A/C Compressor Removal

[TJ 450]

While I have all the gear off the front of the engine, I would really like to remove the A/C compressor and thoroughly clean the area, as well as replacing the insulation on the A/C lines properly and possibly rebuilding the compressor/changing seals. Is there any precautions I should take into account while doing this?



Tim

[CraigS]

No precautions, but it is a real bitch of a job. Try breaking the lines at the join that you can see. It will not be easy though. Getting at the bolts is also not easy, but there is no easy way that I found. You have everything out of the way on top that you can, but I found that removing the covering underneath made access a little easier. It is held on by 3 bolts and it also a good opportunity to clean this up as well. You will see what I mean when you climb underneath.

[Big_Richard]

.

[CraigS]

You will be able to get a reconditioned unit for the amount PB mentions to rebuild it. For example,

http://www.ryderfleetproducts.com/cgi-bin/ryderfp/products/srm/oid/128198/pn/AC-Compressor-A6/erm/product_detail.jsp

Admittedly, this is a US ad, but I did receive quotes of around $400 when I looked at mine. Are you using R134a at the moment, or considering changing while it is out ?

[TJ 450]

At the moment, the system is kaput... complete with the original receiver/drier. It is still an R12 system as well. I'm expecting to have to replace hoses etc, but I'll start with the compressor. I also have a spare evaporator and expansion valve if that needs to be replaced (hopefully not).

Sounds good, did you get the seal kit in Perth as well, PB?

Tim

[s class]

TJ, it looks like that right front sphere has a green dot - if so it belongs on the rear of the car......

[CraigS]

The compressor will need to be flushed and oil changed to go to R134a. You will also need to replace the receiver dryer and the hoses. The rest will be OK.

Well spotted with the sphere. I wonder what's on the back ?

[TJ 450]

TJ, it looks like that right front sphere has a green dot - if so it belongs on the rear of the car......

PB noticed that on the weekend... I think it was someone's idea of economising, maybe they put a 2nd hand one on there, they're flat anyway.
The rear spheres are now new and have the green dot... I'll be replacing the front three and all four struts (or possibly just the balljoints, if I can find some reasonably priced replacements) after this cooling system & A/C revamp.

Tim

[koan]

The manual says to remove the compressor and bracket from the engine in one piece, no idea why though.

It's an awful job, rebuilding or resealing the compressor should be done while it's off, you wouldn't be wanting to take it off again.

koan

[Big_Richard]

.

[WGB]

Having recently done this job the major first step is to remove the alternator bracket which is bolted to the front of the motor for extra clearance.

The manual says to take out the compressor bracket, pipe manifold and compressor as one unit.

I took out the compressor and pipe manifold as one unit and the only difficult bolt is the one at the rear which is best got from underneath and was helped by removing the bash plate that protects the hydraulic lines from tyhe sump.

I had great trouble putting the rear bolt back because I used new bolts and couldn't get the rear bolt to start to on it's thread until I ground a small taper on the end of the thread - then it started first time.

I am a great fan of new compressors as they are not all that expensive , readily available and my A-C guy says that the recon units always have end float problems.

Now that my sustem appears to be working and is leakproof I never want to se it again.

Get a new receiver drier from AutohausAZ at $20 or thereabouts.

Bill

[koan]

I rebuilt my compressor in favour of purchasing another one because the rear cover of the A6 fitted to my 6.9 is unique (possibly all 6.9's), its the only one I've ever seen that doesn't have a valve screwed into it. I have a feeling it was deleted for a reason, possibly because of space constraints or the routing of the piping.

Exactly my experience. The change over compressor I was supplied had an overpressure valve sticking out the back that prevented the plumbing fitting back on. The valve was replaced by a screwed in plug.

There are several versions of the backplate with provision for various valves or switches.

I'd go for a rebuilt unit - unless PB is in a benevolent mood , there again my c/o unit leaked from around the backplate after 12 months and I had to do the remove and refit again.

I took out the compressor and pipe manifold as one unit and the only difficult bolt is the one at the rear which is best got from underneath and was helped by removing the bash plate that protects the hydraulic lines from tyhe sump.

The bolt I had trouble with is the one half way along the box section piece of the bracket that screws into the block, just about in-accessable from either top or bottom.

First time I took the compressor off the hard to get to bolts were only finger tight no doubt due to a previous "she'll be right mate" approach.

koan

[Big_Richard]

.

[WGB]

I know PB has the ability to recon them inexpensively but what is the cost of an exchange reconditioned one?

Maximum price for a new one is about $800 and they can probably be found for much cheaper than that.

I must say if I ever do it all again (and I have now reconditioned two M-B systems) I would go for Hychill and do it myself but I hope to not have to go that way again and a few hundred dollars is peace of mind.

Bill

[TJ 450]

I'm seriously considering the hychill option, as I would rather charge the system here than take it to a shop. I'll be removing the compressor on Saturday and will consider the exchange option as well... it could be quite reasonable by the sound of things. Did your recommended A/C specialist have recon compressors available, Bill? I know Veale Auto Parts is the agent for Hychill, but will they have all the required accessories such as schrader valves, PAG oil, gauges and fittings etc as well? It would be good to go to a one-stop-shop for all those sorts of things.
Thanks for all the info, guys. This will be quite a learning curve.

Tim