AC Problems

[49erRider]

Well after a lot of troubleshooting with my AC theres one more thing i want to try.

I had a leak replaced the evaporator, the good news is the 134a is holding at a good level so I think I took care of that. Bad news is the air gets warm after about 10-15 minutes and won't cool down until the Jeep cools down.

Heres my thought, I read a lot of threads about there being to many shims so I thought I would remove one. I just want to make sure I"m going about this the right way.

I take the center nut off, which I need to find some way of keeping that plate from spinning, any suggestions? Then once that nut is off I should just be able to pull that bolt out right, then just remove a shim?

Also I broke the radiator fan shroud in the process, anyone have an extra or know how to get that thing out without breaking it?

Thanks a lot guys!

Brad

 

[garth93xj]

is your axillary fan kicking on when you turn on your ac?

what are your pressure readings (hi and lo) with your ac running?

sounds to me like you have a clogged line, probably around the expansion valve or orifice tube depending on year, where the liquid is pushed through and becomes cold before it enters the evaporator and boils.

the easiest way to tell is if you hook up the gauges and both hi and lo are reading the same pressure you have a clogged orifice tube. There should be a large difference in pressure, mine right now on a 70 degree day will be running 32 psi low and 132psi hi.

I have never heard of the shim idea, but I do know that most of the time if you take that clutch assembly apart you will never get it back right

 

[garth93xj]

p.s. forgot the easiest fix of all....check your freon level, low levels will allow it to cool until the engine gets too warm and there is not enough freon to keep the fluid cold before it reaches your evaporator

 

[UNCC_99XJ]

is your axillary fan kicking on when you turn on your ac?

what are your pressure readings (hi and lo) with your ac running?

sounds to me like you have a clogged line, probably around the expansion valve or orifice tube depending on year, where the liquid is pushed through and becomes cold before it enters the evaporator and boils.

the easiest way to tell is if you hook up the gauges and both hi and lo are reading the same pressure you have a clogged orifice tube. There should be a large difference in pressure, mine right now on a 70 degree day will be running 32 psi low and 132psi hi.

I have never heard of the shim idea, but I do know that most of the time if you take that clutch assembly apart you will never get it back right

Aux fan does not kick on, as it's not designed to on the 2000 and 2001 models. Last summer when I started helping him with his A/C I was baffled by this as well.

I believe pressures should be equal on both sides when the gauges are hooked up...time to dig the FSM back out and do some homework....haven't done much A/C work since last summer.

Brad, if you're free Sunday, we'll hook my gauges back up to it again and see where your levels are. I don't trust the gauges that you get with the recharge kits very much...i've found the majority to be inaccurate. I'd hold off on tearing the clutch apart...i've never heard of that issue that we talked about on the phone last night (not saying it doesn't exist, I just think it's highly unlikely...but I could be wrong). I still think we don't have the level quite right.

 

[garth93xj]

Aux fan does not kick on, as it's not designed to on the 2000 and 2001 models. Last summer when I started helping him with his A/C I was baffled by this as well.

I believe pressures should be equal on both sides when the gauges are hooked up...time to dig the FSM back out and do some homework....haven't done much A/C work since last summer.

Brad, if you're free Sunday, we'll hook my gauges back up to it again and see where your levels are. I don't trust the gauges that you get with the recharge kits very much...i've found the majority to be inaccurate. I'd hold off on tearing the clutch apart...i've never heard of that issue that we talked about on the phone last night (not saying it doesn't exist, I just think it's highly unlikely...but I could be wrong). I still think we don't have the level quite right.

with the engine running and the ac on high there should be a large difference in hi and lo side (not to be a smarta$$ but thats why they call them low and high side)

and the reason why mine is running 32-132 is because it is a r-12 system, with yours being a 134 system it has the different pressure level than mine so if yours was running 32 on the low it should run around 200 high side give or take some due to wearing of the compressor.

this is from ASE book I have and is just a general rule of thumb "ambient temperature X 2 + 50= good high pressure reading low should be between 30-40 for good reading may vary depending on ambient temperature"

if your reading equal pressures hi and lo with the system off, that is only your static pressure reading which is good mainly for letting the tech know that the system has enough pressure to begin leak testing and check to see if a coolent bottle has been contaiminated.

I am an ASE certified tech, and used to work all summer on just ac systems of coarse I had it easy with the do it all machine lol

 

[garth93xj]

just found this on alldata

2000>jeep>cherokee>6cyl>air-conditioning>fan

When the air-conditioning is used the engine ECU grounds the A/C relay coil allowing current to flow through it. This activates the A/C relay which then supplies current to the A/C clutch, fan diode assembly and cooling fan relay. The cooling fan relay is activated and the fan operates. When ever the air-conditioning is used, regardless of engine coolant temperature, the auxiliary electric cooling fan operates

hope this helps

 

[UNCC_99XJ]

just found this on alldata

2000>jeep>cherokee>6cyl>air-conditioning>fan

When the air-conditioning is used the engine ECU grounds the A/C relay coil allowing current to flow through it. This activates the A/C relay which then supplies current to the A/C clutch, fan diode assembly and cooling fan relay. The cooling fan relay is activated and the fan operates. When ever the air-conditioning is used, regardless of engine coolant temperature, the auxiliary electric cooling fan operates

hope this helps

I spent many hours searching last summer on here and many others with 00 and 01's also say their aux fans do not run with the a/c on. His fan still works though, as it comes on when the engine temp gets too warm.

I'm going to dig through my FSM tonight if I get a chance and do some reading. Been needing to brush up anyways now that A/C season is here. I have recharged A/C's (the proper way) several times and have a good idea of where pressures should be.

Not doubting you though.

 

[garth93xj]

if you need any help just let me know

 

[49erRider]

Hmm I'm just not sure. Today on the way home (interstate it stayed cold for about 25 minutes)

The threads I've read on the spacing issues seem to fit the bill perfect.