R32 Gt-r In-situ Airconditioner Windings Removal

[lwells]

Many R32s owners have reported problems with the airconditioning system. A number have noted that it continually blows fuses (particularly fuse #10), a sign that the windings of the electromagnetic clutch -- used to engage the compressor -- may have worn and are thus drawing excessive current.

The simple solution is to remove the compressor and take it to an electrical engineer. However this requires decompressing/draining the aircon system (and thus re-gassing once the compressor is reinstalled) and (obviously) the removal of the compressor, a task complicated by the lack of space and maze of pipes, wires and assorted engine parts.

What follows is a guide for removing the windings in-situ (that is, without removing the compressor) and thus does not require draining the system (and a subsequent re-gas).

Sources:

This thread by “Jax”.

This web page (translation) whose images I have reused where noted.

NB: Nissan used more than one supplier and/or type of magnetic clutch assembly. The markings found on my aircon assembly were as follows:

506491 -

??-12V

Diesel Kiki Co. Ltd.

Ogura Clutch Co Ltd.

I am aware of at least one other assembly which requires a slightly different methodology (as noted at the appropriate stage below). Your mileage may vary.

Required Tools:

1. A ratcheting wrench with 8 through 14mm sockets.
   
2. Three M5 set-screws with at least 20mm of thread. I used these 40mm set-screws:
   

   

   
   

3. Circlip pliers. You may need both a straight and offset (bent) pair of the external type (they need to open quite wide). You want the variety that open as you squeeze the handle closed.
   
4. Assorted screwdrivers.
   
5. A hammer.
   
6. A jack and stands.
   

Prerequisites:

1. Jack the front of the car up. Ensure that you only use appropriate jacking points so as to avoid damaging the chassis rails or other components.
   
2. Make sure that you take necessary precautions (such as axle stands) to ensure your safety should the jack fail whilst you are under the car.
   
3. Remove the front undertray/protector.
   
4. Drain and remove the radiator.
   

Procedure:

1. Locate the airconditioner pulley. From the front of the car it will be the lower right pulley.

The aircon pulley. Note the power steering line sitting in front of the pulley.

2. Remove the bracket that supports the power steering lines. The bracket is held in place with one bolt located near the tow hook on the passenger side. This isn't strictly necessary but will give you more room.

The power steering support bracket. Here I have already removed the nut that holds it in place.

3. Take a close look at the aircon pulley. You should notice that on the front of the pulley is a plate (see the first picture); henceforth I'll refer to this as the "clutch pressure plate". The pressure plate has a large triangle in its center. In the middle of one of the edges of the triangle is a notch; you use this notch to hold the pulley in place whilst you remove the centre bolt. I used a large screwdriver braced against a part of the chassis whilst my dad undid the bolt; one of the pages I linked earlier under 'references' used an open ended spanner. Depending on how tight your aircon belt is, you might also find it helps to keep the pulley in place a little (I didn't).

The clutch pressure plate with center bolt removed. Note the arrow pointing to the notch in the triangle.

4. If you haven't already noticed, there are three small holes surrounding the central nut position on the triangle.

These are the three holes for the set-screws.

These three holes are tapped and are used to force the pressure plate off the pulley. Break out the three 5M set-screws and screw them in; just use your fingers at first to make sure you don't end up cross threading the holes. Do them up in a pattern, a turn or two per set-screw. Repeat until the plate begins to separate from the pulley (it might take awhile, but it will start to happen). You might find it useful to place a flat-head screwdriver in the gap that forms between the pulley and pressure plate and apply some force to try and pry them apart. After a couple of minutes of turning the screws and prying action the pressure plate should finally pop off the pulley:

The pressure plate removed. A nice view of where the set-screws go in.

Pressure plate side on. Note that set-screws with at least 20mm+ of thread are necessary for obvious reasons.

5. You should now have access to the pulley itself. The pulley sits on a threaded shaft and is held in place with a circlip.

It was very hard to get a photo of the circlip in place. The arrows point roughly to the circlip's tabs.

You shouldn't have too much of a problem getting this circlip off as long as you can get the pliers on to it. I used slightly offset circlip pliers for this one. The trick is to try and lift one of the edges out of the groove it sits in as you open the circlip with the pliers. I found it easiest to lift an edge and then jam a small screwdriver under the edge; I then ran the screwdriver around the circlip forcing it out of the groove. With a little luck it should pop out and the hardest task will be trying to find where it landed

6. Undo the aircon belt tensioner. The tensioner assembly sits on a threaded bolt. You will need to undo the nut (just enough to loosen it) on the front of the tensioner and the threaded bolt on which the tensioner assembly sits. Remove the aircon belt. If you need the extra room, consider completely removing the tensioner (I didn't).

7. Remove the aircon pulley. Use a large flat-head screwdriver behind the pulley and try prying it slightly in a few different spots. If its difficult, a couple of gentle taps with a hammer should help pop it off.

Here you can see a screwdriver being used to pry off the pulley. Also note the tensioner bracket attached to the bottom-left of the aircon unit

(This picture is sourced from here.)

Pulley removed with circlip placed on top for reference.

8. You'll finally have access to the windings. They will look something like this (I was just too grubby to take a photo at this stage; as you will see in later photos my windings have an epoxy coating) :

(This picture is sourced from here.)

The windings are also held in place with the circlip, although larger in size than the circlip holding the pulley. I warn you now: I found this an absolute bastard to get off. This is the hardest part of the whole removal as the circlip sits inside the inset area of the windings making it hard to get the pliers on and (at least in my case) the circlip is very strong: I nearly broke one set of circlip pliers and broke another, bought a third super expensive pair that didn't fit, and had to customise a set of pliers with a file. Because of its size you also need pliers that open a substantial distance. So the moral is: don't expect this to be easy and don't use that antique set of circlip pliers your long-dead great grandfather passed down through the family and to which you are sentimentally attached.

Use the same procedure as before: try and lift an edge out of the ridge whilst you open the circlip and then stick a screwdriver in the gap. You'll probably need a small screwdriver at first just to get something wedged in there, but such was the strength of this circlip that I bent my small screwdriver and needed a very substantial one to actually get the bastard off.

NB: "Jax" mentioned in his thread that there is at least one other system used for holding the windings in place. As he notes, the alternative version secures the windings with "... 3 philips-head screws onto the alloy housing of the compressor. I would suggest that a screwdriver bit adapted into a ratchet socket handle would be ideal as slipping out of the slot in the screw head could damage the slot and make removal very difficult".

9. With the second circlip off its time to remove the windings. There is a wire that runs from the back of the windings to the top of the aircon compressor where it runs through a small holder before ending in a plug. Unplug the cord. The holder uses a small piece of plastic to clip the cord in place: simply push the plastic clip forward towards the front of the car and it should pop out of the holder and the cord can be completely removed. Remove the windings.

The windings, removed.... finally. Notice how deep the inset area is.

A closeup of the windings cord and the plastic clip that secures the cord in the holder on top of the aircon compressor.

Windings with circlip placed on top for reference. Apologies for the over-exposure (and thus lack of depth for the inset area).

10. Make a note of all markings on the aircon compressor. On my unit there was a little label on the front of the clutch pressure plate which read:

506491 -

??-12V

Diesel Kiki Co. Ltd.

Ogura Clutch Co Ltd.

Where too next?

With the windings out you can now either replace them or have them 'rewound'. I have no idea of the cost of the replacement part or their availability. I opted for having mine 'rewound' as I didn't want to have to wait weeks for a replacement part to arrive. However, rewinders seem to be something of a dieing breed. After a lot of calling around I was finally referred to:

John Wallace

Wallace Automotive Airconditioning Pty Ltd

10 Galahad Crescent

Castle Hill NSW 2154

Ph: (02) 9894 0366

M: 0419 276 627

Rewinding is about $100-120, but may vary according to the model of windings. According to John it takes "three to four days" as the (original) epoxy coating has to be machined out and replacement coating takes two days to set. John also has a rig setup so he can test the windings in front of you; mine popped the 10 amp fuse straight away (but not a 30 amp fuse) indicating its working but drawing far too much current.

Depending on their condition you may also need to replace the circlips; I opted to replace both as mine were distorted from trying to remove them (particularly the larger circlip). Circlips are usually found at your local bearing supplier. I used Hooper Bearings in Mascot as most of the bearings places are way way out west (Hooper also has a delivery service if within Sydney metro for about $10). I dealt with Neil, who was very helpful and pleasant given I was purchasing such a small amount:

Hooper Bearings Pty Ltd

690 Botany Road

Mascot NSW 2020

Ph: (02) 96931200

M: 0418 282 130

The circlips for my aircon compressor were 35mm and 44mm. Note that circlip measurements are taken from the inside of one side to the outside of the opposite side and are thus not simply a measurement of the inner diameter. If you are unsure which circlips you require your best bet is either to take the circlips in to a bearings shop or to measure the shaft sizes so the bearing shop can work out which circlips you need. I would suggest you get at least two of each circlip so you have a spare in case you mangle or loose one.

Reassembly:

To reassemble, obviously go through the above steps backwards. I have only three points to make:

1. When putting the windings back on, be aware that there is a locating dimple on the back of the windings that matches an indentation on the top left of the face of the aircon compressor. Make sure you line these two up; you'll know when they are because the windings will only sit right against the face of the compressor when the dimple is in the indentation.

The locating dimple on the back of the windings.

2. It is very difficult to get the larger circlip (the one that holds the windings) in. It took me nearly 2 hours of trying. The circlip fits snugly in the groove in the shaft, and the groove is only fractionally in front of the windings; in other words, there is very little room. All I can suggest is keep trying and you'll eventually get there. I got about half of it in the groove and pushed the rest in with a small screwdriver.

Unfortunately, even telling if the circlip is actually in is difficult as you basically can't see it and will have to rely on feeling if its in the groove. A small angled mirror is a godsend and only a few dollars at an auto shop.

Thankfully the smaller circlip is much easier.

3. Both the windings and especially the pulley are a tight fit. I cleaned up the inside of the windings with some emery cloth and it fitted on without too much effort. The pulley was more difficult. As it sits on the threaded spline you have to be very careful not to strip the thread by applying force when the pulley isn't correctly seated/aligned. Try and push it on to the thread by hand and when your sure its actually sitting in the thread, apply more pressure. I had to resort to a lot of small taps with a hammer to get the pulley back on about 95% of the way. I put the centre nut back in and tightened it just enough to draw the pulley on the last 5%. John Wallace said to be very careful of applying too much torque to the centre nut as they are liable to snap. Once I had the pulley in position, I removed the nut and applied some threadlock, before tightening it up one final time; as per John's instructions, I only did the nut up so that it was firm rather than torquing it as much as I could.

Hope that's of assistance to someone

[paulr33]

well done, your efforts are appreciated. sorry for delay in approval

[lwells]

Updated

* Fixed a few grammar/spelling issues.

* Added details about the dimple on the windings and corresponding indentation on compressor.

* Added circlip sizes.

* Removed some incorrect info.

[ellie]

Awsome thread that will get used very often! The only thing i would add is the replacement of the pulley bearing as I had done this a long time ago due to not wanting to lose my R12 and both my friend and I have to now do it again due to our bearing becoming noisey. For the sake of a $ or 2 it would be well worth the insurance!

[lwells]

Awsome thread that will get used very often! The only thing i would add is the replacement of the pulley bearing as I had done this a long time ago due to not wanting to lose my R12 and both my friend and I have to now do it again due to our bearing becoming noisey. For the sake of a $ or 2 it would be well worth the insurance!

Thanks for the kind words, and its a good point you make. I checked the bearing in my pulley and it moved freely so I thought it unecessary.

Out of interest, did you notice when reassembling if one of the teeth on the pressure plate / compressor spline was different to the others? The Japanese instructions make some mention of a different tooth (ie. a locating tooth) but I certainly couldn't see one.

[ellie]

All the splines looked the same to me and I didn't have instructions but I do always check for things like that! May be it would apply to the other varient we didn't have.

[lwells]

Photos should be working again.

[CEF11E]

fantastic writeup. I have just bought a seized compressor and taken the windings out of it to put in mine. if they need rewinding it's all good at least it will save me from pulling the car apart twice.

You were not kidding about the circlips being a bitch. And also the pulley was REALLY tight on the compressor I pulled apart. it took several bashes to remove it.

I am a bit worried about having to do all of this while the compressor is on the car as it was hard enough when it was off the car

Does anyone know how maky ohms the windings are supposed to measure? The set I just pulled out measured 3.5 Ohms. If I need to I will have them redone but if they are supposed to be close to 3.5 I may not have to get them rewound.

Thanks

Edited November 8, 2006 by CEF11E

[lwells]

snip

Glad you found the writeup handy

To be honest, apart from the circlip business -- which is one of those 'could be 5 minutes; could be 5 hours' jobbies -- the rest of the procedure is not too difficult, just a little time consuming. Certainly helps to have a mate around.

No idea on the ohms: all that electrical stuff is gibberish to me. People start talking amps and ohms and the eyes glaze over You could try giving John Wallace a call (number in first post) and say your trying to work out if the windings are dead .... he seems to know his stuff when it comes to aircon windings.

Edit: Re: getting the pulley off, mine needs a few solid knocks but it wasn't too bad. You could try soaking it with WD-40 or some other lubricant (e.g. Penetrene) for a couple of hours.

[Rossman]

this DIY was very useful as i just had my coil windings re-wound. compressor goes back in this weekend, hopefully all will be sweet once the system is gassed up early next week.

for those in need of a place who will re-wind the coils i highly recommend.

RAPID REWIND

located Rocklea, Brisbane, QLD.

(07) 38752498

ask for MARK - very friendly and helpful guy.

- ROss.

[predator]

good guide ..

Question: Will the aircon also blow fuses when there is no gas in there?

[Keeper]

how can we get the pics back?

[hrd-hr30]

the pics are still in the page linked link at the top of his post. you just need to figure out which one he's referring to in the description, which is pretty straightforward.

I know its a year old now and he may not see this, but good job on the write-up lwells.

[Keeper]

this is the same procedure to follow if you need to replace the bearings in the pulley, just stop once the pulley is off and take it too and engineering shop, cost me $20 in labour and $20 for the bearing to change it over.

[lwells]

how can we get the pics back?

Hi

Seems like the pictures are working again? Sorry I didn't see your post/PM, I moved house/state, new job, etc and forgot to update my SAU details.

predator: I would doubt it would blow fuses just for having no gas. More likely it just won't blow cold air

hrd-hr30: Thanks.

Cheers,

Lucien.

[-==L=a=N=c=E==-]

Great writeup lwells, just used it to replace my coil as well!

A couple of notes which you might have to add.

When you remove the pressure plate, be sure not to lse the spacing washers which is on the inside of the splined area, these are spacers to allow the pulley to freewheel when not engaged. Without these washers, when you assemble it, it will be constantly engaged.

Also, this can be done with the radiator gear in, just requires a bit more paitience.

[rb180]

from another thread

What happened? Magnetic Clutch windings ere "cooked", and though still working,draw too much current, and blew #10 fuze.

At the time,not knowing what the problem was, replaced fuze. Air/Con worked for a while, then blew fuze again.

Same thing happened with me. I replaced fuse 10 and the aircon worked fine for a bit then i smelt something funny and found that fuse 10 has melted. So i tried to pull it out and only 3/4's of it would come out which leaves 1/4 of it stuck inside still.

Anyway from reading the thread I'm guessing the windings have been cooked like you guys have said was the problem with yours. I'm taking the car to an auto elec as i would have abit of trouble performing the "R32 Gt-r In-situ Airconditioner Windings Removal" DIY. So what exactly do i tell the auto elec is the problem? Is it as simple as telling him i need the windings on the comperssor rewound? and can anyone suggest someone who would be good at this or has done it before? I dont mind paying good money for a good job. Any help would be great thanks. oh and Btw im in Melbourne, Victoria. Cheers

[mark32gts-t]

Has anyone used RAPID REWIND located in Rocklea to have their windings rewound? What do they charge to have this done? Cheers