We have a '98 Dakota Sport with the 5.2L at work, about 190k miles, runs and drives great, but no A/C. System was empty, so I charged it, but the clutch wouldn't engage. Did some troubleshooting, and found that the coil is getting power (if you turn the A/C on, and put a piece of steel next to the clutch, it sticks to the clutch, and stops sticking when you turn off the A/C). However, no amount of tapping or banging on the pulley, or trying to coax the clutch along by pushing it, would get it to move and engage with the pulley.

Any suggestions? Should I try spraying down the clutch with penetrating oil? Bang on it with a big screwdriver and big hammer? It looks a bit rusty, so maybe it's just stuck. If the clutch mechanism itself needs servicing, where can one find parts? So far all I've found at the usual auto parts places is complete remanufactured compressors. Any info is appreciated, we're working in the sun all day and it's pretty miserable inside the truck!

 

Im not sure what you are saying but Im wondering if your clutch plate is missing.

Post some pic's of your compressor especialy the front of it.

I would not go banging on it you may do more damage and no dont spray inside it thats not a good idea.

If it was locked up your pully would not be turning.


This is the clutch cover plate and should be on the front of the compressor

 

This is how it should look

 

Don't use oil on the clutch. If you do it will slip and burn up very quickly.

Engine off, can you turn the clutch plate? The compressor may have seized and burnt up the clutch.

The coil on the clutch may also be bad, even though you get some magnetism out of it. Do you have a way to check the current draw? It should draw between about 2 and 3.9 amps.

It is possible to replace the clutch but you're right, you usually will find just a rebuilt compressor. Nobody takes the time to replace them anymore.

Also, system empty means you need to evacuate it and then check it for leaks. The receiver dryer (accumulator) needs to be replaced as well. Then charged to specs.

 

The Clutch can be replaced but usually a pain in the *** finding the parts because no one does it anymore. I replaced my clutch but to get the parts I had to call a specialty A/C place in Texas and with their help got the correct parts to do it.

You do need some special tools like snap ring pliers and a gear puller not too hard it’s getting the correct clutch replacement parts that’s the problem.

http://www.yellowrosedist.com/


This may help it shows some special tools like a very special puller I just used a regular gear puller and a special spanner I didnt use one just smacked my rachet hard to get it lose http://autorepair.about.com/library/a/1h/bl817h.htm

 

Clutch plate is there, everything looks intact and correct, it spins when turned by hand and you can feel the resistance of the compressor, it just doesn't move inwards to engage the pulley. I was thinking that if I tapped the clutch plate or pushed it, it might engage since it's supposed to be less than 1mm, but I'm wondering if it's rusted to the shaft and unable to move, though there isn't that much rust on it.

I will check the resistance of the coil and the air gap of the clutch first and see what I find, hopefully it is something easily repaired.

As for properly evacuating, testing, and recharging the system, I'd like to, but I'm lucky if I get the money for the cans of R134 I bought. There isn't much budget available for vehicle repairs, especially old vehicles, hence why I'm working on it, rather than bringing it to a mechanic.

Thanks for the info, I'll report back with what I find.

 

Sounds like a weak coil just not strong enough to hold it in check the gap there should be small washers under the clutch plate you could try removing one and see what happens but remember you need that gap or the clutch plate will be rubbing against the pulley and could burn it up you must have the proper gap.

Sounds like what I used to do at work fix it myself or it would never get fixed we had swamp coolers at work and they never paid anyone to maintain them so I did it to keep me and my coworkers cool.

If you do this you can use a simple two prong gear puller attached to the back side just go slow pulling it off and remember get the snap ring out first or you will bend up the pulley. If its rusted on you may bend up the pulley getting it off so I suggest buying a full kit that has a new pulley included my kit was $85 that included the shipping. Sounds like you need your coworkers to pitch in on the cost.

Make sure to get good measurements of everything to get the correct parts from the online store the guy I talked to was very helpful, ask many questions you don’t want to get the wrong parts.

I don’t know how easy it is with your engine to get too the front of the compressor to do this so make sure you can do this at all I have the small 2.5 engine with lots of room to do this. So be sure you have the room inside the engine bay to get at it and fix it before you jump the gun you may need to remove the fan shroud to get at it so think about that.

 

I just took another look at it, and realized that one; I was thinking the whole clutch plate moved against a spring, now I see the plate is fixed, and the clutch disc itself is attached via three thin blade springs and three large pins that ride in rubber sleeves. Secondly, I see that the air gap is huge, it's well over 1mm, and the Sanden service guide that I found (http://www.sanden.com/originals/imag...uide_Rev.2.pdf) specifies .4-.8mm. No wonder it doesn't work, the coil can't pull the clutch disc nearly that far. Looks like I'll determine the exact amount of excess gap, get the plate cover off, and remove the appropriate thickness of shims. Thanks for the info again, I'll check the coil still to make sure it's ok, before I remove shims.

 

Thats a good first try and a simple fix if thats the problem but you may be out of luck you may have no shims to remove.

Dont forget this web helps http://autorepair.about.com/library/a/1h/bl817h.htm

 

Well I don't think we're going to find out now, the tiny little threaded end of the shaft snapped right off as I was tightening the nut, apparently the friction of the nylock nut it had was too great for the end of the shaft, and the threaded end came right off. There was only one .5mm shim on it, so it might not have been enough anyway, but I guess I sure won't have any AC now, unless I happen to find a working used compressor for only a few dollars. Why did Sanden choose such a tiny shaft for this anyway?