Engine Size: 3.2L
Refrigerant Type: R-134a
Ambient Temp: 80
Pressure Low: 32
Pressure High: 155
Country of Origin: United States
After servicing my system for the first time with rebuilt compressor and when the clutch is engages, it was making this light chirp-chirp-chirp sound as if something is not quite centered and is rubbing beneath the pulley hub and a slight tar/plastic smell... I thought maybe something was breaking in around the pulley. However, it didn't make the noise when the A/C was not cycling (clutch disengaged).
Took the car out for a spinand all stayed cool (53-degF) until vent temp decided to rise to 67-deg and the burnt plastic smell was a bit stronger. Turned off the A/C, got it home and lifted the hood to find what looked like splintered melted plastic that had hardened after melted. It was coming out from behind the main pulley on the compressor, which houses the clutch pack. The melted material looked like scotchbrite, that abrasive you clean hard-to-remove things from metal surfaces. But it it black plastic that had hardened... this must have been what was chirping and smelling near the compressor when I was charging it when it was running.
Does anyone know what it may be based on my description? I'm guessing it's the coil that fried? It looked like quite a bit of plastic, but don't remember what plastic components were behind there when I rebuilt it. I was going to go straight to the yard to pull another clutch pack from another compressor but just trying to find opinions of what may have happened since it seemed as if all was rotating good before engagement. Thanks for reading and any help you may offer.
Sounds like the coil was damaged. Need to find out why this happened. Clutch coils fail more from other issues unless it just stops having an electrical function.
The coils can internally short out with age.
If the short isn't enough to trip the fuse, then they get really hot and melt out the resin that's poured around the coil wire.
If they get hot enough they also can melt out the plastic spacers in the sealed shaft bearing and cooking out the grease.
I removed a clutch assembly (shaft plate, pulley and coil pack) from a junk yard. I'll tear mine apart this afternoon, Lord willing, and see what may have caused the rubbing sound and eventual meltdown. Thank you both for your input and I'll post back with what happens. Thank you
Thank you Tim! I removed the original clutch coil /pulley assy and wanted to show what happened... which I have no clue. The very last pic is the one I removed from the yard, but the coil pack doesn't have a diode like original... am I ok with that also? I installed the replacement assembly and the pulley spins very smooth with no chaffing or chirping like my last one did (when the clutch was engaged only. No noise when A/C was off). A funny thing also is that I ohmed the bad coil and it was reading 2.8 ohms and the good one was about 3.7ohms. Thanks for looking and your feedback is appreciated. Sorry for the pics being so big... don't know how to fix it.
NEW COIL PACK
Edited: Sat September 03, 2011 at 11:40 AM by scusack71
Yep, that looks like it internally shorted out
Well, I put the used clutch/coil assembly on and fired it up and clutch won't spin. I checked and found one fuse labeled HEATER, A/C, ATC and it was good. Then I researched my Intrepid forum (I love these forums) and found that one of the radiator fan fuses (2 fuses) is shared with the clutch. The fuse was bad and I replaced and all seemed nice and cool. I'm still going to keep an eye on the newly installed clutch for weird rotation noises like my previous one... Just paranoid I guess.
I also want to say how thankful I am for this forum and the input of all whom dedicate most of there time. I basically had a leaky system and took advice of what to replace and how to flush and what to flush with (thanks HECAT) and the system seems to be working great so far. Well, wish me luck.
Edited: Sat September 03, 2011 at 11:03 AM by scusack71
Well, this coil pack is doing the same thing as the previous. I put it in and the pulley rotated so smooth before putting the belt on. After starting it up and switch the A/C on, it still sounded pretty smooth with no swishing noise. So, keeping it in idle for a while, it sounded great... the car was nice and cool. So I thought this is it....it's fixed.
Then the next day I started it up for a while after mowing the lawn... it was hot out and wanted to cool off. I opened the hood and I really couldn't tell with the engine noise, but thought there may be a possible swishing noise as the pulley rotates over the engaged clutch pack.
I still didn't think of it until yesterday I thought I'd take it for a spin to the bank for the first time since I replaced the clutch assembly. Started to drive with A/C on and started to smell that familiar burning plastic smell. I immediately pulled over shut off A/C and looked under the hood.... I could see small fragments of plastic resin just starting to protrude out the backside of pulley again. Please see pics below. Not as much resin as the previous pics since the drive was so short... but now it looks like I need another clutch assembly. I got a guarantee for a replacement from the junk yard and can pull another one within 30-days... but I just can't comprehend what is causing the burn up.
Is my coil power too high? I tested the coil connector for power with car running in idle and the voltage was 13.65 - 13.79V then when increasing the RPM it seems to max out at 13.9V. Is that too high? Can anyone think of any explanation for the failures? Thanks in advance... again.
Edited: Sat September 03, 2011 at 12:09 PM by scusack71
13.9 volts with no load should be OK. To check for overcharging, start the engine but turn off everything else electric. Rev up to 2000 and measure voltage at the battery. More than 14.5 is a problem.
From the original post..it appears that the clutch burn out occurred on a newly installed reman'd compressor...is this correct? If so, why was the compressor replaced ? What other parts were replaced along with the compressor? How was the system serviced for the compressor replacement? Two clutch burn outs....gut instinct is something is seriously wrong with the system (other that the clutch) or the repair. The clutch failure is simply a result of the problem...not the problem itself. Simply replacing the clutch once more will simply result in a repeat failure....'don't just fix the problem.....repair the cause...'
From the photos it is evident that the compressor is engaging and maintaining contact as designed. The photos indicate a very severe over heating condition as the result of excessive slippage. Looking at the photos I see evidence of excessive cycling and the heat generation of a slipping drive plate. It appears that the problem would be in the increase friction within the compressor which would result in a decrease of compressor rotational speed and the constant drive of the engine (RPM) on the pulley. This could be the result of several factors...too much lube...insufficient lube...incorrect lube or possible refrigerant recharge issues. Another possible cause would be a restricted condenser inlet. This would produce excessive discharge pressures which can result in the same clutch failure issues. The clutch resistance reading posted are will within reason....the voltage to the coil is good. The clutch is not slipping because of a voltage concern. The issue is not the air gap....not evidenced by the photos. Notice the wear is uniform around the clutch drive plate. Another issue could be loss of condenser cooling efficiency due to rad/fan operational issues.
Tell us more about the repair of the vehicle for the compressor install and how the system was serviced. It appears from the post that the compressor is working (the system was cooling) allthough not sufficiently. From the posted pressures it appears that the system was significally undercharged. The high side port is on the compressor body....which would be the highest pressure point in the system. The pressures indicated appear to be less than expected for the ambient temp posted. This possible charge issue may result in a loss of lubricant flow...and thus the increase of internal friction within the compressor.
How much lube was used in this procedure and what type? What flush chemicals were used and how was the system purged to remove possible residual flush chems.
Hey, TRB...the spell check is not working!!!
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thanks for your input 'mk' and 'iceman'.
...forgive me for the book below... but want to give all detail that I can:
I understand that a new clutch isn't going to solve the issue... I guess my point was at the least, I was going to need another one since this one was fried. But my intension wasn't to replace it as the final fix. I know there's something weird going on... but can't figure it out on my own. I'll give you a brief history if it helps:
From the beginning... this car has an engine that I rebuilt including the compressor. It was an engine removed from a car that was running from a junk yard. I rebuilt the compressor using the furum and it included cleaning, o-ring, gasket and shaft seal replacement. The compressor had no issues with it that I was aware of, but I wanted to rebuild all components if possible (alternator, P/S Pump, Compressor, etc).
I originally flushed the system with the HECAT Pulsator and included chemical. I Purged each component with low flow filtered air for about 30-minutes and air bursts to ensure no contaminants and then purge another 30-minutes.
...Well all that went down the drain when I discovered that my evaporator wouldn't hold a vacuum. So just to keep my sanity with the project and cheap insurance... I repaced the evaporator, condenser and both lines connecting to the compressor. So everything is brand new with exception to the lines connecting from condenser to drier and line from drier to TXV (which I did flush during the original flush job I performed). I was very careful when installing the receiver/drier to prevent any air entering the system.
I serviced the compressor with 5oz of PAG46 as recommended by advanceauto.com and also another sheet I found online. The service manual says to use ND8 PAG Oil... but I didn't see such a number on any of the bottles at the store. I used a graduated 1oz syringe with a plastic tube to put into the compressor to avoid extended periods with air.
I have another post with my charging procedure and also some input from TRB. According to the chart in the service manual and the Mastercool Temp/Pressure Chart are conflicting. TRB had a totally different pressure also (see below). I never got a reply if I should have increased 2oz increments of charge as the manual suggests to acquire the pressures. Once you read what I wrote below, maybe you can see if I made any errors. If you would like to read the original post with my charging procedure, it is titled "Correct Pressures? - Nippondesno 10PA15C."
I believe I am charged correctly since I went an ounce in charge more than the service manual but 2oz less than TRB's suggested fill. I was not getting the charges he suggested below. If I need to put the extra 2oz in the system to get to those pressures, I can do that... but I never got an answer if it's wise to add 2oz at a time until I reach the correct pressures posted in the service manual. If you believe I should take a different approach it's all good to me since it's all cheap insurance to me... Any help is appreciated... Thank you.
If the vehicle tag lists 25 ounces I would go with that.
Thanks TRB. Does anyone recommend the service manual instruction of adding 2oz of R-134a at a time until the pressure/temps are acquired from the service manual graph chart? How much more freon above the manufacturers prescribed amount can you go? I serviced this system 1oz above prescribed and my high end pressure on the chart said I pretty within according to my manifold set (getting 155 and minimum on the graph was 170-185psi). The vent temp is cooling at 52-degF, but I have no problem adding but nobody has replied whether that's a good idea or not. If you'de like to see the chart provided (use top margin of graph for 3.2L & not the bottom which is used for 2.7L), I have a link for your reference - See page 24-15, Chrysler LH Service Manual 1998-2001
Just to update my numbers: 32/155 and my condenser outlet temps ranged from 109-121 degF while fans were cycling off and on. I also installed a piece of cardboard on the front of the condenser, as recommended by the manual, to prevent the fans from cycling from high to low.
Iceman: is this something that you suspect that could be causing my clutch pack overheating/meltdown (due to a low charge according to condenser outlet temp and high pressure reading on the service manual chart)? Also, I forgot to mention that the compressor does cycle quite a bit since the only time I was really operating it was while the car was parked, windows open, fan on high. The radiator fans operate very often on this intrepid in while parked, but I did feel the compressor after turning the engine off and it's quite hot. I serviced the 5oz of PAG through the low side. This particular compressor with the 3.2L has the high and low service ports mounted adjascent to each other on the same manifold on the compressor head. My condenser outlet temps ranged from 105-121 degF.
Thank you again.
Edited: Sun September 04, 2011 at 12:59 PM by scusack71
It is assumed that this system is being charged with cans and a manifold...correct? Allowing for the charge of 28 oz (1.75 lbs-Motors Spec/backed with info one other publication), it appears that they system is undercharged. I am not an advocate of charging to a specific pressure...there are simply too many variables that effect this method, it does appear that a serious undercharge exist. An assumption would be that the charge from the cans would be app 33-34 oz (28 + 4 (hose/manifold) + 1/2 for each can (remaining in can after charge). This would require app 3 cans of refrigerant. The most efficient method is to have the system serviced by someone with the correct recharge equipment to insure the correct charge.
The statement that the compressor case was hot....and cycling with the windows open....the clutch burn....my first inclination is a undercharged system and the resultant lack of flow of lubricant. The temp drop on the condenser is acceptable, app 20-25 degrees. High side pressure (discharge) is 155 psi=135 degrees.....condenser outlet temp is 105-121 degrees.
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
No cans... I'm using a 30lb bottle with a weytek digital scale. I've charged the system twice with a recovery in between fills. Both times I'm getting same pressures as listed but I am falling just at the bottom of the window according to the service manual graph. I agree with your disagreement for filling according to pressure but the service manual again mentions this business of adding 2oz at a time until pressures are within range. Unfortunately the manual doesn't specify how many times you can perform the 2oz doses but I assume they believe you are close when charging to spec weight. But I'm not comfortable with that since I'm not sure if it's common practice to do that or how much pressure increase I should expect for a 2oz increase. What you think?
Clutch hub looks like one of those crazy rubberized clutches that harden with age, and have to be gapped at near rubbing to engage. Maximum gap is about 9 mils, but they will still slip, get red hot and burn up the clutch coil. Yours really looks like it got red hot and that is what fried your coil.
Sure sign of these clutches, it take all of your strength to hand close that gap, is or was yours that way? Thought these damned things were history, haven't seen one in a long time. Nippon did make a replacement convention leaf spring clutch, find one of those. Whoever designed this POS should be shot. Been there done that kind of thing.
I have that same car (95 Chry Concorde). My clutch coil has done this before, after replacing the shaft seal - the cause was an unsecured snap ring that allowed the coil to slide out and it melted due to friction after coming into contact with the spinning clutch pulley. Be sure and set that snap ring in so that its all the way in the grove. I used needle nose pliers to squeeze the ends of the snap ring together.
I removed the first clutch/coil assembly and both snap rings were secure. I did install the original shims after I rebuilt the compressor as the manual said was ok if the original clutch was being installed. Also, when I checked the gap, it was snug fit for a business card to fit in... I thought that was rule of thumb. But to get technical, the manual says to get an accurate measurement of the gap is to install a dial indicator to the clutch plate face and energize the clutch and measure the distance it moves in and should be 0.014 to 0.026 in. If not... add or remove shims until it is.
You feel confident it's the clutch gap though? I also believe Iceman's comment of possible undercharging since my pressures were about 20lbs low according to pressures/temp chart in the service manual and may be causing slow circulation of lubricant. I'm not sure where to start but I guess I should probably do the formal check of the clutch gap measurement for sure when I get another clutch assembly. I'm just weary about adding refrigerant to match recommended pressures since I did charge 1oz over Mfr placard weight. Thank you for your input guys.
Edited: Mon September 05, 2011 at 9:30 PM by scusack71
There is a mark on the inside of the pulley and the front edge of the metal part of the coil -- which would confirm Big3's theory. But it could be a chicken and egg situation when the whole thing melts down like that.
A leaking shaft seal will fry a clutch-- is there a chance your shaft seal weeps oil?
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......
Wonder why I even bothered posted to this question.
Clearly don't see any leaf springs on this compressor hub, and Nippondenso was supplying a rubberized clutch, had to stretch that hard rubber so the clutch wouldn't slip, run red hot, and burn things up.
If charge or lubrication is the question, simply suggest hand turning the hub, should be effortless, with no binds. With any, that is a sure sign of the compressor seizing that also causes clutch slippage. From the looks of all the photos, the entire clutch assembly was running red hot. Further indications are the posted odor. Visual signs are smoke.
If the clutch was improperly assembled, that is a problem of an entirely different nature. Not once was clutch gap even mentioned. Talk about getting off on a tangent.
Would have to be dead blind not to see oil pouring out of the compressor seal, that wasn't mentioned either. If the compressor was properly drained, refilled with oil, and with sufficient pressure in the system to overcome the low pressure cutoff system, see no harm in topping it off. But done practically instantly, not a time to play games.
Edited: Tue September 06, 2011 at 10:36 AM by NickD
Nippondenso came out with this rubberized clutch hub back in the mid 80's, replaced it with a leaf spring clutch in the early 90's, surprised it ended up in a 98 Dodge. Unless they got a good deal on some old ones. Check with Tim for a replacement leaf spring clutch. Probably only cost a couple of bucks extra to get a new compressor with it.
Ford was using these damned things back then, everyone sold failed after a couple of years, wouldn't cover it under warranty. Couldn't just replace the hub, the entire clutch has to be replaced. They screwed up, you paid the price.
Clutch gap was too small. A business card is too thin for use to check gap. That damage was due to friction from coming into contact with clutch plate and caused a melt down of the resin that the covers the coil. Must use a dial gauge. I had one from harbor freight that was on a magnetic base. Jumped 12v from battery to engage so proper shim could be installed.
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