Installing a CompressorWorks R4 into a W123
 

Keywords: compressorworks compressor works R4 air conditioning rear seal W123 1983 300CD 300D 300TD Delco Harrison GM
I’m re-habbing my air conditioning and replacing the compressor. This should be an easy job: one belt, six bolts, available parts. But no……
Warning/disclaimer: Venting or discharging your refrigerant (R12 or R-134a) into the atmosphere is illegal (and messy, and dangerous). Get your system evacuated, then work on it.
Wear goggles – there’s no end of greasy crud under your car.
Try to wear gloves – I did sometimes, but the darn Texas summer heat made that more miserable than greasy dirty hands
I’m removing a Harrison HR100T compressor and replacing it with a CompressorWorks 620230 unit. Both are R4, neither are M-B OEM.
I’ll skip the diagnostics that led me to decide to replace it. (highlights: leak from rear seal, probably bad clutch bearing, possible bad front shaft seal and maybe bearing, already evac’d system once…)
Get your parts:

Compressor – bought from a major chain for less than $200. CompressorWorks R4 compressors are made in Dallas and are reputed to be the source for re-branded units for Delco and others. That’s rumor I read on the Internet, but if you’re price shopping, you may want to ask the source before paying extra . http://www.compressorworks.com/

Belts – I went ahead and got all four: 2 x alternator belts, P/S belt, compressor belt. You don’t HAVE to replace the belt, but mine were old from the PO, had some wear and cracks and I figured I’m halfway there with the P/S pump and A/C belt out, so I’ll do ‘em all. It’s probably a good idea to buy alternator belts in pairs, from the same production run. That way they’re no-kidding the same size.

Oil – This is not a trivial decision. Are you going R12, R-134a, or just not sure? If R12, get mineral oil, if 134a, go for a 150 viscosity double end capped PAG, if you’re not sure go with Ester. I’m going 134a, so I used DEC PAG. What is “double end capped”? I don’t know, since I’m not a petro-chemical engineer but it refers to the oil molecule and it is resistant to absorbing moisture. See here for a science experiment with test tubes, graduated cylinders, and words like “polymerize”: http://www.autoacforum.com/messageview.cfm?catid=20&threadid=17571

Seals – this was the bane of the install. More later, but look here to see the rainbow of variety of sealing washers for GM compressors. For this specific install I needed the yellow one and the green one. Of course, I didn’t have them or know that. The major chain compressor did not come with them. The pic for the compressor at the AllParts site shows them, too. Do not assume you can re-use your old ones. http://autoacrepairs.com/sealing_washers.htm

Receiver/dryer – I won’t cover it in this install, but if you’re opening up the system you may as well replace this. They’re listed for some astronomical price, but you can buy Behr brand for less than $20 online.

Get your tools, at a minimum:

Phillips screw driver, 19 mm socket and wrench, 15 mm, 13 mm,10 mm, various adapters and extensions and drives. One of the most useful combos I found was using 1/4 inch drive hinged ratchet with a 3/8 adapter and the 19 mm socket. It made for faster turning after the bolts were loose. I also got the loaner clutch wrench from AutoZone.

1) Wash and degrease as much as you can. You’ve probably got leaking oil line residue, leaking P/S pump residue, maybe leaking compressor oil residue and road grit. It’s messy under there.
2) Get the system evacuated.
3) Loosen the P/S pump. There’s no mystery here, but here are some pics. I removed mine since I also discovered it was leaking from the rear O-rings (and yes, I’ve got a kick-butt DIY on rebuilding those…)
4) My nuts/bolts were all 13 mm. Watch out when loosening the lower inboard because there’s another 13mm bolt back there maybe an inch higher or lower. You may think you’ve got it, but you loosened something else.
5) The upper inboard is the pivot, lower inboard and lower outboard are sliders (note the lower inboard has the least travel) and the upper outboard is the adjuster. This “nut” that mates into the P/S pump body is just plastic, so you may want to think about that the next time you’re torquing down on that guy.
6) Loosen the P/S pump and remove the belt.

7) Unplug the compressor. Take a look at your connections. I think the PO did not have the connection on tight which may have led to an intermittent connection and a slipping clutch. The connectors should be a “spring fit”. The auto-focus wasn’t so great, but one fitting was shiny/worn on the front and the other on the back. The plastic housing was also worn through, so I think the electrical connection was made between the spade fitting and the plastic, not by the actual spade fitting. These were also saturated with old oil, so I cleaned them to get a good electrical connection later. If you remove the Philips screw near the oil lines you have more room.
8)Start loosening and removing bolts on the compressor. I found that moving the compressor was easier after I disconnected the manifold. You did evacuate the system, right? If not, you’re in trouble now. There’s a 13 mm nut/bolt that hold the manifold to the compressor via a bracket and a 15 mm between the two ports. Before you remove that, take a look at the small gap (<1 mm or so) between the manifold plate and the compressor body. That’s what you’re looking for at the end of the job (note: I have no experience with O-ring style R4 compressors, you probably don’t want a gap there if you have an O-ring.)
9) As you loosen the manifold, bright green oil (if it’s a 134a system with UV dye) will leak out. You may want to capture the oil to measure how much is coming out. Since I was going to flush my whole system, I didn’t bother measuring, but I did have a catchment pan. Wear goggles.
10) The 15 mm is sort of a hassle. I couldn’t fit a socket in there and I don’t think there’s room for a ratcheting box wrench. Tough it out.
11) A sealing washer MAY fall out as you really loosen the manifold.
12) There are three 19 mm bolts that go from rear-to-front and one 10 mm adjuster bolt. The pattern is similar to the P/S pump: counter-clockwise from top – pivot, slider, slider, adjuster. I needed to use a variety of sockets and extensions. A hinged 19 mm box end would have been primo. I don’t have one.
13) When the bolts are loose, you can remove the belts. If you’re going to do the alternator belts, now’s the time. I’m not covering that this DIY, but don’t dork up your adjusting bolt – it’s a $70 part. Loosen ALL the nuts and bolts, then turn that adjuster. Put on the new belts and get back to the compressor.
14) As you remove the mounting bolts, the spacers will fall out and roll away or hit you in the face. Wear goggles.
15) Remove the old compressor.

16) The pic is from floor up with the spacers back in place. I’ve got a crappy auto-focus, but on the left you see the middle-sized spacer and the adjuster banjo bolt that goes up to the 10 mm nut on the top. Slightly to the right and a bit lower in the pic is the pivot bolt. Top center in the pic is the manifold, with a sealing washer still stuck to it. Just to the right of that, and behind it in depth of field, you see the long bolt and tube with a thick washer. That bolt goes through the mounting bracket to the thick spacer. This is more/less your pre-assembly set up.
17) Before you put your new compressor in, you should do a few things. You should inspect your lines for any signs of “black death.” Do a search on Google and see what I mean. If you’ve got “black death” then you need to flush the heck out of your system or you’ll be doing this job again soon.
18) If no black death or other crud, then carry on and break the seals on that shiny new compressor. Here is where I screwed up and it cost me time and effort. Dry fit your sealing washers before you do anything else. I ass-umed R4 compressors were all the same. I knew I had a leaking sealing washer, so I bought two new ones just like my old ones. The compressor didn’t come with any others.

19) The Harrison HR100T has two recesses of equal size and equal depth milled into the back – this fooled me into thinking I was prepared. The CompressorWorks has one large shallow recess and one smaller deeper one. Look here for the variety. http://autoacrepairs.com/sealing_washers.htm You may find different AC and parts supply sources that say you need two black ones for your M-B. They may be right for a different model compressor, but not if you’re using the same model CompressorWorks I did.
20) What you’re looking for is the washers to stick up just above the surface of the compressor body. On my old Harrison, the recesses were about 2 mm and the washers are about 3. On the CompressorWorks, the deep one is a little over 4 and the shallow a little over 2. The 15 mm bolt on the manifold will sandwich the rubber sealing faces against the compressor body for a tight fit. If the manifold fits against the body of the compressor, or it’s uneven, then it’ll leak. (Note: this is not an O-ring install).
21) Dry fit all your bolts: the short 15 mm for the manifold and the long ones to bolt up the compressor. First, it’ll be peace of mind that when you’re installing the compressor and the bolts aren’t moving and you’re sure you’re cross-threading a metric thread into an SAE hole that you aren’t actually doing that and they DO fit. Next you’ll see how much dirt and crud are in the threads and how gritty it is and you’ll be inspired to get the old toothbrush out and clean them. You’ll think you’re really clever when the bolts go in easier later.
22) Once you’re sure you’ve got the right parts, you can put oil in the compressor. You MUST do this. I’ve read some compressors come pre-oiled. Mine didn’t, and it’s just as well since I wanted the DEC PAG oil in there. The exact capacity is not entirely clear. The FSM section 83-520 has specific quantities to add depending on what you’re doing and how much oil you’ve removed. The compressor re-install section, 83-522, says a total capacity of 170 cc, or about 6 ounces. Your call. Too little oil is bad, too much is very bad.
23) CompressorWork’s installation instructions http://www.compressorworks.com/InstructionSheets/Install%20Instr%20-%20AC%20Compressors.pdf say to add 2-3 oz to the suction side. This is consistent with pretty much everything else I’ve read. Then they say to turn the compressor at least 10 times. Now you need the loaner clutch wrench from AutoZone.

24) The clutch wrench has three adjustable pins that mate up to holes in the clutch. I adjusted them when it was clutch-up, then turned the whole thing upside down.
25) I put one-third-ish of the 8 oz bottle into the suction port while holding the wrench stable and rotating the compressor body.
26) Some of this oil will run out when you try to mount the compressor. To minimize this, I loosely replaced the rubber seal in the ports.
27) You can lube and place the green sealing washer over the manifold now.
28) Reinstalling is somewhat of a hassle, since you’re trying to align three holes with spacers on two of them, the oil is starting to drip, the compressor is heavy and awkward for one hand while you’re trying to get the other hand with wrench in place.
29) The technique that worked for me was to start with the adjuster screw bolt. It seemed to line up easiest. At this point you may want to consider putting the belt on since you’ll have the most freedom of motion. I had fitment issues, see below. The downside of doing the belt now is that you’ll have no guarantee you can get it off without the manifold attached, just in case you have the wrong belt or something.
30) I used the manifold bolt to pull the manifold closer, removed the rubber seal, put a jar to catch the dripping oil, placed the yellow sealing washer in place and struggled getting the 15 mm bolt in place. The hoses are stiff, but I found that if you push up on the manifold the hole line up and you get the bolt to screw in. Pushing up on the manifold was the only thing that worked for me. For a while I was sure the bolt didn’t fit and I was stripping the hole, so I removed everything to check. It fit fine. I didn’t feel clever. End torque on this bolt is 50 Nm, I think. I can’t get a socket in there, so my calibrated 15 mm Craftsman box end has to do.

31) I put the other bolts in place. I didn’t have too much trouble getting them aligned and in. I left them very loose.
32) I was puzzled when I could not get enough slack to put the belt on. I could see I had plenty of travel left, but the compressor wouldn’t move. I discovered the manifold nut was now hung up on the lower oil cooler line. Since the manifold is connected to the compressor, it has to move, you can’t just loosen the small connecting bolt to the mounting bolt.

33) I loosened the oil cooler line brackets (10 mm sockets) and forced the nut past the cooler line in order to get enough slack to get the belt over both pulleys. Then I had to force the nut back up past the oil line in order to tighten the belt. My oil cooler line is ContiTech, but I don’t think it fits as well as the M-B stamped one I took off. I really need those 2-3 mm back.
34) When I used the tightening bolt, I did get some clearance that the nut and hardline are no longer touching, but I’m not happy with the risk to the oil line and may replace it. I am concerned about maybe having to overtighten the belt and put wear on the compressor and clutch bearings to keep the lines apart. I’ll watch it and see how it plays out.
35) In a previous junkyard expedition, I pulled off an intact plastic clip to replace my worn through one for the electrical connection. To ensure I got a tight fit on the spade connectors, I pulled the connectors all the way through the cover, then put them on individually onto each connector on the clutch, then I pushed the plastic cover into place. Don’t forget about the Phillips screw if you removed that to get cable slack.

36) I tightened the belt, then tightened the three mounting bolts. FSM says 60 Nm for mounting bolts.
37) In the pic, you can barely see the slight gap between manifold and compressor body and a snug clean electrical connection. You can also see what I didn’t notice until very late in the repair. My manifold was repaired and rebrazed at the hose fitting. There’s a large blob of brazing material right in front of the hose. I don’t know if he hit a rock or had some other damage, but I’ve never seen it leak there, so I guess it’s tight.

38) Install a new P/S belt, if desired. Remember about the plastic tension bolt and tighten up the other three mounting bolts. FSM says 25 Nm for 8.8 hardness and 35 for 10.9.
39) Double and triple check for misplaced tools. Do a “tool count” and put them away. Take a break, come back out and look everything over one more time.
40) Dry run your belts and other connections. Make sure the A/C is turned off so the clutch doesn’t try to engage, even though the low pressure switch should stop it.
41) Have your system vacuumed and charged (note: you should also replace the receiver dryer, but this DIY is long enough already).
42) Before you go all wild with your new in-car coolness, you should burnish your shiny new clutch. This is what Ryder says about burnishing: “Burnishing is the cycling of the clutch to allow a wearing in of the engagement surface area. The reason for burnishing a clutch is to increase the initial starting torque. Most technicians fail to follow this important procedure when replacing a compressor or clutch. An unburnished clutch can produce a low torque condition, causing the clutch to slip and thereby fail. When replacing a clutch or compressor & clutch assembly, follow this important burnishing procedure. Run the engine at 1,500 to 2,500 RPM. Using the controls on the dash, cycle the clutch ON and OFF at a rate of 10 to 15 times per minute for a total of 50 cycles minimum. This should bring the clutch up to operating torque capacity.” The Ryder page is an excellent reference with clear simple paragraphs: http://www.ryderfleetproducts.com/cgi-bin/ryderfp/technicalbulletins/acClutchfail.jsp
43) I haven’t used my system yet since I’m still waiting for a new parallel flow condenser (Yeah, thanks a lot for expediting the already two week overdue parts Arizona Mobile Air – I hope your parts are good, because your service is lacking…UPS ground on Wed and you think it’ll be here by Friday?) Assuming they ever get here, I hope to have the system evacuated, leak checked and charged soon.

Yak, Did you get the PF condenser yet?

No. I was on vacation. I talked to the guy who built the new hoses and he insists it was shipped but they couldn't track it. They were ready to build a new set of hoses and overnight it. Since I was gone, I said I'll wait. It didn't come in while I was gone, so now they're shipping again. It'll be here before the end of the week, I hope.

Rr compressor
 

I just purchased a NEW Compressorworks R4 and was wondering how your system turned out? Thanks for your response

I've installed dozens of them. ALWAYS a happy customer with it!

if you've got any questions, just start your own thread, and I'll likely see it, and chime in with help for ya!

BIG thanks...will do

I paid $169.99..free shipping from a top rated ebay seller. It looks super and came with the sealing washers. Is that a good price? Thanks

if it's a real CW compressor, and it came with the red and green washers, then yes, it's a great price.

If it is a copy from ***** it's an excellent job. I got it from *******************
Packaging was far above other r-4 units I have purchased. Likewise for the documentation on the box and inside.
Sealing washer package #150054 contained Yellow, Red, Green washer and the long and short Inserts. Also assembly insttructions.
CW part # 620230.
Not sure yet as to when I will install it.
Hope this helps.

Please do not list competing parts suppliers on the forum! thanks!

you can toss all the parts but the red and green washers. the yellow one is for a different car, as are the two inserts.

BIG thank you...my car is 116, 1980 300SD ...YAK used the yellow and green on his 123...is that because the manifolds are different? The CW compressors 620230 are the same.

I need to do the same. Wifey is driving the 83 300D after we sold the E420 which had ice cold A/C. Maybe we should just continue on this thread with the repair process to keep it all in one place for future DIY?

Ok by me if our moderator approves...

The manifolds may be different. The driving factor is the interface between the manifold and the compressor.

Your compressor has the same model number as the one I installed. The milled-out holes on the back of the compressor have different depths and different diameters.

The W123 manifold in my car (and I assume most W123's) had a flat surface with a short section of tubing. The yellow plus the larger diameter hole and shallow depth, plus the green and the smaller hole and deeper depth combined for a flat surface a mm or so above the surface of the compressor.

When you tighten this combination of parts down, then you're compressing the rubber in the washers for a tight seal.

I assume it would also be possible to get close by using the red and the green, and this would create a bit more stand-off from the compressor.

Not all R4's are the same. Older ones used O-rings instead of sealing washers, as described above, my Harrison used two same-size black ones.

I would suggest that if you don't use the yellow one, then you 'might' need the little section of tubing in the kit to keep the sealing washer centered in the port since the milled out diameter of the larger hole is a few mm larger than the red or green. Maybe vstech will chime in there.

I'd definitely dry-fit before committing to the install with oil in the compressor and being upside down on your back. It sucks to be in that position trying to figure out why things don't fit together...

From the link in post 5:

Green: 5.5 mm, 29.9 mm
Red: 3.8 mm, 29.9 mm
Yellow: 3.0 mm, 33.2 mm

Good pics from a JimmyL thread here: http://www.peachparts.com/shopforum/diesel-discussion/155369-ac-manifold-vs-compressor-vs-seals-vs-my-brain-pan.html

I am NEARLY certain, I used the red, and the green...

now, I gotta go dig out the spare parts, bin and verify what was left...

It seems to me that every time I have done one, I have used the red and green (123's).

Thanks YAK--Tray Carlisle recommends the Yellow and Green for the 1980 300SD. Appreciate your input.

I have red spacers left in my bin, so that means the YELLOW and GREEN were used.
sorry my brain fart left bad info!

Autozone has an excellent DVD on A/C repair for $8. It's great for newbies like myself and makes me comfortable with tackling this job. I have my indy giving me a price of a compressor replacement fix. If it's prohibitive, I am going to go this route with enviro-safe refrigerant. What concerns me about r134 repairs is that they don't seem to last after all the money spent. The PO of my 83 300D had her indy retrofit r12 to r134 and it only lasted 2-3 years before the compressor went out. Now that my wife is the primary driver, I have to get the A/C repaired. Many years ago I had a 84 300D that my indy retrofitted and it only lasted 2-3 years before the compressor went out. WTF, is this typical??

Thanks for the heads up, buch32, I just ordered a compressor, dryer and expansion valve from them. They've got the compressor price at $155. Although I've done brakes & rotors, ATF filter changes, I've never done A/C work but indy pricing is prohibitive and longevity is questionable in retrofited r134 system so I've got to learn. I'm gonna need help on this, thanks guys.

I believe, and I'm sure the other ac experts (vstech, air&road and others) agree:

The 123 was designed for R12. Putting other than R12 in results in the following:
- sub par cooling (I don't understand the exact physics but 134 can not move the heat as well as 12), and this leads to
- damaged components (high side pressure spikes in hot weather beyond design limits) I have read several stories of people suddenly venting their refrigerant in traffic when a hose or pressure switch or compressor seal lets go.

Besides being against the law and the green police, vented refrigerant is not good to breathe and I remember one guy getting the refrigerant and oil sucked in to the intake causing a temporary runaway condition.

Just my 2c worth, I'm a believer in R12 after vstech fixed my ac the right way.

I feel blessed to have my 134a converted 1982 300CD working great for at least 2 summers (the present one and the last) with very low vent temps (low 40's). I even have to turn the fan to low sometimes when I get too cold. It has been well over 100 degrees here in the desert of So. Cal. the past couple months. I think the trick is to have a completely clean system, and add the proper amount of refrigerant. On the coupe, I started with a good USED R4, and completely flushed the entire system with the good solvent. Checking for leaks is also critical. My A/C guy (has recycling/recharging equipment) has done many 'Benzs for me, and is getting good at them. I do all the mechanic work, and he just checks for leaks and recharges the systems for me (about $80 each car). I don't know why other folks are having so many problems with 134 conversions in their 123's, but mine seem to be working just fine. I need to use 134, as R12 is not very available here in CA (also very pricey!). So far, I have had great success. Wish my luck on my next job: 1984 300SD....Rich

wow, it's good to hear from someone that's had 134 successfully converted into a pre 84 123chassis!
keep in mind the cd has a smaller volume to cool, smaller windows, and fewer doors... likely you have the windows tinted and I bet the car is a light color. also, in the desert, you are not dealing with humidity... that's a HUGE heat load on a cooling system!
88F with 60% humidity is about 3 times the amount of heat as 100F in 10% humidity... that's a lot when often in TX or SC etc, it's 95+ with 90% humidity!!!
these cars all pull in air from outside! so it's OUTSIDE humidity that is being dealt with! even with the max cool setting, there is a large % of outside air flowing through the car...

WOW you are good! You must have cheated (looked at my signature). Yes the car is white, but no tinted windows. I do keep a windshield shade in place when the car is parked, and that helps the car cool quicker. I am basically a cheapskate, and don't want to pay for r12 if I don't have to. The 134a works so good, I see no reason to change. I am hoping the 126 will turn out as good. It HAS tinted windows, but is gray in color.

the 126 has fine cooling, I got good results with 134 in my 82 with stock condenser.
keep in mind the MASSIVE cleaning job I perform each year though.
an 84+ condenser will help cool the car even better.

Is the Compressorworks brand a remanufactured unit or new? I know I need to replace the compressor, but not sure which is the best one. I know I need to stay away from the Chinese copies, but what about Delphi? Chances are slim that I find a good used one like I did for my coupe. I have tried one from Kragen (now O'reileys), and it was junk right out of the box.

The one for the 123 is, as far as I can tell, a brand new build. I got mine from a chain auto parts store and they did not ask for a core.

I believe they purchased the design from Delco/Harrison and are building these in Dallas.

I decided to go with the Compressorworks unit from the 'Zone. $207 out the door. I got ready to install it, and read the instructions about adding oil and turning it 10 times. I assumed it would turn by hand. When I tried to turn it, it would not move at all. I finally got it to turn a little, but it made a scraping sound like a broken ring scoring a cylinder wall. I assumed it was bad, so I returned it, and got my money back. The next day I talked to my buddy at my local A/C shop, and he said "you can't turn a new R4 by hand, you need a special wrench". He said that is normal for the R4, and that there was nothing wrong with the new Compressorworks unit. I wish the instruction sticker on the back of the compressor would have said that the compressor will be very tight, and that that was normal (I would be driving with A/C by now!). I can't bring myself to go back to the Zone and get the R4 again. I decided I am now going to try to make a bracket to install a Sanden. I have had enough with this GM garbage!

nahh. you can turn a new CW R4 by hand, but you have to be VERY stingy with the oil in it.
if you put too much oil (more than an oz) and the oil will bind the pistons.
I like to dribble a small amount of oil in, then turn it a few times, then dribble some more in, and turn it another few times. then let it spill out. and spin it some more.
I've NEVER had a CW compressor give me problems turning by hand. (I'm pretty strong though...:D )

If that's the case, then I got a bad one "right out of the box". I totally understand the procedure, but this one was clearly bad right from the start (IMO). Either way, I am in the middle of fabricating a bracket for a Sanden. I have a core and a spare engine in my garage, so I can do a mock-up without crawling under the car. I just got back from P-A-P with a bracket and a good Sanden. I will start another thread with photos and specs. I found a good bracket and compressor on an '86 Mitsubishi pickup (Dodge Ram)....Rich

That's cool that you have an extra engine for mock-up :cool:

It was a MOFO figuring mine out with the engine in the car...

Sounds like all great minds think alike, I just got back from the JY where I too got a Sanden and a bracket. :)

Mine was off a RX7 and appeared to be an aftermarket one with the "generic" bracket like the York adapter ones. It was already removed, so I couldn't see how it was mounted. I'm going to try to see if I can fab something up that will let me shoehorn it in, but I'm kind of doubtful. The subframe supports on the inner fender well on the R107, plus the UCA brackets make it very, very tight. I had to eliminate the R4 completely because there was no possible way it would fit. I think my only hope now is to somehow mount it solid, tight to the engine and then figure out how I can use a tensioner for the belt - probably something like what the one on the original 380SL used.

The compressor was only $20 so I think it's worth playing with a bit. Unfortunately I don't have an extra engine, so I'm going to have to pull mine out sometime to do the experiment.

I'll watch for your thread.

I think someone suggested moving the PS pump down and placing the AC compressor in it's place. This would be workable on a 116, not sure about others...

I have not seen the Klima kit installed, so I am at a disadvantage. Is the bracket you got aluminum or steel? If steel, it would be much easier to fab something. Unfortunately, the one I got is aluminum. As far as mounting, it is much easier to mount it solid and use an adjustable idler.
I will start another thread, and let this one continue....Rich

I, for one, would be interested in learning more about this strategy. Any pictures around on how this was done?

So we don't hijack this thread anymore (sorry), here is the new thread:
http://www.peachparts.com/shopforum/diesel-discussion/320985-installing-sanden-compressor-617-looking-all-options.html#post2967763

My indy use the red on the low side and yellow on the high side. Although it held vacuum, it leaked out a week later when pressured on the yellow, high side. So today he use the green on the low and the red on the high side (thinking red= high pressure). His boss wanted to charge me a half hour labor but I refused as it leaked out. As it is, I have to get 2 more cans of ES-12a.