Purchasing a Condenser

[Graplr]

I've discussed my A/C woes on here in a few different threads. To recap, the A/C has not worked since at least the A/C season of 2004 (PO said it never worked in the 2 years he owned it). I purchased it in spring 2007 and started troubleshooting it about a month ago.

Here is what is known:
R134a conversion sticker from 2001.
Compressor manufacture date 2000. It is a Four Seasons. Thus can safely assume it was new during the retrofit.
Expansion valve appears newer and am assuming it was new at the same time.
Compressor works. I ran a jumper wire and it spun freely for a few seconds.
No pressure on manifold gauges due to no refrigerant in system due to a leak in the condenser.

I found the leak in the condenser by adding R134a to the system. Within a minute I heard a hissing coming from the front of the car. Found it to be the condenser. In my 300SD both condenser connections are on the driver side. The leak is coming from the passenger side, thus it must be the condenser itself.

I am going to replace the condenser next. I can't find a used one locally, thus I will be purchasing a new one. Since parallel flow condensers cost much less than new OEM condensers and are more efficient I have decided to purchase a parallel flow one.

From this What's the biggest condenser that fits in 126?
it seems other SD owners went with a 24.75 x 15.5. I'm having trouble finding one with these dimensions.

I checked ackits http://www.ackits.com/merchant.mvc?Screen=CTGY&Store_Code=01&Category_Code=Parallel
and found one at 24 x 14 for $108.

acsource has a 26 x 14 for $102. http://www.acsource.com/index.asp?PageAction=VIEWCATS&Category=212

Found one on ebay http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=370049536803&ih=024&category=33547
at 24 x 14 for $90.

Assuming they all are the same buying the one on ebay would be the cheapest. I plan on buying the mounting kit from acsource on the link above. It is only $5 and would save me a lot of hassle of running back and forth to the store. I would also buy some new o-rings from somewhere.

Question about the fittings. Reading through the thread I linked, it seems I need a #8 fitting to a #10 hose. The bottom fitting is a #6 fitting to a #8 hose. Where can I buy these? I've been told to find a hydralics shop to make the hose, but I would assume they wouldn't have the fittings itself?


Now after I get the condenser in, I plan on flushing the rest of the system. Putting in a new reciever/dryer from ********az here http://www.***************/search/product.aspx?sid=swaisn45ylh3wd45uw4z1h45&makeid=800016@Mercedes&modelid=1194038@300SD&year=1984&cid=24@AC%20%26%20Heat%20-%20Climate%20Control&gid=6972@Receiver%20Drier/Accumulator

If I flush everything, I will need to add oil to the system, correct? How will I add oil to the compressor if I don't take it off? What oil should I use?

Then I will rent/borrow a vacuum pump. Then put r134a back in and see how it performs!

PS- I live in MN and don't need absolute maximum cooling. I just want to get the dang system working!

So any advice on the condenser?
How about the custom hoses?
How about flushing the system?
Advice about the oil in the compressor?

Thanks!
-Ryan

[dannym]

I would think any parallel flow condenser that will fit will do.

What type of AC compressor do you have? You don't flush the compressor. I just added the oil to the filter dryer.
I have the R6 I believe, the big hockey puck type.

Danny

[thorsen]

I rebuilt the AC system in my 250C this winter. I recommend http://www.rayeveritt.com/ for fittings.

I bought a hose crimper off eBay for $100 and made my own hoses. It was easy and although the link I provided will custom make hoses for less than I paid for my crimper, it was an enjoyable job for me.

[Graplr]

Originally Posted by dannym

I would think any parallel flow condenser that will fit will do.

What type of AC compressor do you have? You don't flush the compressor. I just added the oil to the filter dryer.
I have the R6 I believe, the big hockey puck type.

Danny

Danny,
Thanks.

It is an R4 Four Seasons.

So then I should not add any oil after I flush the system except to the filter dryer?

[Graplr]

Originally Posted by thorsen

I rebuilt the AC system in my 250C this winter. I recommend http://www.rayeveritt.com/ for fittings.

I bought a hose crimper off eBay for $100 and made my own hoses. It was easy and although the link I provided will custom make hoses for less than I paid for my crimper, it was an enjoyable job for me.

Thorsen,
Thanks for the link. When I get the condenser I'll see exactly what I need and then most likely take it to a shop to crimp the hoses. I don't think I will purchase a crimper myself.

[rrgrassi]

You can flush a compressor, but only with the type oil you plan on using. Our systems need 6-8 oz of oil. A little too much is not a problem since the R4 does not have an oil sump like the A-6.

http://www.ackits.com Has lots of automotive A/C info.

[Graplr]

Should I skip the flushing all-together since I'm using the same compressor and the same refrigerant?

I assumed (don't know if it is correct or not) that since there is a large leak I should flush it. Maybe I don't need to???

Can I just change the condenser, add new fittings and hoses, put a new drier in (with oil), add r134a and be good to go?

[Matt L]

Are you sure that you know what kind of oil is in there now? If not, you should flush the entire system. I'd recommend using the newer DEC-PAG (46) oil in the system.

If you do flush the system, you should add oil to all of the parts. Figuring out how much oil remains in the compressor is the hardest part, and you may have to guess. You should try to get as much out as possible (after flushing) then add again. Do not use solvent or refrigerant to flush the compressor. Use new oil only. Flush all lines unless they contain mufflers. If you think any lines with mufflers need flushing, either have the muffler removed or replace the line.

If you don't flush the system, you have no idea how much oil remains in the system. You can guess, of course. Also you need to work fast, and not leave any unflushed lines open to the atmosphere, as the oil is hygroscopic and forms acid when mixed with water.

In addition to the dryer, you should remove the expansion valve to flush the evaporator, then install a new valve.

[rrgrassi]

Replace the expansion valve also. It is a good idea to flush the system. When I ran R134a in my car, I used the thicker GM spec PAG oil, since the R-4 is a GM design.

The Hoydon (Hancock Ind) compressor is the redesign. I paid $220 for mine at a local NAPA. I use the "junk" Freeze-12 with BG Frigiquiet oil. I've used this setup for a year now. So far so good. R-12 would be ideal, but it costs too much for me personally.

My Nissan P/U has been running Freeze-12 for the past 5 years with no problems.

[Graplr]

Okay, that answers the whether I should flush question.

Specifically, how do I flush the compressor and with what (assuming I leave it on)?

[rrgrassi]

You have to remove the compressor from the car and flush it with the new oil you intend to use. Use an electric of battery operated drill to spin the compressor.

The link to ACKits above will have step by step info on flushing a compressor in their FAQ forum.

[derburger]

How difficult/worth it is it to remove/replace a compressor? I have a working r-134a system with a new compressor from 2000. I don't know what oil is in it, and I'm de-converting to r12 in a few weeks, I might get a new PF condenser if I decide it's worth the extra cost. I have a jack, stands and the basic tools for the job. Is it pretty straightforward, or are there many "gotchas"? How long does it normally take to R&R the compressor?

[tyl604]

I would take the middle route. Do all the mechanic work yourself; then have the indy vac the system and add the refrigerant.

[Graplr]

Update:

After a lot of research I ended up ordering this from ACKITS:

24x14 Parallel Flow Condender
#6 Female 90 degree fitting
#8 Female 90 degree fitting
2ft of 6 and 8 hose
2 8oz bottles of BVA Auto 100 (POE) compressor oil
NYLOG O-ring sealer


I ordered this from Autohasauz:
Reciever/Drier
Expansion Valve
O-ring kit

Need to additionally purchase:
Flush in a can
Adapters to fit new hose fittings to compressor line and drier line.


Here is my new plan.

1- Take old condenser out
2- Install new condenser
3- Take to shop to crimp/fit new hoses to drier and compressor line
4- Take off compressor and flush with oil
5- Take off old expansion valve and drier, flush throughly
6- Put compressor back on
7- Put new expansion valve and drier on
8- Install new o-rings with sealant and seal up system
9- Rent vacuum pump or take to shop to pull vacuum
10- Fill with r134a


How does this sound?

Questions:
When fitting the #8 fitting from the condenser to the compressor line, is it possible to splice it into the existing line? Or do I have to run the new line all the way to the compressor?
Same question for the #6 line running to the drier.

[bobodaclown]

Originally Posted by Graplr

Here is my new plan.

1- Take old condenser out
2- Install new condenser
3- Take to shop to crimp/fit new hoses to drier and compressor line
4- Take off compressor and flush with oil
5- Take off old expansion valve and drier, flush throughly
6- Put compressor back on
7- Put new expansion valve and drier on
8- Install new o-rings with sealant and seal up system
9- Rent vacuum pump or take to shop to pull vacuum
10- Fill with r134a


How does this sound?

Plan sounds/looks solid.