A2 Rear Axle restoration – my journey

[Alan_uk]

I'm waiting for the shocks. Ordered from APT but transpires coming from Germany. Seems to be stuck in customs in Essex. I hope it comes in time to fit before a long journey.

Meanwhile I dremel off the ABS sensor hex bolt head. I removed the ABS sensor but the remains of the bolt (C in the photo) wont shift using pipe pliers and mole grips - just gets worn away. Yes, it's had numerous dousings of Plus Gas penetrating fluid. Anyway, I concluded the hex bolt goes into the hub so if that gets replaced it doesn't matter.

But the hex bolt to the cylinder is more problematic. I dremel the head off (A in the photo) but it wont shift. I cannot figure out if the back plate has a raised area for this bolt. If not then I can dremel a bit more. Anyone know?

It appears that the cylinder bleed hole B is not fixed to the back plate.

 

[datsundrew]

You need to just give that wheel cyl a good bash with a hammer…..it’ll drop off

 

[Alan_uk]

I drilled out the hole and then it came off with a bash. The hole is 6mm I recall and it's just 4mm from the bleed hole. And the hole does not have a raised area at the back of the backplate so I could have dremelled some more.

When I got the hub off the near side had corrosion behind it. Water must have seeped between the hub and the axle arm. I post some pictures when the thunderstorms are over.

 

[Alan_uk]

Been away for a week but before I went I got all the bits off the old axle by drilling out the hex bolts.

The shocks arrived and Drew @datsundrew kindly offered to help me put them on. Great friendly guy with many interesting cars in his collection that he has restored.

Unfortunately the knocking noise has persisted so I added this to the list of things for WOM to look at (next post)

 

[Alan_uk]

Whilst on hols in the Peak District I visited WOM. This was originally planned to investigate a slight misfiring that occurs at high speed (50-60) and then accelerating. I've had this for at least 5 years. Sods law had it that on the journey up to the Peaks with much high speed running on the M4/M5 and M6 (except when in a traffic jam!) it did not happen. Marcus at WOM felt he could slightly sense it but as I had found nothing on a scan.

So Marcus looked at the rear suspension. He said that the noise sounded like the shock top mount although they don't fail often. He asked if they were replaced. I said I thought maybe in 2016 with a complete suspension change all round. I did not changed them last week as being metal they can't deteriorate. Wrong!! Marcus said they had an inner rubber. So we took the mount off and sure enough there was movement.

WOM could only get a single new mount at short notice, a Munroe, but WOM had an OEM one in stock that looked like the Audi rings had been burnished off. I must say Marcus really worked fast, WOM certainly know the A2.
The knocking noise has now gone, though the suspension is still firm and given the state of the roads I still get a rumbling at times but no more banging on uneven roads. The car was again a joy to drive on country A roads, just purring along taking bends with ease.

Hear are the old top mounts. No Audi marking so they must of been changed in 2016. Either cheap ones were used or the shock top nut was not tightened sufficiently. Note that I can't see any rubber insert. All that is visible is metal.

 

[Alan_uk]

Progress has been ad-hoc but here is an update since I got the 2 back plates off.

The rusted areas on the whole axle were wire brushed to see the state of play. I think it is OK to re furbished. Here's a typical result:

I then painted the whole axle with Kurust as a temporary protection.

The flanges where the hubs attach were pitted with rust, the nearside more so:

So I ground this away with a small grinding stone in a Dremel and then painted with Kurust:

This shows up some remaining pitting. I will need to check it is not above the surface.

I then made some end plates from 1mm aluminium sheet to protect these areas. Unfortunately when I went to fix with short M10 10mm Hex Bolts Fully Threaded I found the bolt threads all gummed up. I should have protected the bolt holes.

I then purchased some 12mm bottle cleaners, cut them short, and put them in a slow speed Dremel and with 99.9% Isopropyl Alcohol (and a face mask) cleaned the threads. This helped a lot but there was still debris in the threads. So I took a spare bolt and cut 2 slots at a angle so that when inserting the bolt is scooped up any debris. Known as a chaser thread cleaner they are expensive to buy. Here is the bolt next to one of the stub hub bolts.

That worked and I was able to attached the protective plates:

Note the small hole was drilled in error and will be filled with epoxy resin, hence the paper behind.

Before attaching a plate I decided to have a look inside the axle. See next posting.

 

[Alan_uk]

A recent post of someone who had replaced their A2 axle with a Polo one, remarked that the Polo one was filled with oil. I don't think A2 ones are. Here are typical views:

There is some surface rust. I think the white might be a zinc coating. My plan is to pour in a tub of Kurust, turn the axle back and forth and pour out the excess. I will be very difficult to spray an underbody protection or to pour in anything too thick. Suggestions welcome.

 

[Alan_uk]

I'm assembling the parts list for the axle restoration and seeing what is available. It's the small fittings and fasteners that are proving difficult. I intended to replace the handbrake cables, include the Y part (I already have that from a previous group order). The handbrake cables go via some brackets and I recently posted a question asking what they were made off, i.e. if steel they may rust.

Here are the parts with a picture of the new ones from Audi Tradition:

@kp 115 Kevin replied that they were zinc plated steel.

I checked under the car with an endoscope. The nearside one is more exposed and has surfaced rusted but the fixing bolt is OK:

Removing these is difficult as the fuel tank is in the way! Given that they cost 28 euros each and the bolts another 8 euros then they can stay for now! I sprayed some Kurust on and will treat them to some anti-rust paint with a long brush. The exposed handbrake wire looks very good so I will treat those with some grease (copper-grease?).

The offside is fine as it is protected by the exhaust heat shield:

Again this would be difficult to remove. There is something in the way as shown in the photo. I also noted some rusty clips. I'm not too sure what the cables/pipes are:

I'm now awaiting Drew @datsundrew to return from hols and help me remove the bushes. Meanwhile I need to find a company to shot-blast the axle and paint it. That's another decision to make: what sort of paint finish. Plus order the parts.

 

[kp 115]

I'm assembling the parts list for the axle restoration and seeing what is available. It's the small fittings and fasteners that are proving difficult. I intended to replace the handbrake cables, include the Y part (I already have that from a previous group order). The handbrake cables go via some brackets and I recently posted a question asking what they were made off, i.e. if steel they may rust.

Here are the parts with a picture of the new ones from Audi Tradition:

View attachment 111257

@kp 115 Kevin replied that they were zinc plated steel.

I checked under the car with an endoscope. The nearside one is more exposed and has surfaced rusted but the fixing bolt is OK:

View attachment 111259 View attachment 111258

Removing these is difficult as the fuel tank is in the way! Given that they cost 28 euros each and the bolts another 8 euros then they can stay for now! I sprayed some Kurust on and will treat them to some anti-rust paint with a long brush. The exposed handbrake wire looks very good so I will treat those with some grease (copper-grease?).

The offside is fine as it is protected by the exhaust heat shield:

View attachment 111260

Again this would be difficult to remove. There is something in the way as shown in the photo. I also noted some rusty clips. I'm not too sure what the cables/pipes are:

View attachment 111261

I'm now awaiting Drew @datsundrew to return from hols and help me remove the bushes. Meanwhile I need to find a company to shot-blast the axle and paint it. That's another decision to make: what sort of paint finish. Plus order the parts.

Keith

 

[Alan_uk]

Yesterday I filled the axle arms with Kurust. It quickly poured out the other end by the bushes but caught the liquid and put it through again.

Today I visited Drew @datsundrew where he once again helped me. This time he removed the old bushes. It seems a frightening process but I was confident in Drew as he has done it before. Thank you

I've been contacting shot blasters by email but none have responded....

 

[Alan_uk]

Note: reposted in the correct thread.

Final prep for shot blasting.

After Drew removed the bushes I wire brushed the housing. To the eye it looked OK but a photo shows rough surface but I'm reluctant to take any more away. Drew says that the poly bushes are very large but compress to fit the housing, so some wear should be accomodated. I took many measurements of the housing for the pdf mentioned below.



Next I made some wooden disks to fill the housing and protect them from shot blasting and paint.



Stan H had problems fitting Powerflex poly bushes, so I made a document to send to Powerflex to ensure I order the right ones. My brackets at 98mm are slightly wider than Stan's. I was using a manual calipers whereas Stan was using a digital one. I tried to fit the old bush between the bracket arms with the large shim but it was too tight and I had to wire brush the large shim.



So I then made some washers from an old CD to protect the centres of the large shims from paint.



Finally, I made some protective covers for the drum brake pads sliders (may not be the right word) as they appear to be brass. I used some thin aluminium sheet.

 

[Alan_uk]

Today I measured the old bushes and updated the pdf (new page 3). seems I need 69mm poly bushes rather than 72mm. Interesting the rubber pushes advertised are 71.5, 72 or 72.5mm - all of which seem too big.

Powerflex replied today to say they have withdrawn their A2 rear axle bushes pending redesign. As Stan @Stan H found, they did not fit. There was also concerns by Powerflex as to pitting on the washers/sims. Seems their poly bushes has more surface area contact with the large washers compared to rubber bushes. AT sell the washers at euro 28 each and they seem to be unpainted (maybe zinc coated)

 

[Alan_uk]

Some weeks ago I ordered lots of fasteners. It was quite difficult to find them at a reasonable cost. Have some guys in Latvia and Greece hoovered up all the parts and sell on ebay for extremely high prices? (e.g. £10+£7 p&p for a washer!)

Eventually I found LLL Parts https://www.lllparts.co.uk and ordered 36 fasteners. Today they arrived and the order was complete. Came to £66 including a very reasonable £4.19 p&p

There were a couple of fasteners they didn't have that I found at https://www.vwspares.co.uk and VW Heritage https://www.ebay.co.uk/str/vwheritage

 

[Alan_uk]

I saw some PSB Poly Polyurethean ebay made in South Africa and asked the ebay seller (problemsolvingbushings) to measure the length and send me a photo of the end against the large washer/shim:

The bush does not have a central protrusion on both ends - the end against the large washer/shim is flat. Therefore the total length is 91.5 + 9.8 = 101.3. Too long for the 98mm gap between my bracket jaws.

I have therefore decide to go for rubber bushes. The bush housing on my donated 2003 axle is 68mm so I will go for 69mm rubber bushes.

 

[Alan_uk]

Yesterday I blanked off the bracket jaws mating surface as I didn't want more paint on them or them shot blasted. I cut aluminium disks using a rotary disk cutter. Not brilliant at making perfect circles but a bit of filing rectified that. I replaced the earlier discs cut earlier from old CDs with ones made from aluminium. I also made some hooks so the shot blasting company can hang the items up for spraying. Plus some labels.

Today I took the axle etc to Booth & Son at Purton near Swindon for shot blasting, 2 part primer & 2 part gloss black top coat.

 

[Alan_uk]

Today I collected my refurbished rear axle. It was ready earlier but I have put my back out serverly. They were happy to load it into the A2. Back problems meant I've not ordered the new parts as I though I might wait a few days to the next credit card cycle!

After shot blasting they used 2 part primer and 2 part top coat. Total cost including vat is £242. I think this is reasonable. Labour rates at over £100 ph + vat but they gave a verbal estimate for each stage which they kept to and that seems to have included the paint.

They seem to have done a good job. I tried to take a photo inside the bracket holding the brake hoses and it is painted. Of course, painting highlights all the indentations caused by corrosion. I joked I would be back in 10 years if it didn't last. Not too sure I will be here in 10 years!

 

[simufly]

Have fun installing the new bushes!

 

[Alan_uk]

Have fun installing the new bushes!

Drew @datsundrew very kindly said he would help . He did his own axle refurbish recently and has the tools.

 

[simufly]

Drew @datsundrew very kindly said he would help . He did his own axle refurbish recently and has the tools.

What bushes are you using? Everywhere I tried was out of stock. I had to get a pair from AT courtesy of @Rickmeister

 

[Alan_uk]

What bushes are you using? Everywhere I tried was out of stock. I had to get a pair from AT courtesy of @Rickmeister

Oh dear. About to order today. Drew gave me a link to the ones he bought on ebay but they were 72mm and mine are 68 (or is it 69) mm.

Getting them from AT means a month's delay at least unless I get them shipped separately from the next group order.