New to the forum guys and today i replaced the air con compressor and would be happy to guide anyone how to do it. Its easy and will take you around 2-4 hours inc tea breaks :-)
 

I bought my First Octavia mk1 tdi L&K estate few weeks ago. Really like the extras and space is not bad either. Great features and and love the ASZ engine as i have had this in a golf before.

 

After a week of buying car developed a strange noise on tick over and up to 10000 rpm. Did not like that noise sounded like a failing DMF. 
Drove car like that for a week and noise got slightly worse. Friday i looked around the engine bay and found nothing. Went back and looked at all the service history. Recent invoice was for alternator pulley but at the bottom it had a advice about play in Air con compressor pulley. So i fired the car again and paid close attention to the compressor asked wife to hold revs to 10k and the noise did seem to be coming from around the compressor pulley and the aux belt was worn really well too. I was not 100% sure that that was the problem but the day was lovely and dry and i could no longer stand that noise so decided to get the compressor out. Luckily i had a 2000 bora 2.0 parked on my drive that i was breaking. Initially bought  just the for the private plate :-)
 

Now i searched and searched online for ideas and easy was of getting to the compressor and liked the idea on getting to it from the bottom. However when i was about to start the job i checked the compressor part numbers on bora and octy and they matched apart from the last alphabet and sticker colour. Decided to get them both out on a bench so if they dont match i will at least be able to swap the pulleys.
 

I was breaking the bora so decided to get to the compressor using the simple way from the top by removing bits in my way. Man o man that worked like a treat. Compressor came out of the bora within 30 mins. MAKE sure you dispose of Air con gases responsibly.  So i decided to use the same technique on my octy.  Here it goes. 

• lossen the front driver side wheel nuts.
• jack the front driver side up.
• use axle stands for safety or double jacks.
• remove the wheel
• remove the wheel arch liner (good time to clean behind the arch)
• remove plastic that cover the pulleys ( use long screw driver to push down the plastic to remove)
• Remove the alloy inter cooler pipe in your way.
• remove under belly/under tray
• move up to the top of the engine
• remove battery connections (make sure you have stereo code if your car has one. Mine doesnt)
• remove engine cover
• remove the brackey on top of alternator. 3 bolts ( holds engine cover)
• remove alternator and air con compressor connectors.
• take a picture of how the aux belt goes.
• 13mm spanner put it at the bit sticking out on tensioner and pull as much as you can with other hand while bending remove the aux belt from below. Sounds hard but its not.
• Remove alternator bolts and you will need a long strong screw driver or pry bar to pry it away. Do not take it out without disconnecting it. 2 nuts. One you have removed the nuts rmove wiring and take out alternator. (i used metric ring spanner. Normal might work too)
• Now remove the tensioner. 3 bolts
• keep making space as you go along by removing pipes from clips and tucking wiring from your way. Common sence
• Remove air con compressor pipes on the other side of pulley. 2 bolts and 2 pipes. MAKE sure Air con has been depressurized and wear gloves for safety
• remover the top bolt holding the air con compresor
• get down by the wheel and you will see the other bolt. after removing the second bolt go back to the top pry the compressor away and put it out. There is plenty of space to do that.
• my compressor pulley had serous play in it
• time to replace compressor and put everything back.
•  Put the compressor bolts back in. partially tight. Put it on a bench pulley facing up and tap on the bolt heads. Enough force to push the rings on other side of the head of the bolts to move back to the metal casing ( if you dont tap the compressor wont go in) very easy.
• connect the air con pipes
• now put the alternator, tensioner back and connect the connectors.
• now feed the belt (get a new belt its not expensive) from top. 
• get some one to pull the tensioner while you are by the wheel and put the belt on. Use power steering pump pulley.
• Make sure its sitting in its groves.
• now put all the things back and job done.
• Tools used were, Metric ring spanners, pry bar, ratchet and sockets, allen keys, trolley jacks, axle stands sorry cant remember the sizes i was rushing as i didnt know how long it would take and if it would work using compressor from a 4 year old petrol bora.

Fired up the engine and it was a sweet sound. No more of that horrible noise. very smooth

​Personally i would change the compressor as its so much easier and readily available. £15 - 25 for a used one.
I would not waste my energy and time on getting air con clutch/pulley etc and its more difficult changing air con clutch and pulley while its still in (thats my opinion )

I just wish i had taken pics but hopefully this guide will help you guys if you have any issues with your air con compressor.
Ask me any questions you may have.

 

Thank-you.

Helped me locate mine.