Since warm weather is just around the corner I need to get my A/C fixed. I filled it with new coolant and it lasted good for a month, but it eventually leaked out. I used the leak test stuff that you put into the AC lines and you use the glasses and the light to check for leaks however did not find the leak. Where are the most common places to check for leaks or even replace? I thought about buying a new seal kit but wanted to get some opinions first. Thanks all. 

The worst place is the evaporator. Can't check it without removing the dash and hvac box. When I opened mine up there was a green slimey mess in the botton of it from the dye I put in. The other bad place is the compressor seal, can't really see it either. I kind of gave up on the dye since you can get to all the other connections with soap and water. 

A new compressor is not but about $125 on rock auto. Last year anyway, not sure if the new tarriffs has run that up.

Pretty much exactly what dripley said...more than likely the evaporator being that you can see everything else.  Leaks are almost always  at a connection point or pinholes in a corroded core.

 

Mine does the exact same thing...I get a month out of a charge and no visible leaks.  Soon I'll be making my own custom dashboard and console...everything dash related will be removed.  I will address it then.  Meanwhile I'm on a $3.99/month freon budget. 

5 hours ago, dripley said:

The worst place is the evaporator. Can't check it without removing the dash and hvac box. When I opened mine up there was a green slimey mess in the botton of it from the dye I put in. The other bad place is the compressor seal, can't really see it either. I kind of gave up on the dye since you can get to all the other connections with soap and water. 

A new compressor is not but about $125 on rock auto. Last year anyway, not sure if the new tarriffs has run that up.

Thanks! I hate throwing parts at unknown problems but when it comes to AC sounds like that might be my best bet. I might start with the new compressor, since it is the lesser of the two evils or so it sounds. 

1 hour ago, Bullet said:

Pretty much exactly what dripley said...more than likely the evaporator being that you can see everything else.  Leaks are almost always  at a connection point or pinholes in a corroded core.

 

Mine does the exact same thing...I get a month out of a charge and no visible leaks.  Soon I'll be making my own custom dashboard and console...everything dash related will be removed.  I will address it then.  Meanwhile I'm on a $3.99/month freon budget. 

Thanks bullet, I have not messed with anything AC honestly so I’m gonna look up the evaporator, see if I can find a few pictures of someone diving into this repair previously since it sounds pretty involved. 

Yeah ripping the dash out is a laborious job but nothing that a lot of time won't help.  I would look there first if no leaks are visible under the hood.  Your compressor sounds like it's OK...just got a leak somewhere. 

Itmis not as bad as you think. I did mine several years back using @Mopar1973Man article. Replaced the the dash and rebuilt the HVAC box too. I spent 3 days as I remeber. But it could be done 1.5 or 2 days easy. I took a lot of breaks. Plus I dont get in a big hurry either when in unfamiliar territory.

Thanks @dripley and @Bullet I am going to tackle this for sure, I have a Tahoe that I can drive while my truck is down. Gonna look up the moparman article for the dash. I appreciate the help. What else should be replaced while I’m in there? Or is their a kit for rebuilding it? 

I read you added coolant, and talking about A/C stuff?? 

If anything is wrong with the core, just replace it, their stupid cheap. Also replace your drier at the same time. Do like the others said use soapy water all over lines and check for any leaks. It may be time to pull the dash... the m73m article nails it down, I also have my own thread of complete removing everything inside the interior of that helps you.. 

4 minutes ago, Stanley said:

I read you added coolant, and talking about A/C stuff?? 

If anything is wrong with the core, just replace it, their stupid cheap. Also replace your drier at the same time. Do like the others said use soapy water all over lines and check for any leaks. It may be time to pull the dash... the m73m article nails it down, I also have my own thread of complete removing everything inside the interior of that helps you.. 

Sorry, r134a is what was added. Not engine coolant. I saw on rock auto they aren’t expensive at all, roughly $40, for evaporator core and heater core. I would rather throw new parts at the hvac box while it’s out, but will do some more reading and found the moparman article on the hvac box removal. 

Some places that are tough to detect leaks. 

 

Compressor front seal. 

Evaporator leaks. 

 

These two places are tough being if you use UV dye in the system you'll never see signs of it being slung from the pulley or inside the HVAC case because of where it's at. The dash doesn't get removed per se but just swung on the passenger side just enough to slide the entire HVAC unit out of the dash. It just all but time. 

I would get a hold of an electronic a.c leak sniffer before pulling and changing parts, they should be able to pick up a leak at the compressor or evaporator.  A good quality one like Robinair or such maybe what’s needed 

23 minutes ago, Mopar1973Man said:

Some places that are tough to detect leaks. 

 

Compressor front seal. 

Evaporator leaks. 

 

These two places are tough being if you use UV dye in the system you'll never see signs of it being slung from the pulley or inside the HVAC case because of where it's at. The dash doesn't get removed per se but just swung on the passenger side just enough to slide the entire HVAC unit out of the dash. It just all but time. 

I was just looking over your article where you discuss this and have a strap from the passenger side grab bar. I feel comfortable enough taking it apart, but will take a few days to do it for sure. 

17 minutes ago, 01cummins4ever said:

I would get a hold of an electronic a.c leak sniffer before pulling and changing parts, they should be able to pick up a leak at the compressor or evaporator.  A good quality one like Robinair or such maybe what’s needed 

That’s a great suggestion to possibly save myself some time, I might check with oreilly, see if they have one for rent. 

If your system is empty so you don't need to pay to evacuate, see this.

 

I haven't tried it but you may get lucky.

 

 

Thanks @Junkman I am going to try the leak detector first. See if I can pinpoint where the leak is coming from. That guy is passionate about that ac stop leak for sure. 

So, its been a minute since I have messed with my AC, but I have purchased an evaporator and a heater core. I am looking to tackle this repair soon, before the heat sets in...I didn't drive my truck much last summer due to the AC issue. I never could find the leak even with the sniffer, so my thoughts are that it is likely the AC evaporator core. I did get a few hits with the sniffer inside the cab, close to the HVAC box, but no hits anywhere under hood. While I have the HVAC box pulled, are there any wear items I should consider putting in while its apart? Thanks.

Another spot the sniffer will miss is the compressor front seal. 

29 minutes ago, Mopar1973Man said:

Another spot the sniffer will miss is the compressor front seal. 

That will be my next part to replace if the evaporator does not fix the issue. The evaporator was the cheaper of the two evils, but would likely be harder to replace..However, I did get a few hits inside the cab with the sniffer, so that's why I decided to start there. I do hear a clunk at times when the heat is turned on. What would cause that to happen?

Edited March 12, 20205 yr by Red Rambler

@Red Rambler, since you are going to the trouble of replacing the evaporator core and heater core, I highly recommend adding a cabin filter.  Geno's Garage sells an excellent after-market one for abut $50.00  See photos.

 

My AC system started losing refrigerant on a regular basis around 250,000 miles on the truck.  I elected to replace the original compressor at 270,000 miles with another Denso unit just because of the wear factor.  No more losing refrigerant after the replacement. 

 

At 283, 000 miles, I removed the HVAC unit and replaced the heater core with one from Geno's Garage.  I elected to not replace the evaporator core because it appeared to be in excellent condition externally.  Some people will think I am nuts for not doing this, but the AC is still working fine over 50,000 miles later.

 

While I had the HVAC unit out, I did get some different sizes of glue-on weather stipping from the local hardware store to reseal around the ventilation doors.

 

You didn't say how many miles are on your AC compressor.  I don't think you can go wrong by replacing the either the compressor or the evaporator core first since both are likely candidates for failure.

 

- John

 

 

While you have it apart the accumulator should be replaced along with the orifice tube and all the 0-rings.  The O-rings should be coated with AC mineral oil and not PAG oil before installation.   You will need to add 2 ounces of PAG 100 oil to the system for the replaced evaporator and 2 more if you replace the accumulator. 

 

You may want to replace the fan motor; it's old and tired and dido for the heater/AC blend door coupler.  

 

https://heatertreater.net/dodge-ram-95-02 

 

 

5 minutes ago, Tractorman said:

@Red Rambler, since you are going to the trouble of replacing the evaporator core and heater core, I highly recommend adding a cabin filter.  Geno's Garage sells an excellent after-market one for abut $50.00  See photos.

 

My AC system started losing refrigerant on a regular basis around 250,000 miles on the truck.  I elected to replace the original compressor at 270,000 miles with another Denso unit just because of the wear factor.  No more losing refrigerant after the replacement. 

 

At 283, 000 miles, I removed the HVAC unit and replaced the heater core with one from Geno's Garage.  I elected to not replace the evaporator core because it appeared to be in excellent condition externally.  Some people will think I am nuts for not doing this, but the AC is still working fine over 50,000 miles later.

 

While I had the HVAC unit out, I did get some different sizes of glue-on weather stipping from the local hardware store to reseal around the ventilation doors.

 

You didn't say how many miles are on your AC compressor.  I don't think you can go wrong by replacing the either the compressor or the evaporator core first since both are likely candidates for failure.

 

- John

 

 

 

Thanks Tractorman, I will take a look at the cabin filters. I can only assume my compressor is original with 140K on it. At this point I am jus throwing parts at it.

5 minutes ago, IBMobile said:

While you have it apart the accumulator should be replaced along with the orifice tube and all the 0-rings.  The O-rings should be coated with AC mineral oil and not PAG oil before installation.   You will need to add 2 ounces of PAG 100 oil to the system for the replaced evaporator and 2 more if you replace the accumulator. 

 

You may want to replace the fan motor; it's old and tired and dido for the heater/AC blend door coupler.  

 

https://heatertreater.net/dodge-ram-95-02 

 

 

 

I have these added to my rockauto cart, Blower motor resistor: 20.79, Blower motor 39.79, and a A/C accumulator/dryer kit: O rings, accumulator,  and condenser to Evaporator Line: 34.79.

I will take a look at the Heater treater part, as I might as well if I am inside the HVAC box.

Thus far I have purchased: Blower motor, accumulator kit, O-rings, condenser to evaporator line, orifice tube, a bottle of PAG 100, Evaporator and heater core. I still need to find the AC mineral oil. I plan on taking a few days to complete this but will take some pictures for reference upon reinstall. Thanks for the help with this so far, I know I will likely have more questions. I will be ordering the heater treater part as well for the blend door. This is quite pricy, so fingers crossed it is the evaporator and not the compressor lol!!

Edited March 13, 20205 yr by Red Rambler