A/C Compressor went out

[tucsonjwt]

So, I have choices. Reman or new, AC Delco or Four Seasons, old style or new "S6 style", non-switch type or not, 5" or 5.12" diameter pulley.

Has anyone tried the new S6 in place of the A6? They are lighter but I don't know anyone who has used one.

How do I know if I need a non-switch type (I assume this means non-pressure switch type.)

I have had no luck with reman a/c compressors in the past.

Is it true that the old tube and fin condensors should be replaced with a new a/c compressor, or can they be adequately flushed out?

How do I know if I have a 5.12" diameter pulley? I am not sure exactly what the proper measurement location is, and I don't know if I can trust my tape measure to be accurate to 1/8" using my eyeball.

[Big Port Jimmy 6]

I used one to replace an A5 on a 59 Cad and it worked just fine. Jay

[nm78bronco]

A company called Alma Products makes brand new A6 compressors. I recently had a one of their new A6 compressors installed on my 1976 suburban. The AC mechanic said it sounded "smooth", but time will tell if the quality is any good.

The A6 is still used for some new construction equipment type vehicles I believe.

I was interested in the S6 too. I think its made by Nippondenso; my 1999 Toyota Avalon has a Nippondenso compressor I believe, and it has never been serviced to my knowledge and the car has over 400,000 miles on it and the AC is still cold. (I bought the toyota when it had 70,000 miles). If the quality is the same as on my Toyota, then the S6 would have outstanding reliability.

Thanks for your input about the condensor fan. I'm not sure if thre is enough room between the grill and condensor to fit the fan on my 1976 GMC suburban.

[tucsonjwt]

Does everyone replace the condensor when the compressor is replaced? If so, do you go with a newer parallel flow style? It seems like both styles are available, based on the descriptions on Rock Auto.

http://www.rockauto.com/en/moreinfo....032567&jsn=439

http://www.rockauto.com/en/moreinfo....032567&jsn=437

[tucsonjwt]

From what I am reading elsewhere, even the AC Delco parallel flow condensors are not a direct fit because they are smaller than the original condensor. Does anyone know where I could find a parallel flow in the original size?

[homemade87]

when I was doing my a/c , I like you was not impressed with the parallel flow condenser . They definitely was not a direct fit and was a little smaller . So I decided to use the oem tube one . I flushed it out and when I did my install I made sure all areas around the condenser and radiator were blocked off so no air would go around the sides . Made sure 100% of the air flow went thru the condenser & radiator . Mine works perfect for several years now . I am glad I stayed with the oem one .

[tucsonjwt]

homemade: just so I understand, you used your old existing tube and fin and just flushed it out? You are using 134A? That is what the a/c shop suggested doing, but I just wanted to get the system as reliable as I could.

Based on what you say, I think I will drive my truck for a week or so with the dye they installed, and then have them install a new compressor (probably 4 seasons new unit) with new receiver/dryer/accumulator and orifice tube. This shop said they will guarantee their work for 3 years/36,000 miles for an extra $10, so I just need to make sure that they don't weasel out of the guarantee if the condensor or evaporator fails.

[homemade87]

Originally Posted by tucsonjwt

homemade: just so I understand, you used your old existing tube and fin and just flushed it out? You are using 134A? That is what the a/c shop suggested doing, but I just wanted to get the system as reliable as I could.

Based on what you say, I think I will drive my truck for a week or so with the dye they installed, and then have them install a new compressor (probably 4 seasons new unit) with new receiver/dryer/accumulator and orifice tube. This shop said they will guarantee their work for 3 years/36,000 miles for an extra $10, so I just need to make sure that they don't weasel out of the guarantee if the condensor or evaporator fails.

I installed it just like came from the factory . There are gaps around the edges . I blocked the side edges so the air could not be pulled in from the edges of the condenser instead of pulling thru the condenser and radiator . I used some rubber door seal I got from a truck I parted out . I think I also used some foam to fill the gaps as well . Just make it to where the air is only going thru the condenser . And yes I use the oem tube and fin . The reason for doing this is the tube and fin is not as efficient with r134. So if you can get as much air flow as possible across the condenser the better .

[jdl71]

What actually happened to your compressor? If it grenaded and put chunks of metal in the system then it is recommended to replace the condenser and evaporator. If the clutch just seized you should be able to get by with just a flush. I know this is a bit off your original question, but relevant. I am using 134a with my existing tube and fin and it works fine, and I have an R4 compressor.

[tucsonjwt]

The A/C shop found pieces of metal in the orifice tube, so the compressor failed internally and spit out metal parts. The shop thinks they can flush out the condensor and evaporator and reuse them. Does anyone here agree with that?

[homemade87]

Originally Posted by tucsonjwt

The A/C shop found pieces of metal in the orifice tube, so the compressor failed internally and spit out metal parts. The shop thinks they can flush out the condensor and evaporator and reuse them. Does anyone here agree with that?

The tube and fin is easy enough to flush also the evap core should come clean . If it was a parallel flow I would say replace it . Not so easy to clean out .

I would almost bet if there willing to warranty it they are going to put a filter on it to catch any stray pieces .

[tucsonjwt]

Where would they put the filter? My orifice tube acted as the "filter" in this case.

[Dead Parrot]

IIRC, on my 75, the orifice tube had an integrated filter.

The shop should do a complete clean and flush on the system anyway, to make sure all of the old oil/lube is removed. No telling what a PO might have added.

How old are your AC hoses? It would suck to have them fail shortly after installing the new compressor.

[tucsonjwt]

My A/C hoses where changed in 2002, when I bought the truck and had it converted to 134A. They look OK, but I know looks don't mean anything. I am driving the truck for a week with dye in the system so the shop can check for leaks when I bring it back. If there are no leaks, I will ask them to replace the Compressor, Accumulator/Reciever/Dryer, and orifice tube and see what happens. They showed me the orifice tube and it had a lot of metal shavings on it, so maybe that part has some filtering effect. I think if I have a leak or other component failure in the 3 year warranty period, I will pay for any lost freon and any other defective parts, but no labor.

So far, the best local auto parts store has quoted a 4 Seasons compressor at $313 and an AC Delco compressor at $427. The counter guy I talked with said that 4 Seasons makes the A6 compressors for AC Delco. 4 Seasons warranties their compressors for 2 years, Delco has a 1 year warranty.

I like the idea of an S6, and they are cheaper, but I wonder about long term reliability and have read that some have had to get new hoses and fittings made up to connect to their existing system.

[tucsonjwt]

I got a reference to a Tucson A/C shop with expertise in old vehicle systems, so I think I will visit there in a week or so and see if I can get some advice on what route to take. It sounds like they may be sympathetic to some DIYers.

http://www.centuryautoair.com/faqs.htm

[hatzie]

Originally Posted by tucsonjwt

The A/C shop found pieces of metal in the orifice tube, so the compressor failed internally and spit out metal parts. The shop thinks they can flush out the condensor and evaporator and reuse them. Does anyone here agree with that?

Modern parallel and serpentine condensers have super tiny capillaries in the tubes to increase the surface area. You CAN NOT flush these out.
You CAN flush the OEM condensers on these trucks provided it's just pieces of metal and not the black soupy goo that the Ford compressors were famous for spitting through the system. The original condensers and evaporators in these trucks are open tubes. Be sure to flush all of the lines as well and follow up with an air drying 2nd stage flush to clear all of the first stage flush chemical.

Use a dry inert gas to sweep and pressure test the system. I use welding gas like Argon or ArCO2 mix. Charge the system with the appropriate volume of Ester oil with UV dye. Once it's pressurized you can check with a black light. You'll find most leaks before you spend the $ to vac and charge the system.

You can rent a vacuum pump at AutoZone.
You can spend more time cleaning up the system than you and the shop can afford to have their tech spend...

[tucsonjwt]

Hatzie - thanks for the information.

I think I will drive the truck for a few days with dye in the system, then try to get some free info from the A/C shop. I was debating just getting a new parallel flow condenser and a new evaporator to eliminate the possibility of having those parts go out shortly after installing the compressor.

Condenser: $65-$152
Evaporator: $59-$120
Compressor: $244-$360

I don't know whether to get a new style S6 or old style A6 compressor. The old A6 did last at least the 14 years I have owned it, but I can see benefits in the A6. It looks like AC Delco rebrands the S6 but it only has a one year warranty, while the 4 Seasons new compressors all have a 2 year warranty. I think that this is the AC Delco rebranded S6:

https://www.amazon.com/ACDelco-15-22.../dp/B007QBI4H2

I think it has a smaller pulley and would need a new smaller v-belt.

[hatzie]

The A6 is a heckuva big compressor. Way more than GM needed with R12. It'll make your truck COLD on HFC R134a or HFC R152a and it fits the existing brackets.

If the condenser and evaporator are not corroded flush em then vac and fill with your favorite refrigerant. They don't typically wear out.

If the A6 grenaded you might've been running too high head pressure. As I posted in another thread lbs of R12 doesn't equate to lbs of some other refrigerant and even with R12 you have to be careful as in don't just slam it with X-lbs of R12 because the service manual said that is the charge level. Dynamically charge per the Jungle Eddy instructions I posted in another thread and you shouldn't run into a badly overfilled condition again.
In the South and SouthWest I'd add a High Pressure Cut Out switch to the compressor discharge fitting. Wire it inline between the LPCO and the compressor clutch to cut power when the head pressure rises too much.
Vent temps are actually better with the charge level slightly low to just right. Vent temps rise when you head into overfilled... you burn more fuel and run the risk of slugging the compressor too.

[hatzie]

One point i haven't touched on in any of these conversion threads is being nice to the guy following up after you.
There are labels for the rad support to note the oil type and the refrigerant type.
POE (Polyol Ester)


PAG (polyalkelene glycol)


HFC R134a


There are also unique SAE standard fittings for MVAC charge ports. https://www.epa.gov/mvac/unique-fitt...c-refrigerants