S2 coupe center driveshaft bearing and rear diff bush about to be done

[orsum]

I am about to send the S2 in for some work to be done does anybody have any advice before the work starts.

Center bearing.

am using the following
Quattro 80/90/S2/Coupe (B2/B3/B4)
Description
Center Bearings
Internal Diameter 30
Width 15
Hole Centers 133
Quattro 80/90/S2/Coupe (B2/B3/B4)
Product Code: CBA30133

The balancing will also be done. There is presently no vibration coming from the drive system but I feel its right to balance the shaft after working on it.

The diff bush that is installed is the original and if I use an iron bar to move it up and down and side to side it moves about 10mm. It is quite hard to move and it does return to its central position. I cannot see any damage to the rubber.

I have a Powerflex bush PFR3-107 which I bought a few years ago and will now be used.

Both jobs sound easy and are being done as preventive maintenance due to the age of the car and there is a slight knock gently coming off and going on the accelerator.

I understand this knocking is a common issue with our cars and it could turnout to be the diff that needs shimming, I hope its not.

[Mikes2]

Personal opinion - 1 job at a time. That way if there is an issue afterwards you can at least pinpoint the problem area. One thing you can guarantee is the increase in noise / vibration through the drivetrain when you fit the powerflex bush. Based on your description, I'd be leaving that well alone.

[orsum]

I fully agree on the one job at a time principle. Power flex bush will not be done until center bearing has been replaced.

I am aware of the golf 1 right hand side engine rubber mounting that can be used and that the mounting hole of off center. As I have the Powerflex I will try it after the centre bearing has been done. If does cause unacceptable vibrations I can always change it for the golf mounting.

[Bowie69]

When doing my prop, the hardest bit was getting the yoke off the shaft so I could fit the centre bearing, took a right beating with a lump to get it to shift.

Otherwise it is exhaust off, heatshield off, and cv bolts out to drop it on the floor.

Budget for new VAG spec bolts for the CVs and use the correct multi- spline tool.

Thumping from rear end tends to be the side mounts, which fail with monotonous regularity, and are only three bolts - I would change these first before even attempting the rear mount, which is more fiddly and requires a press/lots of swearing to get the old one out.

[orsum]

I have already replaced the side mounts as they had failed. Guess its worth looking at them again.

I am not doing the prop myself, sending the car to a specialist to have it done.

[Bowie69]

Cheap aftermarket ones tear themselves up in mere months....

I now use Porsche 912 engine mounts instead

[orsum]

Thanks for the tip.

Do you have the Porsche 912 engine mount part number.
Is it

Part Number:

19473JW

[Bowie69]

Found here, good seller:

https://www.buttysbits.com/product-tag/engine/

You have to grind the outside diameter down a bit to fit them, but we'll worth it. Alex on here does sell them pre-modified if that is your ilk

[orsum]

Pictures of the bearing I purchased

[orsum]

The center prop mounting has been done

Although I could not feel any vibrations but I did have a very small knock coming off and then on throttle I did not think the work was going to show up any real issues. I was more concerned it was going to be the diff mounting.

The mounting that came off was part number 8A0 521 113A. Note the shape of the bracket.

The bearing had failed there was lots of play and the bearing inside rubber was sagging quite a bit.

[orsum]

Then came the next shock. Both CV's had little to no grease left in them they were both in need of a service. Bearing in mind the car has only done 68,750 miles since new.

then the next shock the front CV cage was cracked

[orsum]

Why does this car fight me all the way

Now for some good news.

I called the supplier of the center mounting and asked if they had a CV for me. To my surprise they said they did and they have the CV boot that will suit the S2. The dust cover you can see on top of the box is the original that came off the car and was not require on the replacement CV.

[orsum]

I asked to see them balance the prop and to my surprise it was done as a completely assembled on what I think they called a three point system. The prop was out 50 grams at the start and they brought it down to 4 grams. I am not sure of the technical specification what is allowed.

Must also add the prop when they balance it spins very fast I thought I thought I saw 2500rpm on the the machine.

[orsum]

The drive home was very nice the ride was smooth and knock free. I can now see that there was vibration and the slight knock was all to do with the mounting and the CV's. Clearly I had become accustomed to the vibration and knocking.

This was a good result and an absolutely necessary repair.

[orsum]

Now comes the rear diff mounting. I took some picture while the car was on the ramp.