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Mopar1973Man

A/C Evaporator & Heater core write up!

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Well gang... I just got the A/C Evaporator and the release tool for the A/C lines. I got the vacuum pump and freon maniold/gauges coimng too. I'm spending some good money so I become a a/C recharge center here in the valley since no one does here. But on with my project as soon as the rest of my tools get here I'll be on the road to starting the project.

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You need a digital scale and a vacuum pump is an absolute 100 % must have if you are going to do AC work. Also invest in an AC O-ring kit and a sniffer also comes in very handy.

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I charged up the A/C system on my truck about 2 weeks ago. I have an electric and pneumatic vaccum pump to evacuate the system but when I put my gauges on the system, the low side pressure was still 16 psi, so I just added a can of R134a and it is good for another season. The leak is so slow that it take over a year or the freon to all leak out. Not enough to lead a dye trail or for a sniffer to pickup. What I want to know and perhaps this is material for a separate thread to start.......is there a way to access that evaporator pan inside the dash to clean it out and ensure the condensation drain is open and all is nice and clean. GAWD!!!!! I HATE the prospect of removing the entire dash to get in there. Anyone have any suggestions, tips, or techiques??? :banghead:

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Well I got started on the A/C...

I started by pulling all the ngine side stuff out of the way... BHAF, tubing, heat shield... No comment about my silencer ring... (Shhh!)

http://forum.mopar1973man.com/attachment.php?attachmentid=1039

Drain some coolant off and pull the hoses loose to the heater.

http://forum.mopar1973man.com/attachment.php?attachmentid=1038

Broke out with the special release tool and pulled the A/C lines loose...

http://forum.mopar1973man.com/attachment.php?attachmentid=1037

Opps... I though I had gotten all the pressure off... Not much left but enough to scatter the dye pack around the firewall. Yes I'm using a black light ot show this.

http://forum.mopar1973man.com/attachment.php?attachmentid=1036

Pull the first screws of the kick plate and remove the kick panel. Then remove both bolts on each side. The 5 screws across the top, and there is 2 bolts and 2 nuts in the center. 5 speed you got to pull up the console. Also drop the steering column down on the seat which is 2 10mm nuts.

http://forum.mopar1973man.com/attachment.php?attachmentid=1035

This is where I quit for the moment... Whew!

http://forum.mopar1973man.com/attachment.php?attachmentid=1034

WARNING! The dash does have sharp edges and will cut you easy... Becareful!

http://forum.mopar1973man.com/attachment.php?attachmentid=1040

Then... When it rain it pours... :cry: My heater core is going south...

http://forum.mopar1973man.com/attachment.php?attachmentid=1041

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Then... When it rain it pours... :cry: My heater core is going south...

if that's what an 02 core looks like....i'm afraid to see what my 99's looks like thanks for taking the time to document your work

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Well when it rains it pours big time in Idaho... There isn't a heater in the western states according to Napa. The closest one is in New York state... Then I ask my sales rep to dig and find out if there is another vendor that can handle it. Sure enough he called the dealer and I was quoted $280 bucks for heater core from the Dodge $tealer... :stuned: Well I told him to hang on to his notes and I'm going to do some research... So I call one of my vendors and check to see what he's got... well so far it looks like a waiting game and see who can get a heater core the quickest and cheapest... Hmmm... Now I'm stuck driving a gasser... :rolleyes: I was just getting all excited because the weather was warming up and I was starting to pull good MPG in the Cummins and hit another rock wall... :banghead: (Ouch ouch ouch!)

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Then... When it rain it pours... :cry: My heater core is going south... http://forum.mopar1973man.com/attachment.php?attachmentid=1041

That's why I always recommend budgeting in a core replacement at the same time as the evap swap........it adds $100 or more to the job, but it's almost a lock that the core's going to fail. If you didn't replace it now, you'd be doing the job all over again, probably in winter weather! I'm surprised you didn't smell any antifreeze in the cab.

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I did once in awhile but excused its as fluke because it like once a year I might smell it... When I pulled it out it should explain the smell. But it sucks that now I having to wait for a heater core to be shipped from Canada... Come on UPS... Looking for a Brown truck to show up...:cheerleader:

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Well after a long wait... I finally got a heater core and got it back together. Come to find out doing a A/C evaporator and heater core are simple jobs to do really... I think the forum hyper and rumors make it sound horrid to do... Really it's not bad... Time consuming but not bad. First thing to pull the battery cables. The big thing is getting the engine bay side first get everything out of your way. http://forum.mopar1973man.com/attachment.php?attachmentid=1039 Evacuate the A/C system and drain your coolant down some for the heater hose. Pull the hoses loose on both the A/C and the heater core. There is 4 nuts holding the HVAC box on the engine side. http://forum.mopar1973man.com/attachment.php?attachmentid=1037 One is hidden under the PCM. Make sure to use duct tape or simular to cover the pipe ends from getting dirt in anything. Now the dash is easy... 2 bolts under each kick panel just loosen them and leave in the body. If you got a manual like me you got to pull up the console. Under the console is 2 nuts and 2 bolts. Now pull your knee bolster and take the 2 nuts out holding the sterring column. Let the steering column rest on the driver seat. Take the 5 screw across the dash top out. http://forum.mopar1973man.com/attachment.php?attachmentid=1035 At this point have a tie strap handy. Take the passenger side and lift up slightly and slide outwards off the bolt. Don't get overly carriered away be careful with all the plastic. Tie the dash up using the strap. At this point you got a few more nuts. There is 3 nuts to pull here. Rught next to the in/out vent door there is a nut hidden in the corner. Then there is 2 nuts stacked on the stud near the heater core. The ground strap in hooked to it.. Now back to the driver side and look for the vacuum connection. It will be rapped in foam it should be near the drivers side floor vent. The electrical on the passenger side needs to be pulled loose too. http://forum.mopar1973man.com/attachment.php?attachmentid=1034 now the HVAC box is ready to come out. Carefully wiggle the box around and it should pop out off the firewall. Guide it to the passenger side floor and slide it out under the dash. You'll need to lift it slightly being careful of the the dash and HVAC box. Don't force anything... If it not coming out double check yourself again... Whew! HVAC is out of the dash now. http://forum.mopar1973man.com/attachment.php?attachmentid=1090 Now the heater core is held in by 3 screw and it can be removed by pulling straight up. Nothing hard or difficult. http://forum.mopar1973man.com/attachment.php?attachmentid=1088 As for the A/C evaporator that requires the case to be split open. There is a mess load of phillip screws running the edge of the box. Now there is 1 screw hidden under a floor vent cover carefully pry the cover off to access it. http://forum.mopar1973man.com/attachment.php?attachmentid=1086 http://forum.mopar1973man.com/attachment.php?attachmentid=1087 Flip the case back over to the other side (screw holes pointing down). Now carefully pry the HVAC case open and lift the top off everything. A/C Evaporator case be lifted out and replaced at this point. But I highly suggest blow out with compressed air the ducts and fan. Your going to need a roll of weather stripping foam to reseal the A/C evaporator and heater core. http://forum.mopar1973man.com/attachment.php?attachmentid=1093 http://forum.mopar1973man.com/attachment.php?attachmentid=1092 Somethings to be careful of during re-assembly. Make sure your careful of the vent doors in side the HVAC case. There is a spring loaded door that you must be careful to not crush or damage. Then the blend door you got to line up the pivot post. Now re-install the HVAC case back in the dash the reverse order you took it out. As for recharging the system... :cool: What you need... http://forum.mopar1973man.com/attachment.php?attachmentid=1057 Should look like this hooked up... http://forum.mopar1973man.com/attachment.php?attachmentid=1096 Drawing down a vacuum. http://forum.mopar1973man.com/attachment.php?attachmentid=1097 Then shut your manifold and shut down the vacuum pump. Just for protection I got a can of PAG oil charge for the system. Once you got the can hooked up and punctured I bleed the yellow hooks at the manifold just crak it open and purge the air out. With the vacuum present I opened the low side valve and allow the oil charge to be drawn in. Closed it and switched cean to freon and bleed again. I allowed the first can to be pushed into the system. Now I started the engine. I continued to add freon one can at a time. I also used a bucket of hot water from the tap to help push the freon into the system. But I added 4 cans of freon on got to this point as seen on the gauges. now I got ot remember my current outside temps are about 55*F so the freon will expand more as the days warm up. http://forum.mopar1973man.com/attachment.php?attachmentid=1099 http://forum.mopar1973man.com/attachment.php?attachmentid=1094 Nice part is... http://forum.mopar1973man.com/attachment.php?attachmentid=1095

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I think i will send you a plane ticket to help do mine.

and it still might be cheaper than paying one of the local shops. last summer, i charged my ranger. well the auto parts store's diy can job made my schrader valve leak. i knew for certain that was the problem(as i could hear and physically see it leaking and it did not before i started). took it to the local shop. where i explained what happened and what i wanted. when i came back to pick it up, they vacuumed it, but some kinda dye to check for leaks, just like i told them...only the schrader valve(now i got that crap on the underside of my hood), change the valve and refill. at...wait for it...wait for it $400+tax! why don't the part shops stock that stuff. the one they sold me was the exact same as a tire stem valve!(too small for my ranger)

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I think i will send you a plane ticket to help do mine.

Dont ask me what we did, all I know is we vac. the system and put what it called for and presto. When it blew it took out everything, comp, valvue, evap. Right at 800.00 in parts a labor.

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I need to recharge my a/c also and need to see a picture of exactly where you hook up the recharge kit. This is my first time doing this. Does it take very long to do it?

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It's the port right behind the passenger headlight that comes up and is almost flush with the top crossover beam. It has a big black cap and you can't miss it. It hardly takes any time at all. Maybe 2 minutes to get it back to regular pressure from having no pressure at all. Your A/C compressor MUST be on while you are filling it, if it is not on, it is detection too low of pressure so there is a connector going to the top of the accumulator (air tank looking thing) that you jumper the 2 contacts on to get the compressor to engage.

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I need to recharge my a/c also and need to see a picture of exactly where you hook up the recharge kit. This is my first time doing this. Does it take very long to do it?

http://forum.mopar1973man.com/attachment.php?attachmentid=1096

Blue hose (low side)

Read Hose (high side)

Yellow hose vacuum or freon change.

Charge with freon till the low side is about 40 PSI...

Posted Image

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I need to recharge my a/c also and need to see a picture of exactly where you hook up the recharge kit. This is my first time doing this. Does it take very long to do it?

On my ruck, the low pressure side port is right in between the air filter box and turbo in close proximity to the air box. The high pressure side port is behind the passenger side head light like ISX described. You can buy one of the recharge kits at Wally World that comes with a charge hose and gauge. I did it this way this year since I had a leak and charge the system with a kit that had oil, R134A, and stop leak. Attach the charge hose to the can. Then attach the charge hose to the LOW PRESSURE port back by the air box. Now back the charge hose connector off a half turn or so until you can hear and feel a good stream of R134A escaping. This is to purge the charge hose. Once you hear and feel the R134A escaping from around the threads, retighten. NOTE: If there is NO freon pressure in your A/C system when you attempt to recharge it with freon (R134A), you will need to evacuate the A/C system with a vaccum pump. Otherwise you may have moisture in the system that can freeze up and cause problems. Now start the engine up and turn the A/C on and up to max and fan to max. Allow the A/C system to operate a minute or so to reach equilibrim and then press the button/valve on top of the freon can to allow the freon to be drawn into the A/C system. NOTE: If you hold the can right side up, it take forever for the freon to be drawn into the A/C system. I turn the can up side down so the freon will go in faster as liquid. Some folk may or may not agree with method . Use the method you feel comfortable with. Observe the gauge on the charge hose. In the heat of the day for most areas, the low side pressure should read around 45 psi but refer to the chart in the shop manual for the proper ambient temp. and low side pressure combination. Once you have reached an acceptable low side pressure or the can is empty, release the button/valve and remove the charge hose from the low side port. You're done! This is the poorman's/cheap guy's method. The proper method is to use a proper set of gauges, like Mike did, hooking up to both low and high pressure side ports. Use a thermometer in the A/C output vent to verify correct temp. If no or little freon pressure is present when checking for proper operation, use a vaccum pump to evacuate and dry out the system. I like to hold a vaccum for about an hour to ensure any condensed water and vapor is removed. With the prices dealers and shops charge to service A/C systems, you can buy all of the equipment and freon much cheaper and do it yourself. Anyhow, I gues I made it clear as mud and left you even more confused now? :lmao: (I'm good for that) Mike's write-up is EXCELLENT with some great pics that help guide you. Follow his directions and you should be fine.
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The red hose is really the high side? Even the haynes manual says its the low, and I remember the guy filling it up using the red hosed port, only. I need gauge proof now :lol:

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The red hose is really the high side? Even the haynes manual says its the low, and I remember the guy filling it up using the red hosed port, only. I need gauge proof now :lol:

Ok let trade it up... Now here is gasoline Dodge V8... Look where the blue and red hoses are now... http://forum.mopar1973man.com/attachment.php?attachmentid=1058 Now diesel... http://forum.mopar1973man.com/attachment.php?attachmentid=1096

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Well that doesn't really help me. The haynes manual specifically says put it on the one behind the headlight, and I recall them topping it off with the same port. You say this is the high side port though so now I'm beginning to wonder.

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I read a snipit from a thread here about adding freon with stop leak in it..........................VERY VERY VERY BAD IDEA. Would you pour in stop leak into your crankcase to stop an engine oil leak??????????? No, you just created a more expensive repair rather than finding the leak and fixing it. You will most likely trash the compressor and or plug the orifice tube along with the condensor and evaporator, some of the sealers added can be caustic to aluminum also.

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