574A. The clutch is coming off the rebuilt compressor hopefully it lasts.

I'm fairly certain YF2199 F4DZ19E636B would've worked in place of the suction hose I purchased. I originally purchased that and it turned out the seller had the exact one I needed.

I could've bought another SHO for a few hundred dollars more. I honestly didn't know it would cost this much and if I did i'd have probably just slapped in a new compressor and called it a day.
 
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rubydist

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the compressors did not change from R12 to R134a.

I also do better if I don't add it all up...
 

tompumped

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I know the compressors are the same. I guess you meant condenser, it must have been bad information that I read. I read on here that they had to put in a larger condenser to deal with the higher head pressures and higher temperatures associated with 134a. Turned out rockauto didn't have one left so I got the 7014312 APDI/PRO for $75.34


I just purchased mt2039 from autozone for $7.41 shipped. If it saves me a trip to the store for washers to shim the clutch it's worth it. I had no idea you can order parts from autozone and have them shipped to home for free ground shipping. I'm going to be ordering more from them.

I also found out I could've just pried off the clutch plate with a couple screwdrivers and pressed it back on with my press.
 

rubydist

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Sorry, I mis-read your earlier post. I think the condensers are the same, but I'm not sure. Either will work, even if they are different.

When the clutch wears, you remove a shim, not add. However, there are normally two in there, one thin and one thick. It may be that sometimes you should have two thin rather than one thick, so it may make sense to have some extras. I never actually had a clutch wear so bad that I had to take out more than the thin shim.
 

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I didn't know what i'd run into swapping the clutch over to the new compressor. The new compressor doesn't come with a clutch on it. thanks
 

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I would recommend not buying that accumulator it was the worst copy of an a/c line i've ever seen. It had to be bent in more than one place to make it fit. Not to mention the pressure sensor ****** used a smaller o ring. When I dropped the o ring into the pressure sensor it didn't fit nearly as snug as the original size and I couldn't use the original because the id was too large for the fitting. It held vacuum for half an hour so it's got to be fine.

I found this literature in the consenser box. 20170722 2338591

At first I thought it pertained to my application but the part number listed on the top is for 91 and the brackets that came off were identical to the ones that came with the condenser. I'd imagine by 92 they all had this high efficiency condenser.

I reused the clutch assembly off the reman compressor and I should've bought new. The compressor was "rebuilt" but the bearing had to be original it didn't feel new at all and the clutch had noticable wear. Hopefully in the future I can change the clutch by unbolting the compressor and leaving the system charged.

The new compressor came with shims and o rings. The noise is gone
 
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