AC (aircon) bodgery? Expert opinions wanted*

[dieselnutjob]

The 806 has disgraced itself on it's way south (again).

 

Half way through France the AC packed up.

 

I checked the thermostatic relay which is the last switch before the compressor, and it was sending 12V to the compressor, but the compressor was not pulling in the clutch.

 

As an experiment I hammered some wedges of wood into the clutch, which seemed to work well for a an hour or so.

then all the wedges fell out.

 

The second attempt lasted about ten minutes.

 

The journey through Spain was pretty uncomfortable though luckily the temperatures were a little cooler than normal.

 

This won't last.  It will be 45 degrees in a few days.

 

So today I went right down to the connector on the compressor.  I connected a bulb up to the cable and it does light up when the AC is switched on.  Also the coil that pulls in the compressor clutch is completely open circuit.

 

I found a few bits lying around the flat

 

and did this

 

 

This also works.

 

I left the two tangs sticking out so that I can pull the bodge out with a pair of pliers if necessary, but now I am wondering.

 

I am thinking that I might be better to cut them off flush and wrap a long tie wrap round the clutch plate to stop the wire escaping.

 

I am think that provided it doesn't start slipping and squealing like a pig it will be ok.

 

I am thinking that I need to keep the button pressed so that the rad fan keeps running, and I need to keep plenty of air flowing through the heater blower to stop the evaporator from icing up (unlikely down here temperatures headed above 40 degrees).

 

Some questions:-

 

How do I keep the load on the compressor low?  If the car is cold and the heating is set to recirculate so that the evaporator is cold does this reduce load on the compressor?

 

What is the relationship between revs and torque load on the compressor clutch?  I am thinking that I don't want to rev it too much as I don't want that wire flying out, but I don't want it slipping either.

 

Lastly, the clutch plate is only about 3mm thick and the coathanger wire maybe 2mm, so I am thinking that only a thin tie wrap is going to be able to sit on that 5mm ledge but that should be enough to keep the wire in.  A metal CV boot clip is another possibility I guess.  An other ideas?

 

How likely is it that the whole thing explodes in a shower of compressor pistons and refrigerant?

 

[panhard65]

Is this an Hdi engine ? If so I would worry about it buggering the bottom pulley and the belt tensioner. The pulleys are rubber bonded to allow a little slip but having so much load on it all the time might cause it to fail. My other halfs 807 makes a hell of a noise if you start from cold with the air con switched on.

[Essex V6]

Opened this expecting a discussion and photos of tarted up AC Cobras - this forum ain't wot it used to be etc, etc

[dieselnutjob]

Opened this expecting a discussion and photos of tarted up AC Cobras - this forum ain't wot it used to be etc, etc

 

sorry. changed title to suit

[dieselnutjob]

The aim of this bodge is to drive around here a bit and get back to Blighty without it exploding.  If I was on my own I would just put up with the heat, but I'm not. SWMBO is complaining which means the inlaws here give me grief too.

 

Once we are home I can dig the wire out and probably sell of the 806 for just above scrap value.  It has 235000 miles and the only good panel on it is the roof.

 

I was thinking about that coat hanger wire, and if it comes loose I guess it will try to go back to being straight.  Then I will have basically a strimmer inside the engine bay.

 

Tomorrow I will go and find something to secure it better I think. 

[twosmoke300]

Also the ac should cut in and out as the evaporator temp sensor tells it to . May not be a problem if it's very hot it may overcool the system

[richardmorris]

It was the air con compressor that was responsible for the Citroen sm engines going boom. Not helpful though.

[dave21478]

If you really dont care about it, Im sure €10 to the nearest backstreet garage would see 4 blobs of MIG weld spaced around the pulley.

[FakeConcern]

Not sure if it's the same on your car, but I did this bodge on my Volvo V70 & it worked well.

 

http://forums.swedespeed.com/showthread.php?158177-I-ve-had-it-Help-with-a-Volvo-A-C-ghetto-clutch-fix

[mat_the_cat]

Also the ac should cut in and out as the evaporator temp sensor tells it to . May not be a problem if it's very hot it may overcool the system

 

In those sorts of temperatures my BX AC was on continuously, so would guess you'll be OK. I once had the clutch cut out on a long climb, and the rad fans come on full speed, so may have either been AC overpressure, or engine temperature triggering this. But for a car you're not attached to, I wouldn't worry...

[dieselnutjob]

The Volvo bodge seems to be a way of getting the air gap back within spec with the clutch still working as it should.  My bodge is to do with getting the thing permanently locked as the actuator coil has blown.

 

I thought I had this cracked, but yet again today it failed.  it's always the same, I bodge it up and it works, you go for a drive, and it when the vehicle is then stationary (like in a queue for a motorway toll) for a length of time, that's when it spits out whatever you put in there.

 

I went to pick up the wife n kids and the ac packed up. Underneath the car was the C shaped piece of coathanger and zip ties which it had pushed out of the way.

 

I think that stationary the pump must heat up a bit or something and the gap must open up, then things start moving and whatever I have jammed in there gets spat out.

 

I will have to invent something that will stay in place whatever.

 

Materials and tools are extremely limited.  Also I can only really work on this at night as it's too hot during the day.

[dieselnutjob]

also the compressor is really closeto  the subframe, and I'm not sure that there is clearance to get the clutch off with the compressor in place.

[Dead_E23]

Is the wire just bent into a C shape, or have you twisted the ends together?  (If it's not possible to twist them, perhaps you could bend each end back on itself and use a cable tie to pull the ends together?)

 

Alternatively, this bloke has videoed himself dismantling a compressor which I suspect is quite similar to yours.  If you can get a 14mm onto the centre nut (which looks in other videos to have a left handed thread), I suspect you may have just enough room to lever the clutch plate out (just as he says you mustn't, lest you break the springs), then you could recover the shims from behind it and reassemble, packing the outside with washers to jam it on.   The pulley and belt can stay where they are.

 

Even if that doesn't work it'll give you a couple of hours' respite from being nagged about it!

[dieselnutjob]

pulley and belt can stay where they are.

 

I don't know why I had a mental block over this.  One 14mm nut and the clutch plate was easily wiggled out.  I took me little while to figure out how to hold it still to undo the nut; in the end I just jammed a screwdriver between the clutch and pulley at an angle and put the jack under the end of it.

 

View with wheel arch liner removed

 

 

View with clutch plate removed

 

 

There was a very thin shim, put back on the other side as you suggested.

 

Modified clutch plate

 

 

I will wait until the hottest part of tomorrow and test it.

[dieselnutjob]

went up to 80mph then parked up and idled for 5 minutes and it still worked

next day still worked as well

seems to be sucessfully bodged.  I haven't put the wheel arch liner back because I know that if I do it will break the very next day. I also I bought a spare interior fan relay just in case

[Dead_E23]

Hurrah!    

 

Now we will discover if the clutch is just for passenger comfort or to forestall mechanical dramas.

[dieselnutjob]

It's more than that. If there isn't enough airflow through the condenser (such as if my cooling fan fails) then pressure in the system can get too high and damage the compressor, or even cause the evaporator to leak which I guess would fill the cabin with refrigerant?

 

I guess if it is too low if just won't cool well.

[Bren]

Give one of these a whirl

 

 

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