S2 Avant -93

[Antsa]

Now that the doors are all painted, the insides got the sound deadening treatment. You can clearly see by the white spots how the oem sound deadening was made.


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This is the product that I used

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Butyl mat laid down. A roller is a must have tool when installing this.


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Foam liner was laid on top of the butyl mat and the crash bar attached

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Rear doors were done too. They still had the original sound deadening on. A little warming with the wifes hair dryer and with some help of a steel spatula they came out pretty easily. The leftover glue was soaked with thinners and wiped off.

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Done

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[Antsa]

I also had a little bit of work done to the rear light. I bought this second hand and it had some cracks in it as usual. I tried different methods to fill the cracks and the best was to use windshield repair resin. After several filling attemps the excess resin was scraped flush with a razor blade and then the whole light was wet sanded, plastic primed and clearcoated. It's not perfect but it's definitely better that before! Maybe next time a little bit of red tint in the resin would yield even better results?

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These pictures are taken after the clear coat.

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[Filip_FIN]

Looking good

[89 Coupe]

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Are you planning to do a cut out and support it for the avant boot handle like factory or will you use a sedan boot lock push to open and modify the lock rods to suit?

I have purchased a 90 sedan taillight center garnish just recently and wondering what is the best method for opening the boot while also looking good. I have a c4 s4 matching opening handle already...

[Antsa]

My car actually has one of these already fitted. The boot open handle had a little surgery, so you can pull the handle enought to open the boot without cutting the light.

[Antsa]

The ac of my has never been working and I think the issue is a leak in the system. The evaporator got changed some time ago and now it was time to check all the other components, so I took all the hoses plus the ac compressor out. The hoses are well past their best and are not available from tradition so I had to cut the compression ferrules of the hoses to reuse all the fittings and just replace the hose section.

The hose between the drier and compressor gave me a little hard time because all the fittings were siezed solid and when opened with force the threads got stripped from the hose coupling nut and also from the compressor. So I had to buy a second hand compressor just to cut away the suction side m28x1.5 fitting and then it could be welded on my compressor. On S2 the compressors back plate is different than any other Audi model so this was the only way.

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The aluminum nut on the fitting had also stripped threads so they had to replaced. The m28x1.5 threaded brass nut is from a plumbing cataloque. To replace the nut the fitting had to be cut in half and then welded back together. I had two of these made but the other one had so severe pitting after the welding so i decided is best not to use it. Fortunately I was able to find a couple of good condition used AC hoses from Audi 80 that had the excact same fittings that can be cut out and reused.

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Ready to be sent for vapor blasting.


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[Antsa]

Compressor parts are back from vapor blasters so it was time to put it all back together. I did the assembly on the dining table

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I broke the needle bearing in the front casing while removing it for the blasting, so I had to buy a new one. Some threaded rod plus nuts and washer were used as a installation tool

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Bearing fully home

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The front casing also carries this thrust bearing. It has three parts. Two "plates" (other one already installed on the shaft and not showing here) and the actual bearing. The bearing in sandwiched between the plates and this system takes care of the axial loads in the compressor.

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The center housing carries the rear thrust bearing

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[Antsa]

The shaft and the pistons were put in

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And then the center housing was placed on top of the front housing with new seal in between

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The two halves got gently pressed together using these clamps while taking care that the front thrust bearing stays in place. The locating pins are tight so these can't be pressed in by hand.


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Here is the valve body and the valves. Valve body is little dirty but it got cleaned after taking this photo


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New seal and the intake valve plate were installed next. If you ever use this post as a reference, please note that the seal and the valve plate are the wrong way round. The seal goes in first follwed by the valve plate. I noticed this only after completing the assembly and I had to strip the compressor down again and fix my error. I also forgot to take a new picture where everything was in correct order.


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Valve body and exhaust valve in place

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Followed by by a cover for the exhaust valve and a new seal


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And finally the rear cover

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[Antsa]

New front seal got installed

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Clutch coil back in

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And finally the pulley

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[Antsa]

It's a amazing what vapor blasting can do Compared to the before pictures these parts look almost like new. Okay, I had to use the old pulley and clutch cover but the rest looks pretty nice

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[Nuvo]

A first class job as ever and great pictures detailing your work. A perfect how-to guide to follow.

[S2_avant 19930325]

I believe you should paint it .. or it will start a corrosion on the surface ,, the surface is blasted .. so it raw .. nothing to protect it ..

[Antsa]

Yes the bare aluminum does corrode pretty quickly, however the blasters told me that they have used some sort of anti-corrosion stuff right after blasting. I think maybe acf-50 or something like that. Hope it is enough to keep the corrosion away while the compressor is stored.

I'm not a great fan of painting these because the painting takes off the oem feel a little bit. I was thinking of redoing the acf-50 treatment before installing or maybe doing a clear ceramic coating?

[S2_avant 19930325]

For storage that will work ... i did not know there is ceramic clearcoat. I have looked and talked to a lot of paintrrs and shops for 2k clearcoat for aluminium.. but i seems there is not any good product for it .. then i mean a good tested product that does not goes yellow and keeps quality. Dont want to google the answer ?. I trust painters and people that have worked with it for a lot of years.

[Antsa]

What I have found and would like to try is a Cerakote MC-5100, which should work on bare aluminum surfaces. However I have no personal experience with this.