A/C cutting out / fan clutch

irboogie · **Posted:** Sun Jul 12, 2009 6:10 pm

It looks like my cool :twisted:

105+ degree south Texas days are causing my A/C to cut out on Hi pressure. I was checking pressures and found all within spec @ 95 degrees with the hood up. It starts dropping out with hood closed and driving. When it starts I can stop and pop the hood and the cooling becomes stable. My electric fan is screaming on high but I feel my fan clutch is not locking up as it should. The coils are clean and looking ok and I have no overheating engine or trans that I can tell, so I guess I'll be spending the $148 on the clutch and going to avoid going out in the daytime...........

DarbyWalters · **Posted:** Sun Jul 12, 2009 6:53 pm

Hey, it is cooler today at 104 ;-)

DOC4444 · **Posted:** Sun Jul 12, 2009 7:34 pm

See if you can find someone else with an '06 who you can compare with before replacing the fan clutch. The '06s are usually OK.

Get 'em both hot. Run parked side by side with hoods open. It will be obvious if yours is putting out a lot less air.

If you do want to go ahead, be sure to check my post on replacement before starting. No reason to cut anything. Not hard with the right approach.

DOC

irboogie · **Posted:** Sun Jul 12, 2009 7:51 pm

I thought about comparing with another, but it blows the same at 80 with the air off as it does at 100 with the air on and the fuse on the electric fan pulled. I will look up your post, it does not seem to bad but it is a Jeep :shock:

Liberty for All · **Posted:** Wed Jul 15, 2009 5:18 pm

It happened suddenly last week on my way across the big valley.
Air started blowing warm instead of cool.
This is the first vehicle I have owned with AC. So how should I proceed to trouble shoot and fix it?
Are there particular AC problems with 2005 gas 3.7L KJ models?
How have other members dealt with this?

Thanks in advance.

:cry:

Joe Romas · **Posted:** Wed Jul 15, 2009 5:52 pm

Liberty for All wrote:

It happened suddenly last week on my way across the big valley.
Air started blowing warm instead of cool.
This is the first vehicle I have owned with AC. So how should I proceed to trouble shoot and fix it?
Are there particular AC problems with 2005 gas 3.7L KJ models?
How have other members dealt with this?

Thanks in advance.

:cry:

You may get more answers in the "general" section. I don't know about failures on kj's yet as my 06 still blows cold. But I spent all last weekend replacing the evaporator on my 00 XJ. They are the biggest AC poblems on XJ's. For a proper repair it should be done by a experienced AC person. Guessing won't work here :cry:

irboogie · **Posted:** Tue Jul 21, 2009 10:33 pm

I got my clutch replaced today, just waiting for a hot day to test it. I did notice you can hold the nut and the housing will spin freely 7-8 times before coming to a stop.

irboogie · **Posted:** Fri Jul 31, 2009 11:16 pm

Well, it is actually a little zipper... I think it is because of the increased air flow over the intercooler. My A/C on the other hand still sucks. I did find the condenser looks clean but after pulling it loose it had a lot of crap in it. So now with a clean condenser , I still have 64 degree air at the vent, 63psi low side and 320psi head. I'm going to try the restrictor tube in the morning. If that does not do it, I'll put a darn Coleman roof top RV unit on it :twisted:

CRDMiller · **Posted:** Sat Aug 01, 2009 1:54 am

Do you have a mesh insert in your grill (aftermarket/custom) or do you use the fia summer front? If so, these have a significant impact on ac performance.

It is also, I suppose, possible that your new fan clutch is just as faulty as your old one. Also, perhaps your electric fan has blown high or low relay or fuse.

It could just be to hot (yeah) or maby you have a faulty thermal sensor somewhere, causing the compressor to cycle less. I don't know jack about ac systems.

Joe Romas · **Posted:** Sat Aug 01, 2009 8:01 am

Check for dead bugs between the radiator and ac condensor. They are very hard to see :lol:

You can't always see them and using a pressure washer will help :lol:

Be aware that you can damadge the fins on the radiator and condensor if your not carefull

Sir Sam · **Posted:** Sat Aug 01, 2009 2:52 pm

Joe Romas wrote:

Check for dead bugs between the radiator and ac condensor. They are very hard to see :lol:

You can't always see them and using a pressure washer will help :lol:

Be aware that you can damadge the fins on the radiator and condensor if your not carefull

Dead bug, gravel, etc, all add up.

I cleaned out the intercooler on my 98 mercedes TD, 215k. After washing it and blowing it out with compressed air I decided to tap the intercooler against the ground.

All sorts of crap started falling out, twigs, rocks, bugs, etc etc. I kept tapping over and over again, more stuff kept coming out.

And this was all crap that couldn't be pressure washed out.

Joe Romas · **Posted:** Sat Aug 01, 2009 6:59 pm

Sir Sam wrote:

Joe Romas wrote:

Check for dead bugs between the radiator and ac condensor. They are very hard to see :lol:

You can't always see them and using a pressure washer will help :lol:

Be aware that you can damadge the fins on the radiator and condensor if your not carefull

Dead bug, gravel, etc, all add up.

I cleaned out the intercooler on my 98 mercedes TD, 215k. After washing it and blowing it out with compressed air I decided to tap the intercooler against the ground.

All sorts of crap started falling out, twigs, rocks, bugs, etc etc. I kept tapping over and over again, more stuff kept coming out.

And this was all crap that couldn't be pressure washed out.

Sam.

Get a bigger pressue washer :lol:

My current pressure washer is 4 gpm, 4000 psi and diesel powered too :shock:

Actually it was a much milder one I had back then :wink:

Joe

irboogie · **Posted:** Sun Aug 02, 2009 2:51 am

I might be onto something, I found that some GM, VW and others have a compressor with a RCV (refrigerant control valve) that when it fails causes a high low side pressure while the high side looks ok..... I'm not wanting to do a compressor but if that will fix it I'll be thrilled. I'm still looking into what compressor the CRD has.

ColoradoCRD · **Joined:** Sun Dec 10, 2006 9:25 am **Posts:** 60

irboogie wrote:

I might be onto something, I found that some GM, VW and others have a compressor with a RCV (refrigerant control valve) that when it fails causes a high low side pressure while the high side looks ok..... I'm not wanting to do a compressor but if that will fix it I'll be thrilled. I'm still looking into what compressor the CRD has.

That is what happened to my 05 last summer: high side was low and low side was high. The AC clutch cycled on and off.

Dealer replaced the A/C system expansion valve inside line between condenser and evaporator, and the AC cycle switch.

My mileage was 38k, and the problem started before I reached 36k, I argued, so it should be covered under warranty. Came out with a good compromise with $361 in charges, I paid $100.

Joe Romas · **Posted:** Sun Aug 02, 2009 8:53 am

CRD's don't have expansion valves per say. We have a "AC orifice tube" in the high side tube going into the evaporator. That line also has a filter in it. If you look at the aluminum section of the high side line (smaller one) just behind the passanger side head light you'll see two dimples about 6 inches apart. This is where it is.

Two weekends ago I removed the dashboard out of my XJ to replace the evaporator coil, heater coil and I replaced the orifice tube also. It's only one tube on a XJ not like hose and tube combination we have on our KJ's so it was inexpensive.

The FSM has a section on diagnosing AC problems.

Liberty for All · **Posted:** Sun Aug 16, 2009 2:53 pm

I finally made time to attempt having the AC that was blowing warm air fixed. The decommissioned Chrysler dealership shop is continuing independent operations and quoted $179. for a check up and recharge.
I phoned around and brought it to one of six local AC garages who advertise as doing this repair.
The shop I brought my Liberty to on Friday called back to say the cause was my compressor coil and that fixing the AC will be $954. so I am not paying that for less than 26K miles on my 2005 3.7L well taken care of Jeep. I paid $154. to pick it up and will continue the attempt next week at completing the fix for a more reasonable fee.
Question, is the compressor at this age with low use really the problem?
and should the old dealer shop's quote for $659. for the same repair be lower than independent shops?
I think something here is not right, but need to make a decision on how to fix the AC with the least damage to my wallet since I am currently unemployed.
Thanks in advance.
Any further insights or advice is requested. :(

irboogie · **Posted:** Sun Aug 16, 2009 7:16 pm

I would check around, some places might be able to just replace the clutch..... If it is a 3.7 the compressor is on top and should be easy, in the diesel service manual says you can service the clutch without removing the hoses but I dont see how...

A/C cutting out / fan clutch

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