How can I have AC repaired without being taken to the cleaners? - PeachParts Mercedes-Benz Forum

TedsBenz · #1 03-28-2008, 11:40 PM

My recent aquisition, an 84 300sd, had its AC converted to R134 according to the previous owner. He said he thought it had a small leak as it was not cooling well by the end of last summer. When I set the climate control for full blast AC I do not hear the customary click of the compressor kicking in, or see a change in idle. This what I'm use to hearing in my other vehicles. The air temp coming out the vents is whatever the temp is outside.

Do I walk into a MB repairshop and say, "make it work, again!"????

I need AC. but she is 24 years old...I don't want the repair to exceed the value of the car.

BTW, the heater temp control works great as do the blower speed/auto controls. The pods are stuck so that I get great defrosters....and some air out the side vents.

Any info would be appreciated.

1984 MB 300SD 383,280 miles...and just passed state inspection!

bustedbenz · #2 03-29-2008, 12:10 AM

Quote:

Originally Posted by TedsBenz

Do I walk into a MB repairshop and say, "make it work, again!"????

I need AC. but she is 24 years old...I don't want the repair to exceed the value of the car.

1984 MB 300SD 383,280 miles...and just passed state inspection!

Those two lines are just about incompatible... walking in and saying "Fix it" is about the most expensive option there is. I'd say your choices are either DIY (i'm sure somebody here can figure out what exactly you need to do) or just use 4-60 air conditioning.

leathermang · #3 03-29-2008, 01:55 PM

Quote:

Originally Posted by turbobenz

Try using your finger nail and depressing the little shrader valve onto of of the ac hose near the valve cover, if air comes out you should be ok.

If it is completely gone, then there is air in there, hence moisture, and it should be evaucated and done the right way otherwise it would barely be worth your time

Ok.. first, people should use eye protection when dealing with AC stuff...
and you should also wear gloves... so your fingernail should not be available ... the warning on the can says that skin exposure can result in frostbite.... easy to avoid... use something else handy to depress that valve core if you do that...

While it seems that the AC system is always under pressure... thus unless totally leaked out would not have acquired any moisture due to a leak.... the actual physics are different since it is a dynamic system... and the industry wide agreed upon position is that if you have a leak you should assume that your system is contaminated with moisture.... particularly since that is very damaging ( water and stuff combine to make acid ) to certain places inside your system...

vstech · #4 03-29-2008, 08:43 AM

http://dieselgiant.com/repairyourac.htm
not too bad expensive...

jtwangler · #5 05-01-2009, 04:58 PM

Quote:

Originally Posted by vstech

http://dieselgiant.com/repairyourac.htm
not too bad expensive...

This is great but I have to change out the low side hose (I think that's what its called) on my 85 w123 Euro wagon. I don't have a picture of this but it runs from the low side port back towards the firewall and I believe it must run through and go to the expansion valve but I'm not sure. Does anyone have any experience with this? How do I change this hose?

C Sean Watts · #6 05-01-2009, 05:04 PM

FS: R12 Freon

Graplr · #7 05-01-2009, 05:11 PM

AC work is pretty simple. I had never worked on an AC system before and I totally rebuilt mine for probably around $300 (I didn't need a new compressor and the only real issue was a leaking condenser). Of course I bought some equipment that doesn't go into that price.

You have all the help you need right here.

jtwangler · #8 05-01-2009, 05:16 PM

Quote:

Originally Posted by Graplr

AC work is pretty simple. I had never worked on an AC system before and I totally rebuilt mine for probably around $300 (I didn't need a new compressor and the only real issue was a leaking condenser). Of course I bought some equipment that doesn't go into that price.

You have all the help you need right here.

How many hours did you put into your work? and can you help me identify the hose and where it goes?

Cr from Texas · #9 05-01-2009, 07:18 PM

I after endorse the position taken by leathermang.

A cheap quick fix will eventually become an expensive more detailed repair if anyone want to keep using the AC.

Plan on any DIY repair taking a few hours to accomplish. The first two should be spent doing searches and reading. I've done that and I've started. New R4 compressor, drier, and expansion valve can be purchsed for about $300+. I'm flushing the system. Removing the old hoses and taking them in for rebuilding. It's not hard to find a shop that can replace the barrier hose and reuse the fittings. Much cheaper and probably not too far from the quality of all new hoses. I will reasemble and evacuate to do the first check for leaks. Then refill with 4 oz R22 and nitrogen. No, I don't have either in my garage but it's not too hard to find an AC shop to put in the 4 oz R22 and then go to a tire shop that uses nitrogen to pressurize the system to 70 psi static. Rent an electronic leak detector. Fix all leaks, vacuum, refill with R12. I'm sticking to R12 and mineral oil - that's what the system was designed for and that will provide the best cooling.

After and hour or two of reading (much of it posted by leathermang), you will probably conclude that the right way is the best way.

Wrong way --- you might as well spend nothing and roll down the windows. That's the only cheap fix.

ah-kay · #10 05-01-2009, 07:35 PM

Quote:

Originally Posted by Cr from Texas

I've done that and I've started. New R4 compressor, drier, and expansion valve can be purchsed for about $300+.

No, I don't have either in my garage but it's not too hard to find an AC shop to put in the 4 oz R22 and then go to a tire shop that uses nitrogen to pressurize the system to 70 psi static. Rent an electronic leak detector. Fix all leaks, vacuum, refill with R12. I'm sticking to R12 and mineral oil - that's what the system was designed for and that will provide the best cooling.

I really do not want to post but I just cannot help it. I don't have $300+ to spare. I do not want to go to a tire shop and pay them to use the N2, I do not want to rent an electronic leak detector at a cost. I just want to have cold air on my 20+ year car which costed $700 to buy.

I just offer a cheap solution, it is the readers perogative to take it or otherwise.

leathermang · #11 05-01-2009, 08:28 PM

Quote:

Originally Posted by ah-kay

I really do not want to post but I just cannot help it. I don't have $300+ to spare. I do not want to go to a tire shop and pay them to use the N2, I do not want to rent an electronic leak detector at a cost. I just want to have cold air on my 20+ year car which costed $700 to buy.
I just offer a cheap solution, it is the readers perogative to take it or otherwise.

I do not blame you for being lazy with regards to the AC equipment on your car. It is pain to have to follow so many rules in order to get the physics correct.
I do not blame you for not wanting to spend money on your car. It is YOUR CAR.

But to post a 'cheap' lazy short term solution holding it out to others as a legit fix for their AC systems is behavior totally LACKING in CLASS and empathy for others.

ah-kay · #12 05-01-2009, 08:42 PM

Quote:

Originally Posted by leathermang

I do not blame you for being lazy with regards to the AC equipment on your car. It is pain to have to follow so many rules in order to get the physics correct.
I do not blame you for not wanting to spend money on your car. It is YOUR CAR.

But to post a 'cheap' lazy short term solution holding it out to others as a legit fix for their AC systems is behavior totally LACKING in CLASS and empathy for others.

I am sorry if my post offended any anyone. As I have said this is "How can I have AC repaired without being taken to the cleaners?". And it is the perogative of the reader to follow or otherwise. It may not be the 'politically correct' way to do things but it gets the job done.

Disclaimer: it is illegal to vent R134a

It is illegal under Section 608 of the Clean Air Act to knowingly vent substitute refrigerants during any service, maintenance, repair or disposal of an appliance.

So seek professional help and be prepared to be taken to the cleaners.

leathermang · #13 05-01-2009, 09:53 PM

Quote:

Originally Posted by ah-kay

As I have It may not be the 'politically correct' way to do things but it gets the job done.

I am not politically correct.

But attempting to be physicscally correct is the only way to have a chance that the system will give long ( and thus inexpensive ) service.
I know that is not a word but it just seemed to fit....

Jerry Cohen · #14 05-01-2009, 10:57 PM

Quote:

Originally Posted by ah-kay

I am sorry if my post offended any anyone. As I have said this is "How can I have AC repaired without being taken to the cleaners?". And it is the perogative of the reader to follow or otherwise. It may not be the 'politically correct' way to do things but it gets the job done.

Disclaimer: it is illegal to vent R134a

It is illegal under Section 608 of the Clean Air Act to knowingly vent substitute refrigerants during any service, maintenance, repair or disposal of an appliance.

So seek professional help and be prepared to be taken to the cleaners.

No offense taken, except for the taken to the cleaners part.

Yes, it's illegal and also wrong to vent R134, the last time I checked being politically correct had nothing to do with following the law and using common sense.

You forgot to mention the venting gas into the engine compartment of a running vehicle can create deadly mustard gas in some cases. You probably didn't know that, huh?

I just don't want an innocent person to read your posts, think that what you say is 100% correct, and get hurt.

Maybe you should edit your posts. Someone will probaly get frostbite, or much worse. Do you know what mustard gas does to a person?

You know that it can easily be fatal, right?

All this so you won't sweat?

popscat · #15 05-04-2009, 12:38 AM

just got thru reading the tread on a/c repair no one says what the high side pressue should be and also the low side. the condenser can blow apart with to much high head pressure if the switch is bypassed. is the a spec on pressures?????? anyone use frezze12? relay in the climate control can cause this guys problem cracked solder joints burned contacts etc. i have rebuilt my control with ssr instead of the old mech. relays