New a/c compressor - Page 2 - PeachParts Mercedes-Benz Forum

tangofox007 · #16 05-19-2009, 12:36 PM

Quote:

Originally Posted by leathermang

Once again ah-kay is willing to overlook certain facts which have been learned the hard way..

Ah-kay's "willingness" is probably rooted more in necessity than in virtue!!!

Quote:

Originally Posted by ah-kay

I am not promoting R134a, I am just stating the facts. Find me a new car using R12.

That's precisely the type of argument that someone who doesn't have alll the facts would make. As a refrigerant, R-134a is significantly less capable than R-12. R-134a systems work acceptably because they were designed to overcome the deficiencies of R-134a. An R-12 system does not have the advantages of the increased heat transfer capacity that was engineeered into the R-134a systems, so you cannot simply change the refrigerant type to a less capable version and expect good results. Any notion that you can simply defies the laws of physics.

For someone who is overhauling their a/c system, the added cost of using R-12 is small when compared to the overall investment being made. The payoff is an a/c system that will work well as compared to one that will be a marginal performer when the ambient temp exceeds about 85*F.

ah-kay · #17 05-19-2009, 01:06 PM

http://www.id-usa.com/how_to_faqs_retrofitting.asp

Do yourself a favor and read the FAQ site from a reputable company in A/C if you want to use R134a. If you go to Walmart or most shops, all you see is products from this company, Interdynamics Corp. If anyone or any physicists who disagrees with the FAQ on the physics of the refrigerant, please contact the company and correct them.

Graplr · #18 05-19-2009, 01:08 PM

Quote:

Originally Posted by ah-kay

I am not promoting R134a, I am just stating the facts. Find me a new car using R12.

I'll just state facts too.

Find me a car before 1992 that was designed to use r134a.

R134a won't work as well as R12 will in an R12 designed system.

R134a will no longer be used in Europe in new cars in a few years just as R12 is no longer used in new cars in the US.

You have stated that R134a is 'good for the environment' in another thread here http://www.peachparts.com/shopforum/showthread.php?t=252067&page=2 in post #23. R134a is not good for the environment, it harms the environment, just as all manufactured freons do.

By stating that you want to tell others "that R134a is comparable to R12 and is good for the environment" it shows that not only are you promoting r134a but your ignorance as well.

::matthew · #19 05-19-2009, 01:32 PM

how would I know if my 1YO or so Delco R4 compressor was designed to work with R134a?
just the part # or is there some obvious differences in the look/design.

KrautWagonGTI · #20 05-19-2009, 01:36 PM

F**k the environment, I just want cold a/c

It's better than my sweaty a** stinking the place up lol

tangofox007 · #21 05-19-2009, 01:41 PM

Quote:

Originally Posted by ah-kay

http://www.id-usa.com/how_to_faqs_retrofitting.asp

Do yourself a favor and read the FAQ site from a reputable company...

That FAQ was clearly written by the marketing and legal departments, not the tech dept. If good science supported their claims, they would be happy to show the data. Instead, they serve up some carefully crafted generalities about how some unspecified number of customers haven't complained and about how some duct temperatures might be warmer.

R-134a in an otherwise unmodified W123 won't perform nearly as well as R-12. There are those of us who have already learned that lesson. And others, apparently, still hankering to pay tuition in the school of hard knocks.

tangofox007 · #22 05-19-2009, 01:43 PM

Quote:

Originally Posted by ::matthew

how would I know if my 1YO or so Delco R4 compressor was designed to work with R134a?

Unless it sat on a shelf for a long time, it's almost certainly R-134a compatible.

leathermang · #23 05-19-2009, 01:49 PM

Krautwagon...
If your Delco says R134a on it you should be in good shape...
You did not put where you live in the upper right section of the post...which sometimes makes a difference in answers we give...
I say ' in good shape' of course with the caveats mentioned by several already... if all the rest of your system is in good shape... things like the fins clean and straight...and you do not live in a particularly hot and or humid section of the country the R134a may do you a fine job...
One item I would suggest cleaning.....and DWMorrison in the archives has a great thread on it.... is the EVAPORATOR FINS.... this is hardly ever mentioned... but can make or break a system at the edge ...or on R134a.... those fins can greatly restrict air flow at the most important point... even when all the rest of the system is working fine... not easy to get to and clean... but well worth the effort when going with R134a.

thayer · #24 05-19-2009, 06:16 PM

http://www.facebook.com/album.php?aid=83976&id=601553061&l=6d368da55e

Here are some pictures of my compressor and dryer and blower.

where is the monovalve?
Where is the fuse to the compressor that is not in the fuse box?
Where is the Aux Water Pump?

My symptom is that the compressor is not getting power.
And my pushbutton controller is blowing out. (I resoldered it enough to reengage the blower and switch between hot and outside air)
When I find out why its blowing my pushbutton, I'll install a new one

panZZer · #25 05-19-2009, 06:23 PM

Anybody know the thread of the texas guy making the kit to use the newer style compressor on the 617

Matt L · #26 05-19-2009, 08:31 PM

Quote:

Originally Posted by ah-kay

http://www.id-usa.com/how_to_faqs_retrofitting.asp

Do yourself a favor and read the FAQ site from a reputable company in A/C if you want to use R134a. If you go to Walmart or most shops, all you see is products from this company, Interdynamics Corp. If anyone or any physicists who disagrees with the FAQ on the physics of the refrigerant, please contact the company and correct them.

Excuse me while I have a good chuckle at Interdynamic's expense.

There is no need to correct them. I'm sure that they care about the veracity of their FAQ just as much as they care about the quality of the products that they sell, and that can't be any further than the legal dept. Their stuff is all junk.

Jerry Cohen · #27 05-23-2009, 10:15 PM

Quote:

Originally Posted by ah-kay

There is no problem using R134a.

1) Fill the compressor with 8oz of Ether oil. Pag oil is OK but it is better with Ether as the system was using R12 before and has mineral oil. Ether Oil mixes better with the old oil unless you can purge the mineral oil completely.

2) Put 2 oz of oil in the rec/drier. It is not necessary but some people recommend it.
3) Pull vacuum down to 20-25 hg or better and make sure it holds for a few hours, or overnight.
4) Charge with R134a.

I wish hacks wouldn't give advice like that, here we go again. Our resident a/c expert strikes again. Armed with Wally world and Harbored Frrieght instructions, and no real world experience working on hvac systems. At least not in an enviorment where he would be on the hook for his bad advice.

He is wrong on all counts, for example, the vacuum measurment he gives is off. Unless you are using a cheesy air operated vacuum pump that can only muster 20-25 hg.

He might not know that moisture will NOT boil off at 20-25 HG.

Mixing of oils in the way he suggests is a sure way to form acid and cause black death to all those expensive parts. Don't listen to this guy.

The amount of oil is specific for each car and/or compressor used, not what some guy posts on the internet as the correct amount for everyone to use.

There are lots of problems with using R134a in a R12 system, the gas is the cheapest part of a proper a/c repair and R12 will cool best, hands down. Don't listen to this guy.

Geez, a little knowledge is a dangerous thing. Especially if it is passed on as absolute fact.

People, do yourselves a favor, and look this stuff up. Don't listen to this guy.

leathermang · #28 05-24-2009, 03:59 AM

Jerry, AMEN !!! Thanks for saying it in such a clear and direct fashion.

rscurtis · #29 05-24-2009, 10:03 AM

A friend of mine has an 84 SD which had 134 in it when he bought it several years ago. It never cooled that well, and the refrigerant charge amount had to be right on the money. It also put a lot of load on the compressor in hot, humid conditions. So, he installed a rebuilt compressor, flushed the system, and went back to R12. Much better on every account. My '83 had never been converted to 134 and after repairs of a few leaks works perfectly.

derburger · #30 05-24-2009, 11:21 AM

Quote:

Originally Posted by rscurtis

A friend of mine has an 84 SD which had 134 in it when he bought it several years ago. It never cooled that well, and the refrigerant charge amount had to be right on the money. It also put a lot of load on the compressor in hot, humid conditions. So, he installed a rebuilt compressor, flushed the system, and went back to R12. Much better on every account. My '83 had never been converted to 134 and after repairs of a few leaks works perfectly.

Same situation with my 300cd, and I went back to r12 from r-134a last summer. Now the A/C cools just as well if not better than a modern car.

The gas isn't the most expensive part of the system. I bought r12 for $17/LB last summer and $15/LB this summer.

If you took AHKAYS advice your compressor would hydrolock, A/C system get the black death. Reading instructions on the harbor freight A/C manifold gauge kit and the walmart r-134a can only makes you an expert on blowing yourself/your car's A/C system up.