HI,
1984 F250 6.9 Diesel with factory AC.
Bought the truck with empty (factory installed) AC and defective compressor. Installed a reman compressor and had a shop fill the system. AC did work then but quickly lost refrigerant. All parts except the compressor are old (how old I don´t know). Shop says I need a new accumulator, hoses look good.

Since I´m in Germany and have to import the stuff, I´d like to get everything at once. I know that I could throw out everything and buy new parts. What is typically worn/bad and needs replacement in general on these AC systems.

So what else besides the accumulator do you suggest replacing to get the AC working again?

Thanks

 

They simply need to find the leak. If you can keep the gas in it, it will work correct? You may want to find another shop to work on it. Most compressor rebuilders and manufacturers will not warrenty their compressors unless a new accumulator is installed when the compressor is installed. Too late for your situation, it was working ok correct? Just find the leak. They should have a sniffer that can detect leaks. They can also put a dye in the system, charge it back up, let you run it again, and when it runs out again take a special light and find where the dye is leaking out.

 

Lots of info - even videos - out there on finding leaks with such dye:

https://www.google.com/search?q=auto...utf-8&oe=utf-8

 

I know of the sniffer etc.
They just meant that if an AC system was open for months like mine when rebuilding the truck (condenser and compressor were off to get access to the engine) the old accumulator would saturate with moisture from humid air.
That said, I thought better change common failure parts before doing a costly refill with dye and having them check again.
I did search the archives and found orifice tubes get changed a lot during service of an AC system. I have never worked on one before, so I don´t know what to change.

Thanks

 

Is it converted to r134a? That is what we do over here in the states, is to get a kit and convert it over. Most stores over here, even the dollar stores carry the 12 oz r134a cans. And we can buy the dye at the auto parts store. Not sure about the light, probably can get that on the internet somewhere. If I run it awhile, I can sometimes see the dye with the naked eye.

First thing I would do is convert it over to r134a if it isn't already. But I do not know what the rules are over there, gov's are funny about refrigerant sometimes. If you have to pay someone to mess with it, it's going to be a money pit. That goes for the whole truck really.

P.S. Another method is to brush soapy water on the fittings and such where you think it might be leaking. Look for any oily areas, there is oil that runs around with the refrigerant, so you can sometimes see dirt sticking to a oily place around a fitting somewhere. I will tell you many times they like to leak right at the shrader valves where you fill the gas.

I have also had the plastic protector caps that keep dirt out of the shrader valves cause the gas to leak out. Took me awhile to find that one. Left the caps off, no more losing gas. I put rubber caps on it instead, no more problems.

 

You should replace the receiver/dryer (accumulator) and the orfice tube along with the compressor. As far as leak points it is usually the o rings on the connectors that leak or the service ports. The only other part that is fairly prone to leak is the condensor which will usually be indicated by a wet or oily spot on the condensor coils. The hoses and the evaporator are not usually the cause of leaks unless they have been damaged at some point.

 

I got to ask why replace the compressor if the system was only open to access something else like replace the motor?
I can see replacing the dryer because of what was said of pulling in moister.
The orifice tube is a questionable again why as it is not hurt left out in the open. Now it is under $5 so why not replace it or at least pull it and check for junk.
It is just my thinking and would like to know why is all.

My system was working / sealed when the PO pulled the motor and opened it up. It has been open since I got the truck in Dec 2015.
I have to replace the condenser, water pump hit it when they pulled the motor and pinched a tube (no flow when tested), did not puncture it.
The dryer will be replaced and the orifice tube because of how cheap it is.
Oh I will be replacing the compressor only because I don't want to use that big ugly York.

I think I also have to replace the hoses as I cant remember if I have them or not. So far I have not found them thru the normal parts places so I may end up making them.
Dave ----

 

I meant if you are replacing the compressor you should replace the dryer and orfice tube as well, however me personally if the truck has sat and/or been without freon for years I usually do go ahead and replace the compressor due to their tendency to leak through the shaft seal.

 

You can discuss what should or shouldn't be done, but the thread starter had the system working, even though the people who did it did not follow normal procedure. So lucky him, it's working, it just has a leak somewhere.

If you pull a vacuum on the system for half a day or so, and everything is in working order, you can usually get most of the moisture out of a system that has been sitting around for a long time. That along with a new dryer.

 

Ok got it I though you would replace the compressor anytime the system was opened.
I want to go with a Sanden compressor when the time comes to get my system running.

True they should have found the leak and told the owner what it was, what it would take ($$) to fix and let them decide what they want to do and not say just replace the dryer.
If someone wanted to pressurize the system to see if it holds psi you can use Nitrogen.
You would still need to pull a vacuum before charging but sometimes you may not be able to hold vacuum because the compressor seals don't work that way even if that is the way to test a system.
Dave ----

 

The A/C compressor uses a ceramic mechanical seal, it will hold vacuum as well as pressure. It is better to pressurize the system for testing, since if you pull a vacuum you can only put about 14psi or less on it depending on where you live, you are putting atmospheric pressure on it. With a pressure testing system you can put 150 psi on it.

It's a big no no, but I have done it twice now with no ill effects. I have an adapter to go from 134a fitting to my air compressor, I have put compressed air on two of my systems doing some testing. I then vacuumed them out really good and charged them, and they are still working years later.

 

Not sure what happened to the old compressor. If it had a major problem, Was the system flushed? Could possibly be trash in the orfice tube. Have seen this more than once.

 

I'll have to remember this, at work we used Nitrogen. I have a CO2 tank at home, it is a dry gas also. Thanks for the tip. Never thought about using shop air.

 

And you hit on why you don't want to use shop air .... it is not dry air like the Nitrogen & CO2.
Now I will have to remember the CO2 as I also have a tank at home I used with my MIG welder before going with Argon mix.
Dave ----

 

You shouldn't use it, it introduces moisture in the system. But it's all I have at home, so I take the risk.