A/C compressor replacement?

[clydebuilt]

Hello all.

Our mk6 2.0 FWD has just had a service and I asked them to check the A/C as it's never worked since I've had the van. They've told me that the compressor is most likely kaput and will need replaced. Sooo, I'm planning on purchasing a replacement compressor online but would appreciate a blow by blow breakdown of the replacement process if anyone would be so kind. The Haynes book is in the van, which is still at the service station so I don't know if the replacement process is detailed in the book (it's unlikely I think).

I'm not a mechanic but also not an idiot so would like to give this a go - unless it's a nightmare job that needs specialist equipment and knowledge.

Cheers all!

[metalworker0]

Bit like replacing an alternator ... only you have a couple of pipes to bolt to it

Note; you need new o-rings ...which are green ones made specially for AC .

Once all bolted in place, then it's hand it over to the professionals to do the re-gas. as they have the gas and the machine to do it

That's if its strait forward and nothing else has failed which they will find ONLY during the re-gas ...as there are many parts to the system that can fail.

shown here

https://i.ebayimg.com/images/g/AEEAAeSw ... l1600.webp


All of which, if hasn't worked for years, will need new o-rings ..as well as the schrader valves (not shown in the picture ) they are the filler valves that contain tyre inflater type valves.

Note: if the radiator fan does not work, then the AC will not work,
The evaporator core (should it be leaking) is burred behind dash and usually requires dash removal, .... A massive huge job on most vehicles, that no one wants to do.

The gas in these systems is very expensive ,...and it leaks through holes ten times smaller than water would be able to. you have no way of testing for leaks until the re-gas, then they use dye and "black
UV light" to find the leaks.

all the best.mark

[clydebuilt]

Cheers for the response and the info - much appreciated.

Are there any quick and dirty tests to validate which components may have failed in the system? I'll need to speak to the service people to determine how they established that the compressor was knackered.

Cheers.

[andz327]

Like metalmarks tutorial mentioned there's a whole host of surprises could be waiting for you, the longer the system hasn't been working/no gas the more problems you'll have, but if this is same compressor as yours at this price its definitely worth taking the chance, fairly easy to fit if the driveshaft doesn't get in your way (cant remember seeing mk6 with A/C)
https://ebay.us/m/GYtmld

Sent from my SM-G990B using Tapatalk

[metalworker0]

Only if you buy a smoke tester that has built in air compressor.

see you tube videos "testing AC with smoke tester"

Tests on the compressor will consist of observing if its clutch operates... there is a drive pulley that free wheels, until the clutch pulls it in ... this may or may not, take place until its re-gassed and the radiator fan is operative. or to what gizmos and sensors are fitted to the system, that may cause non-operation, if certain conditions not met like charge pressure, the thermostat in the evaporator core etc

and if the compressor failed in a spectacular way ..its not unknown for it to deposit crap (metal swarf or rubber) in the whole system, requiring a flush out or complete replacement of components.

all the best.mark

[clydebuilt]

Cheers all.

This is all beginning to sound a bit terrifying. The whole system is an unknown integrity wise. I'll purchase a replacement compressor. Can the system be flushed while the compressor is removed to get rid of any crap in the system?

[metalworker0]

Flushing .I'VE NEVER DONE IT -- --- the knowledge for that is on your tube.

Take note; lots of idiots who don't know what they are doing.

Try "Rainman Ray's Repairs" channel for good info on AC repairs on youtube.

https://www.youtube.com/@RainmanRaysRepairs

all the best.mark

[MinorMatt]

If you unplug the electrical connector from the compressor - and turn the aircon on - if it has 12V there its worth looking at the compressor. If not you have a fault elsewhere.

You can use one of the aircon regas kits to check if there is pressure in the system - no pressure, no work!

Its also worth checking the airgap on the compressor. If you turn the aircon on with the engine running, give the end of the compressor a tap with something. If it starts turning the air gap is probably too big (should be round about 0.6mm from memory) and you can take the end off and reshim it.

[clydebuilt]

Thanks again all.

Right, once the van is back I'll check for 12v at the compressor connector and if so I'll give the compressor a tap to see if it starts turning.

I'll see if I can see if the compressor clutch is operating with the caveat that a multitude of sensors could be preventing this from functioning!

I'll have a look online for regas kits - any recommendations while I check out "Rainman Ray's Repairs" channel?

My concern is a historic spectacular compressor failure as I'm certain the service guy mentioned that there could be all kinds of material in the system because the compressor has failed

I'll buy a replacement compressor (https://ebay.us/m/GYtmld) as I'm pretty certain either myself or a garage will need to fit it anyway. Would I buy the green o-rings separately or are these part of the component?

Cheers.

[MinorMatt]

Thanks again all.

Right, once the van is back I'll check for 12v at the compressor connector and if so I'll give the compressor a tap to see if it starts turning.

I'll see if I can see if the compressor clutch is operating with the caveat that a multitude of sensors could be preventing this from functioning!

I'll have a look online for regas kits - any recommendations while I check out "Rainman Ray's Repairs" channel?

My concern is a historic spectacular compressor failure as I'm certain the service guy mentioned that there could be all kinds of material in the system because the compressor has failed

I'll buy a replacement compressor (https://ebay.us/m/GYtmld) as I'm pretty certain either myself or a garage will need to fit it anyway. Would I buy the green o-rings separately or are these part of the component?

Cheers.

Im not suggesting you actually use a regas kit - but they have pressure gauges which show you whether there is gas in the system. (or you could do the naughty thing and press the middle of the valve in...)

[metalworker0]

Some tomes the seals and o-rings do come with the new compressor sometimes not.

The mechanics who do this work regularly, have boxes of O-rings, including boxes of new schrader valves. ...note all the 0-rings will be different sizes for each car ...and there are several designs of schrader valves ...that you'll only find out when you pull them out which a requires special tool... i mention the schrader valves as; its the number 1 cause of AC system loosing gas.

Rainman Ray has flushed systems on a few of his videos ......but he hasn't typed this in the title or description ...so finding the ones with a flush is impossible amongst the maybe 100 or so videos he has done on car AC system maintenance ..that are amongst 1500 other videos ..otherwise i would lead you strait to them.

ebay ..
The boxes (kits) of assorted 0-rings are available in green or purple ..a box is £7:50 upwards
The boxes (kits) of assorted schrader valves are £11 upwards for 100 piece includes extractor tools.

Flushing agent ..well never done it so don't know ..but appears to start at £24 for 500ml can, that is for the proper stuff .,.what ever that is

But net suggests brake cleaner will do ..then you have to blow it out
... i would imagine panel wipe "naptha" would also be ok ...but that is going to cost over £20 for the 5 litres you will need.

Then you are going to be buying a big syringe to pump it in ..

all will add up ... that says to me personally ..leave the whole job to them,

all the best.mark

[clydebuilt]

Thanks again all.

Spoke to the guy who was carrying out the service. His observations about the van's AC system:

Air con pump is seizing. Debris from rubbing gets drawn into air con system.

Need to replace the pump (compressor pump?) but debris could still get into the system. May need to remove pump condenser and evaporator and clean them. The evaporator is a bitch to get at as its behind the dash (dash out job?)

The guy had charged the system as the gas was low and switched the AC on. Compressor was clicking in and out so had a pressure problem. It was running and stopping instead of continuously suggesting that it was bunged up and seizing.

I was advised to clean the system with lots of brake cleaner as it evaporates because AC systems don't like moisture. Change the compressor and blow through all pipes with an air line then the brake fluid. The system is currently empty to allow this to happen.

Now I have the authoritative answer from the mechanic, what's the recommended course of action do you reckon?

Cheers!

[metalworker0]

well if it wasn't a camper van, then it would not be worth the spend.

You are possibly going to spend in excess of £1500 plus vat. As it is, your van is probably worth twice or even three times the amount of the same year ordinary van of that year, i'm going by by the looks of your profile picture with that statement.

it's up to you, the balls in your court.

Get a price and decide


all the best.mark

[clydebuilt]

Cheers Mark.

Yeah, the patient is our camper van. It can get sweltering in the cab when we are away in it hence the desire to fix the AC.

I'll put together an intial shopping list for parts as my other half's cousin is a time served mechanic who's willing to get involved.

* Compressor pump: https://ebay.us/m/eLi5sw. Comes with green o-rings.
* 5l brake cleaner: https://ebay.us/m/RKZ3EQ

Does the belt need to be loosened to remove the compressor?

Not sure where to get a big syringe to pump the agent into the system?!?

Was also wondering whether something like this AC recharge kit would work to check pressure after replacing and flushing: https://ebay.us/m/7kVGVV. No idea if the valve will fit the van - are these universal fit?

Cheers!

[metalworker0]

The belt has to be loosened to remove it .. usually a 1/2 drive ratchet is used on the tension pulley ..

..count the ridges in the belt some are 6, some are 7 ... that is also as important as the amount of ridges on the new compressor pulley.

KITS
no idea about the recharge kits ..the one you linked to has only one gauge, most have two (low and high) and the small bottle, well it looks like its meant for topping up and not recharging whole system.

The pro way.
The usual thing to do when starting from scratch ..is to create a vacuum in the system ..that's what a professional machine does, it then holds that vacuum so checking for leaks ..then it fills it with the correct amount of refrigerant ...the correct amount is usually displayed on a sticker found on the slam panel,under the bonnet. watch a few of rays videos .I've only ever seen the pro method ,...ive never seen anyone using the kits ..so cant advice .

Syringe
Enter words "large syringe " into ebay search ..there are plenty to choose from.
...you'll also maybe need rubber tubes and whatnot's to connect .... from car A accessory shop ...
OR an aquarium shop etc.

The Cleaner
no spec sheet found on holts site.. and not sure if this the old formulae ..but generally , environmental .."no this", "no that" ..means poor product!

Other search for spec SDS sheet, not sure if old or new - but if it says on it ...
main ingredients - Naphtha (petroleum), hydrotreated light - then its good product ..and i have another cheap source for coleman fuel for my camp stove collection

https://cdn.aws.toolstation.com/items/c ... -43710.pdf

all the best.mark