2nd Gen Non-Engine/Transmission AC dead... just died

[BK]

Gents/Ladies...



My AC just went up and crapped out. Compressor clutch was engaging and disengaging yesterday ( engage for a second, disengage for about 10 seconds )



Today, the clutch isn't even cycling like yesterday.



nothing but pure hot air coming out of the vents.



It's a 99.



It seemed to be cooling well before this.



I spent the 4th flushing the block and radiator and changing the coolant. . nothing special. As before, when I pulled the lower radiator hose off of the block, it dumped out onto the compressor... but I can't even imagine that that would do a thing.



I didn't put a wrench through the condenser and I didn't beat on any of the AC piping...



Any ideas?



I don't have AC guages, I'll need to call a pal of mine that I think as guages to check the charge.





Thanks

Bob

 

[fest3er]

Originally posted by BK
Gents/Ladies...

My AC just went up and crapped out. Compressor clutch was engaging and disengaging yesterday ( engage for a second, disengage for about 10 seconds )

Today, the clutch isn't even cycling like yesterday.
...

Take the low pressure sensor off the canister by the firewall and clean the contacts and 'shake' it up a little. Likely this is the source of your problem. If the AC comes back, you might consider buying a replacement..... This did the trick for me... .

Fest3er

 

[BK]

fest3er,

thanks , tried that and all the others, checked fuses and relays. . non found to be bad. Vacum is good.

I need to get hold of a set of guages.



urgh... ...



I've been reading some past posts and there seems to be an issue with the evaporator...



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=73604

 

[Matt42]

Sometimes, on some compressors, the little wire that engages the clutch can be disconnected or broken off by brushing against it. I have done that more than once, but not on my Dodge.

 

[JoeBioDiesel]

If the compressor was cycling, then it was getting low on refrigerant. i think you have one of two possible problems.

1) You've got a slow leak that started recently. The A/C was fine, then it started leaking. When it got a little low it started cycling the compressor asnd not it is too low to run it at all.

Look around for obvious oily spots on the A/C system. Pay carefull attention to the lines running to the condenser and to the front of the condenser.

2) Some A/C systems will shut the compressor completely off if it cycles too much. This is done to prevent oil starvation of the compressor. You'll have to fix the low charge problem and clear the Computer codes(this is less likely than problem #1).

Joe

 

[BK]

a friend is bring home a set of gauges to check the charge...

he said 99% of what you said Joe. Thanks...

We didnt know about the code issue. . do we need a reader to clear the codes, or can I do it by pulling the batteries?

 

[JWaters]

ac

Get a test light and see if the compressor is getting fire at the plug, make sure it is also grounded. Antifrezze can make the clutch slip also. maked sure everything is right before you spend money elsewhere. If it is not getting fire there go to the low pressure switch and jump it with a peice of wire. If the compressor comes on your either have a bad switch or low on feron.







hope this helps.



Jeff

 

[BK]

thanks J, did go through all of that... but didnt jump the LPswitch.



I had - read - that you cant jump it since it's a sensor , not a switch and has X resistance value at which it reports low pressure and X+1 resistance value when the pressure is enough... . but don't know this for a fact.



So you've had success jumping the LPswitch?





Relay isn't firing, changed it with the horn relay. . they are the same. . and my horn worked! , but nothing, so I know it's not getting a signal from the control unit. . probably due to the LPswitch... most likey since I had the cycling of the compressor the day before. .

Guages are supposed to be available tonight. . we'll find out what the pulse of the charge is.....



The local shop I trust can squeze me in for a charge this Saturday, if we find tonight that the charge is low .



My 95 Jeep GC just did the very same thing at the beginning of the summer... but figure -AH- I'd rather drive the Ram anyway.....

Than the A/C in the Ram give out... urghhhh.

So I dropped the Jeep off, just got it back , it had very little charge... now it's better than when I 1st bought it a year ago.



So after all the diagnosing from the help on TDR, I'm beating we'll find a low charge tonight. . my biggest worry is that since this happened soo quick... I hope I dont have the famous issue with the evaporator. Since I live on Long Island and spent a whole lot of time camping on the beach with the truck.....

 

[JWaters]

lp switch

It is a on off switch, If the pressure falls to low it breaks contact and stops the fire going to the compressor. You can just stick a small peice of wire in it and by pass it. If you compressor runs check you pressure or replace the switch. It will not hurt anything just dont run it a long time like that or the system may ice up. There is nothing magic about this little switch. Let me know what you find out.



thanks

 

[BK]

J.



yup you were right... . jumping the switch kicked on the compressor.

What I had read some where was incorrect about the resistance.....

my buddy was over with the gauges and I have 20psi ( I think it was 20psi he said, I didnt read the gauges and the engine was running so could have missed the reading... ) But I know he said it was the same on both the high and the low... and the charge was low... and that it needs a charge... .



We looked for small oil trails, couldnt find a thing... but my engine gets washed as much as the body does.....



So next is either travel an hour to his shop or get it charged locally. . I just hate making him wait at his shop. . I can't get out of work earlier and it's a long ride from where I am to his shop in the traffic...



Since there is something in there , I hope that's a hint that the evaporator is fine and not holely... .



After it's charged I'll post if it's back to normal and we'll see if I get more than a couple of weeks out of it... .



Thanks



Bob

 

[BK]

Recharged last night... works great. Lets see how long it lasts.





The buddy of mine that recharged it, is a Volvo mechanic. Just as it's been written hear about the evaporators leaking due to premature oxidation in the Rams... Volvo has had exactly the same problem. Extremely common, here on LI to have an evaporator leak in a few years... . He showed me one they took out recently. . all the dead bugs trapped against the coils, holding the mositure... just eating at the unprotected aluminum evaporator. Cant believe they don't either iradite or anodize the aluminum (sorry ,I bet it's all spelled wrong )... it would protect the evaporator with out sacrificing the thermal conductivity.



Valvo put in a "blow down". . if the air's been on, after the car is turned off, the blower turns on for 10minutes to help dry out the box and evaporator... .



uhm, sounds like project if I ever get the free time.

 

[BK]

After a week, the AC died again... bought the gauge and a couple of cans of 132 and oil... brought it back up. . works fine again. .

Just got back from buying a die UV light... , and it starts raining. . so if it stops tonight, or Saturday. . I'll be on the hunt... .



My bet is on the evaporator... .

other bets... ?



--------------------



edit:

ok, I couldnt wait, went out in the rain... at 1st I was wondering if this light really works, didnt see a trace of yellow anywhere. . then I got into a position where I could see the top of the upper link arm on the passanger side... BRIGHT YELLOW and up above it on the fire wall BRIGHT YELLOW, followed that up to behind the dryer... . now I finally see the hose that drains the box in the cab... BRIGHT YELLOW DRIPS... evaporator UGH... .



I know other folks have had luck with the sealent for the evaporator leaks... . . I was wonder if there is a bad side to the sealent. I don't want to rip the whole dash apart in the hot summer, that's a fall job...



Any comments on the sealer guys/gals???

 

[CstlEng]

I had to pull my dash last summer for the EXACT same thing. The hole started pretty big and just got bigger. A small can of refrigerant would go in and drain so fast the hoses barely changed temp. The sealer did not do the the trick for me. I have a feeling you will be in the same boat.



Believe it or not the worst part was releasing the evaporator from the other tubing: the spring tool I had was too thick to fit into the joint. Thin wall copper tubing split in half lengthwise finally did the trick. Pull the dash by letting the 5 or so hex head screws by the windshield go, then loosen the one or 2 bolts on the kick panels. The dash then pivots on the 2 bolts and can be lifted up and out enough to get just enough clearance to pull the heater box out. I retract my earlier statement: the worst part of the job was figuring out which bolts had to go to drop the heater box. The inside of the box was quite wet in and around the evaporator, and the evaporator was corroded pretty much everywhere. I too live near, in, and on saltwater... good luck.

 

[BK]

CstlEng,



so you didn't pull the steering column and such, just pivoted the dash down. . ???



the fsm has the whole dash assembly and column coming out and sitting on the driveway in peices, before the box come out.





And I think your totaly right, it held a stiff charge for a week, and so far it eat 1 can in 1/2 hour and 2 cans of 134 and 2 cans of oil in 2 hours...

 

[Charliegeis]

evaporator coil

My A/C just quit a couple of weeks ago on my 99 truck. The shop recharged it and added dye. It took it about 2 weeks before it was low on freon again. They couldn't find any external leaks, but using a sniffer at the dash outlets they got high readings which looks like an evaporator problem. Has anyone had any luck with adding sealant?? Looking at the service manual, it looks like a major operation to get to the evaporator coil.

 

[JTeague]

Ill bet its the evap also. Pretty common on the 2nd gen trucks, especially the gassers for some reason. Most of the time when you cant find any obvious leaks in the engine compartment you can pretty much bet on the evap leaking. Sometimes you will also be able to smell refrigerant oil when the A/C is on and this is good sign that the evap has went bad. Also inspect the A/C drain for oil residue. What ever you do DON'T use A/C stop leak. It will stop up the leak and everything else.

 

[CstlEng]

Your are correct, I did have to let the steering column drop down. But, I definitely did not pull it out. Four or six bolts (on the bottom of the column right where it passes into the dash sub frame) let it drop to the seat which gave enough clearance to move the dash around. Some trim needs to be unscrewed in that area and I can't remember if it really needed to come off the column. If it does need to come off, it is only a couple of screws and was very easy to put back together. Both were minor and that was probably why it slipped my mind. Apologies for leaving that out.

 

[BK]

I didnt have your reply this AM. .

I started ripping into it about 9am this morning and a buddy of mine showed up about a 1/2 an hour later. . gave me a big hand. about noon, the only thing left was to get the tool to get the AC line disconnected.

What a mess the evaporator was. . geezz.

Now I need to find the replacement parts and get it back together again.



Considering I don't park under trees, I was pretty amazed at how much compost was sucked up against the evaporator. I ordered one of this air intake filters from genos. I still need to get an evaporator, dryers and grommet for the auto shift linkagea and oh ya the white foam that goes around the evaporator. . I was a mess and some what torn up. tried to clean it and destroyed it.



What a mess. Will I be needing to do this again in another 4 years???? It really pisses me off that I had to dig into the truck this deep for this problem... . It shouldnt have happened.

 

[CstlEng]

At least they should have provided easier access to evap and heater cores. If you have trouble getting that tool for releasing the lines from the evap, you might want to try the homemade one from tubing I told you about earlier, I have used it a couple times since on other things and it worked each time. Glad you got it out. I had all the same compost in mine too... and we don't even have trees here My foam was a little beat up, but was reusable with a little weatherstrip adhesive tape.



Putting it all back was easier than getting it out though. Good luck with it all.



Got mine from NAPA last year for something like $268, and it might have even had some of the thin foam strips on it.

 

[BK]

Ordered the parts from a local dodge/jeep dealer.



The dryer is in ST Louie... . $65

The auto transmission linkage grommet stock. . $3 (each time you pull the linkage, the FSM says replace the grommet)

The evaporator is stock $180



But they couldnt find the white foam surround.....

There's no part number for it and it's not shown in the mechanical break out. He remembers it... but it's been a while since he looked one up for the Ram. And he thought it was on the diagram and parts list.



So the stock guy went and pulled the evaporator from stock, non

in the box either. BTW the parts guy described the evaporator, and he said it now has "fine presreen" in front of the coils.

So in trying to find out what's up with the white foam surround, he went out to the shop and asked one of the techs...

I thought the white foam was a bad idea it seems it would hold water around the bottom of the coil... since it isnt pourous (sp?) the coil will always be in a small puddle. The tech said that part of the fix is to get rid of the white foam surround, and that the evaporator was redesigned, hence the prescreen.



The white foam was bent up around the bottom of the evaporator and forms a tub that traped the water and compost at the bottom of the coil.



Anyway, gotta run out and pickup what they have, my dryer should be in either Friday or Monday. Once I have the evaporator, I can start putting things together.



For those wanting to tackle the job, if you have all the parts in front of you, you can get it all apart and back together in one long day with some help. . or one -take your time- whole weekend.

Besides the home made AC line disconnect tool described above, there is one that looks like a sissor with handles on both ends, a plastic tool. It's about 6 bucks, it's thin enough to fit between the fire wall and the connectors to disengage the locking loop and get the lines apart. The round collars are too thick, again as mentioned above by another member, thanks for the hint. Because of that, I bought the chinzy looking tool that was thin and it worked great. The collars just wouldnt fit.