thanks Mike! I redid the air conditioning pump on my truck due to failed clutch.

[CSM]

Between Mikes article and a YouTube video by ericthecarguy or whatever his channel is I got it all done.

Thanks for putting the tables for pressures up and the how to info.

If anybody needs a good pump with a bad clutch, let me know.. I don't have a use for it and will probably trash it soon.

[Mopar1973Man]

Not a problem. I'm glad my information helped out.

[diesel4life]

CSM,did your a/c work good other than the bad clutch? I am now dealing with this same problem. Clutch is on its way out. Normally I would just replace the compressor but my AC works so good I'm having a hard time dropping the coin to open everything up. Technically if you do the compressor the drier needs replaced. Then a vacuum needs pulled on the system before charging so that's another expense because I dont have the proper equipment. Really contemplating the clutch job on this one. I'm going to dig into my FSM this weekend to see what it entails before I make a decision.

[Mopar1973Man]

Either way your going have to pull the compressor to do the clutch work. I really doubt you'll have the room to pull it.

[Wild and Free]

Compressor removal on a functioning system doesn't warrant a drier change unless it is open to the elements and high humidity for a while or if the compressor failed. If you tape off the lines as soon as you pull the comp off you would be fine.

 

But yeah not having the correct equipment makes it tough. really only need 3 main things and could get all fairly cheap, Vacuum pump either electric or air venture if you have a good enough air compressor, digital scale for accurate Freon load and a gauge set.

 

Although on the newer systems we only use the gauges as a reference and mainly for troubleshooting and not charging anymore. The newer ac systems are becoming more and more complicated and extremely touchy as much as a couple ounces one way or another on 10lb systems can make or break you which is why an accurate digital scale is so important, charging ac systems using pressures is old school for older systems and may get you going but I guarantee it is not going to be as good as having the exact amount the system is designed to run.

[Mopar1973Man]

Most all vehicles today have a label under the specifying weight of freon.

 

 

Also most vehicles that are 1996 and newer are R134a freon systems and all run the same pressure range for the most part. 30-40 PSI on the lo side.

 

 

The whole trick is getting enough freon to keeping the compressor locked and not cycling without over doing. Too little will cause compressor clutch damage with constant cycling in and out. Then over charging will decrease performance of the A/C because higher the lo side the warmer the air will become. Like back in the day R12 for refrigerator was 2-5 on the lo side A/C was 35-40 on the lo side.

 

[CSM]

The factory service manual says to pull the pump on diesels and had the procedure to change the clutch. Gas trucks can get by without pulling the pump.

However... due to time I just did the whole pump.

Edited April 23, 2015 by CSM

[diesel4life]

Compressor removal on a functioning system doesn't warrant a drier change unless it is open to the elements and high humidity for a while or if the compressor failed. If you tape off the lines as soon as you pull the comp off you would be fine.

 

But yeah not having the correct equipment makes it tough. really only need 3 main things and could get all fairly cheap, Vacuum pump either electric or air venture if you have a good enough air compressor, digital scale for accurate Freon load and a gauge set.

 

Although on the newer systems we only use the gauges as a reference and mainly for troubleshooting and not charging anymore. The newer ac systems are becoming more and more complicated and extremely touchy as much as a couple ounces one way or another on 10lb systems can make or break you which is why an accurate digital scale is so important, charging ac systems using pressures is old school for older systems and may get you going but I guarantee it is not going to be as good as having the exact amount the system is designed to run.

On replacing the drier, the compressor warranty will be voided if they are not changed in pairs. They are relativy cheap anyway, and being my system is several years old if I'm doing one it only makes sense to do both.

How expensive are the vaccum pumps? Ive honestly never priced them, but as many vehicles as we have (including immediate family) it may well be worth the investment if they're not terribly expensive. Ive always hated sending my vehicles off for a/c work as it is the only job I'm really not set up to do. Looks like Ive got some homework to do.

[diesel4life]

What about these cheapy Pittsburgh vac pumps? Obviously it wouldn't hold a candle to an industrial 2 stage nor would it hold up to regular use but how about the 1 or 2 jobs a year I would use it for? For $100 it would about pay for itself the first time I didn't have to take a vehicle in for a/c work. Anybody have any experience with these little pumps? I honestly never knew they sold such small pumps.

http://m.harborfreight.com/25-cfm-vacuum-pump-61245.html

Edited April 23, 2015 by diesel4life

[CSM]

I went to auto zone and rented one for free.  

 

The cheapest and best reviewed ones I've found were on Amazon Prime for 89 or so for a nice pump.  

[Mopar1973Man]

http://m.harborfreight.com/25-cfm-vacuum-pump-61245.html

 

I've got the very same vacuum pump but by a different name.

[CSM]

http://www.amazon.com/Single-stage-Rotary-Vacuum-R410a-Refrigerant/dp/B00BXMRP4I/ref=sr_1_4?s=automotive&ie=UTF8&qid=1429844315&sr=1-4&keywords=vacuum+pump

 

http://www.amazon.com/FJC-6905-1-5-Vacuum-Pump/dp/B002DMZA2G/ref=sr_1_6?s=automotive&ie=UTF8&qid=1429844315&sr=1-6&keywords=vacuum+pump

 

http://www.amazon.com/Robinair-15115-VacuMaster-Single-Vacuum/dp/B005CO9FDW/ref=sr_1_1?s=automotive&ie=UTF8&qid=1429844315&sr=1-1&keywords=vacuum+pump

 

I haven't tried these, but there are a lot of options.  Still, its hard to beat free from Auto Zone if you are just doing one vehicle.  

[Wild and Free]

Air venture pumps are even cheaper if you have a compressor that would have enough cfm to run one for a bit.

[Mopar1973Man]

I like to hold a vacuum on a system for extended period of time to allow all moisture to boil out to a vapor and allow the vacuum pump to vent it out. That's why I don't really like the compressed air type because most air compressors could keep up for over 15-20 minutes of solid pumping. Where a electric pump can withstand 15-20 minutes without even slowing down.

[diesel4life]

http://www.amazon.com/Single-stage-Rotary-Vacuum-R410a-Refrigerant/dp/B00BXMRP4I/ref=sr_1_4?s=automotive&ie=UTF8&qid=1429844315&sr=1-4&keywords=vacuum+pump

 

http://www.amazon.com/FJC-6905-1-5-Vacuum-Pump/dp/B002DMZA2G/ref=sr_1_6?s=automotive&ie=UTF8&qid=1429844315&sr=1-6&keywords=vacuum+pump

 

http://www.amazon.com/Robinair-15115-VacuMaster-Single-Vacuum/dp/B005CO9FDW/ref=sr_1_1?s=automotive&ie=UTF8&qid=1429844315&sr=1-1&keywords=vacuum+pump

 

I haven't tried these, but there are a lot of options.  Still, its hard to beat free from Auto Zone if you are just doing one vehicle.

I was actually looking at Robinairs website last night after talking to my cousin. I'm sure the pumps are made by someone else but if Robinair will put their name on it it should be a decent pump for light duty use.

I agree with your assessment on the free use from Auto zone and that may be the best way for me to go as well. But for $100 (plus possibly a set of scales) its quite tempting to pick one up to be able to do mine and my immediate families a/c work for the future. Ive already got a manifold for diagnosing and charging.

Thanks for the suggestions guys.

[Mopar1973Man]

Like myself I pick up the tools because there is no one around to do A/C work. So now I make a bit of income from doing A/C work.

 

[diesel4life]

Like myself I pick up the tools because there is no one around to do A/C work. So now I make a bit of income from doing A/C work.

Ive not been able to find a local shop that does good a/c work either. So its either take your chances and let a hack work on your vehicle or suck it up and take it to the dealer. The former option is more costly but they are the better bet of the two, at least they can be held accountable for their work. I have a friend that owns an automotive shop with the necessary equipment but he has been closed up for health reasons. The only other local shop here we tried a few years back and it didn't turn out well. It was for the wife's a/c compressor, I bought all the parts and brought them in and the car. They told me to leave it as it wouldn't be til later that afternoon. An hour and a half later they called and said it was done. It was OK for the first week but when the weather got hot it was hardly sufficient. We ended up paying the dealer to draw the system down and recharge it as that was the only way they would work on it and the local shop that did the work kept pushing us off.

Its hard to find people to do the job you pay them to do.

[Wild and Free]

Having done ac for 20+ years some times ac systems can be a real pain in the but, can't hold any one person accountable or blame dealers, I have had systems kick my butt many times as well as about everyone else I know who has worked with them with a lot. Slow leaks can evade even the best of us. The last couple places I have worked have nitrogen compressors and that helps a ton in finding leaks, suck down the system and pressurize the system to a few hundred lbs. and then you can find the leak in most cases that way with soap and water or sometimes depending on what side of the system it can really hiss. This is by far the best and fastest way to find slow leaks that would go undetected by even the best of the best.

Then throw accumulators into the mix like most ac systems have now and then you add a whole new dimension to the mix along with many other pressure sensors and auto mixing valves for heat and cool functions operated by electronic control modules of some sort, just keeps getting more and more complicated just like the rest of the vehicle systems.

[diesel4life]

Having done ac for 20+ years some times ac systems can be a real pain in the but, can't hold any one person accountable or blame dealers

I realize fixes aren't always cut and dry. I'm a very patient person as long as they are making an attempt to make it right, but when a shop cancels on me twice after paying them to do a job I get a little testy. We waited over a week for the first appointment after they replaced the compressor, they canceled on the day of the appointment and did the very same thing the following week. If we were a new customer i wouldnt have much to complain about,but they had already charged good money for less than 2 hours work. Maybe I expect to much but that is my definition of not being accountable.

[Mopar1973Man]

I tend to agree with Bill (Wild & Free) slow leaks and detecting them is a PITA at times. I fought that battle too on my truck where the freon would last just long enough for a summer and be dead. But with some of the knowledge I've learned in the years there is way of improving detection. UV dyes, Freon sniffers, Soap & water, etc. Just have to having the patience to do the work and get it done. Like the Chevy Blazer above has had a slow leak for many years I find got the owner to buy a seal kit and allow me to re-seal it. After leaving it sit on a vacuum all night and seeing the gauge still where I left it last night I was happy to fill it back up in the morning with freon. In A/C work a job well done you shouldn't see the custom again.