pgbeek
Viper Owner
Mine seems warmer although the outdoor temps have been in the high 90's was
wondering if this is a easy check or should I have a dealer do it.
wondering if this is a easy check or should I have a dealer do it.
Has any one recharged their Air Conditioning themselves?
- Thread starter pgbeek
- Start date
You can charge it yourself but I think AC shops or even dealers can do a better job of purging and filling than us using the shade tree approach. I had a dealer purge/charge the system and add dye (for leakage detection) but only after I had changed the O-rings on the compressor side.....they dry out after a few years and are perhaps the leading cause of pressure loss. I figured they'd charge me a fortune for what I could do in 20 minutes with a 10mm wrench and a $1.00 O-ring.
Even the Stealership only charged me $90 for the purge/charge (probably a $40-50 premium over the materials) but I didn't have to buy fittings or gear to purge the system, and they'll refill it gratis within a year if it loses its cold mojo.
Even the Stealership only charged me $90 for the purge/charge (probably a $40-50 premium over the materials) but I didn't have to buy fittings or gear to purge the system, and they'll refill it gratis within a year if it loses its cold mojo.
CSXT802
Enthusiast
It's easy buy the can of R134 the hose that goes with it. On the filter/dryer ( the thing shaped like a coors light can) there is a glass eye on top. If the system is low with the A/C on you will see bubbles move through the sight glass. Add R134 till you see no more bubbles, the sight glass will become milky in color. not hard at all. 
v10enomous
Enthusiast
I had the O rings replaced last year and a good charge and it was all good until I had my car out yesterday. It was still blowing cold but it was 96 degrees and seemed like it was having trouble keeping up. When I drove up to Snakes Alive it was a hot hot day and frost vapor was blowing out of the vent under the passenger airbag. I'm going to get it checked out this week by the shop that charged it last year.
maxdaddy
Enthusiast
Go to auto zone or whatever and get a can of 134, and they also sell a gage to put it in with. when you open your hood it will be on the pass side behind the ft wheel.it will only snap on the right port. run the car and pull the trigger! charge it in the correct makings on the gage and you are done. hope this helps.
malcoll
Enthusiast
Do it right....get a vacuum compressor....vacuum it down and hold the vacuum for about an hour...then recharge with new R134..... you'll love the results. If you don't have the equipment.... take it to the dealership.....
jdeft1
Enthusiast
Buy a 12oz can of 134a. Try to find a setup that has a hose with a pressure gauge. Follow the instructions on the setup you buy but here are a few pointers.
Listen for the A/C compressor. If it cycles on/off/on/off etc, the charge is probably low and you'll see the gauge pressure drop/rise as the compressor turns on/off. If the compressor doesn't run at all you need to bring it to an A/C service shop for repair, evac. and charge.
Purge the charging/gauge hose of air by allowing just a tad of gas to escape as you hook up the fitting to the system service port...You don't want even a tiny amount of atmospheric gas to enter the system. With A/C on, car closed up the gauge should read between 25 and 40psi when properly charged depending on outside air temps. Generally, if you're still getting some cold air, one can is just about right. Go ahead and add the gas. Allow the system to run long enough for it to cool the car down. The compressor may cycle a bit but if the air is cold at the vents, no problem. Also, if you have a thermometer at the vents, the reading should be around 40*(+/-) If you do this when it's hot outside the compressor will likely continue running and the gage will stabilize around 30psi after a while.
These numbers are approximate and depend on the condition of the system and outside air conditions.
Or you could take her to a service shop......
Listen for the A/C compressor. If it cycles on/off/on/off etc, the charge is probably low and you'll see the gauge pressure drop/rise as the compressor turns on/off. If the compressor doesn't run at all you need to bring it to an A/C service shop for repair, evac. and charge.
Purge the charging/gauge hose of air by allowing just a tad of gas to escape as you hook up the fitting to the system service port...You don't want even a tiny amount of atmospheric gas to enter the system. With A/C on, car closed up the gauge should read between 25 and 40psi when properly charged depending on outside air temps. Generally, if you're still getting some cold air, one can is just about right. Go ahead and add the gas. Allow the system to run long enough for it to cool the car down. The compressor may cycle a bit but if the air is cold at the vents, no problem. Also, if you have a thermometer at the vents, the reading should be around 40*(+/-) If you do this when it's hot outside the compressor will likely continue running and the gage will stabilize around 30psi after a while.
These numbers are approximate and depend on the condition of the system and outside air conditions.
Or you could take her to a service shop......
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jdeft1
Enthusiast
blue's right. Overcharging will make it work as bad or worse. Good comment on watching the condensate on the suction line...
TexasPettey
Enthusiast
Easy stuff.
Option1: If you have a Harbor Freight nearby you can get your specialty tools for A/C for under $40: A/C gauges/hoses and O-Ring kit. Walmart has the best prices I've seen on Freon. However, they don't sell the can that has the oil included in the first charge. I'd suggest charging it with a dye kit and then looking for leaks. Vacuum pump can be loaned from Autozone for free. Pump out the old charge once you know where the leaks are. Pop new O-rings on any leaking areas. You may want to do the compressor rings anyway, since you're in there. Vacuum again when you are buttoned up. Add new freon to the low side, with a charge of oil if you are not using the freon can with the first charge of oil in it. Check the gauges to see if you need more freon and add it. Then, tell all your Viper buddies you can fix their A/C in exchange for beer. You'll never be dry.
Option2: Go to Walmart and get a cheap can of freon. Go to Harbor Freight and get the A/C hoses on sale cheap. Add the freon until the gauges on the high and low side read correctl
Option1: If you have a Harbor Freight nearby you can get your specialty tools for A/C for under $40: A/C gauges/hoses and O-Ring kit. Walmart has the best prices I've seen on Freon. However, they don't sell the can that has the oil included in the first charge. I'd suggest charging it with a dye kit and then looking for leaks. Vacuum pump can be loaned from Autozone for free. Pump out the old charge once you know where the leaks are. Pop new O-rings on any leaking areas. You may want to do the compressor rings anyway, since you're in there. Vacuum again when you are buttoned up. Add new freon to the low side, with a charge of oil if you are not using the freon can with the first charge of oil in it. Check the gauges to see if you need more freon and add it. Then, tell all your Viper buddies you can fix their A/C in exchange for beer. You'll never be dry.
Option2: Go to Walmart and get a cheap can of freon. Go to Harbor Freight and get the A/C hoses on sale cheap. Add the freon until the gauges on the high and low side read correctl
Hoosier Daddy
Enthusiast
hooking up a gauge to mine it is in the red danger area, overpressure? Compressor appears to be cycling bringing the guage to barely in the yellow zone. I do get some slighly cooler air out the vents though but not like the past. I have not touched the AC system since buying the car new in 98. But I can tell the AC just isn't the same. Is this a compressor issue?
jwolf
Enthusiast
If you Have "Rural King" they have R134a for $6 a can, our Wal-mart is $9 a can.
TexasPettey
Enthusiast
Which gauge is in the red, high pressure side or low pressure side? Does the compressor turn on and then off? Does the cooling fan kick on corresponding to the compressor kicking on?
klamathpro
Viper Owner
First off, if you never charged it since new, then you are not overcharged. No sense putting a vacuum on it if it's just needs to be topped off. It's also impossible to get air in the system from a leak as long as you have pressure. Check the low side (blue cap) with the car idling with AC on max and full blower. Put your gauge on it and wait about two minutes for it to circulate before taking a reading. It may start in red, but then back down. The gauge results are close but not 100% accurate on the low side.
Common leak spot for all my cars, including the Viper, has always been the valve stem seal on the low side. A trick I have been using for a while on my Lincoln and my Viper is to put an o-ring (with o-ring grease) in the blue cap and screw it on snug without stripping the cap. On the Viper I put an o-ring in the cap and one over the fill shaft just before the beveled flange. This works only on the low side since it's under 50psi. I used a freon leak detector to confirm this actually works and have not recharged in over a year (was recharging every few days before). This saves the trouble of paying $15 for a valve stem and $100 or more to purge and renew the entire system.
Common leak spot for all my cars, including the Viper, has always been the valve stem seal on the low side. A trick I have been using for a while on my Lincoln and my Viper is to put an o-ring (with o-ring grease) in the blue cap and screw it on snug without stripping the cap. On the Viper I put an o-ring in the cap and one over the fill shaft just before the beveled flange. This works only on the low side since it's under 50psi. I used a freon leak detector to confirm this actually works and have not recharged in over a year (was recharging every few days before). This saves the trouble of paying $15 for a valve stem and $100 or more to purge and renew the entire system.
