The one major area needing attention after the engine rebuild was the rear axle. All the various suspension rubbers were in pretty poor condition and had been on my list for some time. I decided that while the rear axle was out I would also fit a mild lowering kit and uprate the braking.
The first job was to remove the rear section of the exhaust, drive shaft, fuel tank, axle shafts, rear suspension struts and the trailing arms. The rear struts were discarded (well I say discarded, they were in pretty good condition and were put up for sale) as they would be replaced with the lowering kit. The differential was removed from the rear axle carrier which was then dropped out and I set about removing the old rubber bushes. There was very little over from the large rubber mounting bushes in the axle carrier, also the bushes in the trailing arms weren’t shot but needed replacing. Because they had been in for so long even a hydraulic press wouldn’t shift them, so I got the acetylene torch out and got them nice and hot 🙂 , most of the rubber burnt out through this process however and the workshop was full of smoke. It did manage to release them and they pressed out OK after that. The subframe, the trailing arms and the brake backing plates were then sent away to be blasted and powder coated.
While those parts were away I got on with some other work.
Axle shafts and CV Joints
The CV joints from the axle shafts were dismantled, degreased and thoroughly inspected for wear. They were in surprisingly good condition considering the age, there were no splits or leaks in the boots, although the grease was starting to dry out, and no wear on the surface of the grooves where the balls are held. To dismantle them you need a system to mark and store the parts so that they can be put back together in exactly the same position, so I usually create some kind of tray from a cardboard box where I can make cut outs to place everything as it came out. The shafts were giving a coat of protective paint and then using a rebuild set new boots were installed. The CV joints were reassembled and filled with the correct amount of grease as supplied in the kit. I then finished it off with new set of boot clamps.
Brakes
Although not bad the brakes needed to be uprated a little to compensate for the extra performance from the Miller MAF conversion. After researching various options and having realised that the budget was not a bottomless pit I decided to replace just the front discs and calipers with a set from an e32 740i. These are a little larger in diameter and substantially thicker. The calipers I bought used but the discs were new as most used discs have no meat on them anyway. While the rear calipers were also off I had the whole set blasted and then treated them with heat resistant caliper paint. They were then reassembled with a repair kit. The e32 discs are a straight fit on the e24 front stub axles and fit millimetre perfect within the shape of the backing plate. When you think about it the e24 disc seems a bit small for the plate. Brakes were reassembled and finished off with a set of Goodridge SS brake lines.
Fuel tank, pump and filter
The tank was in good condition and also surprisingly clean inside. After removing the lift pump (which had been replaced a couple of years earlier) it was washed out and given a coat of protective paint and underbody coating. Filter was replaced, of course, and the main pump was dismantled to see if it was clean and intact inside. For the re-assembly I used new rubber piping and new rubber isolation mounts as the old stuff was no longer serviceable.
While this whole underbody area was exposed I took the opportunity to inspect it for any signs of rust forming or deterioration of the underbody coating. I gave some sensitive areas another coat just to be sure.
Rear axle carrier and suspension re-assembly
The axle carrier was fitted with new rubber mountings, and the trailing arms with new rubber bushes, using my neighbour’s hydraulic press. Axle carrier was lifted into position and re-attached. The differential which had been cleaned up and painted was then fitted and the drive shaft installed. Wheel bearings were refitted in the trailing arms which were then re-attached and loosely tightened. They would be torqued up later on a lift with some extra weight in the car to set the suspension at the correct height. The new suspension parts were fitted followed by the refurbished brakes and brake lines. The last piece in the puzzle was the rear section of the exhaust and we were ready to fire it up again and test it.
Generally speaking a rebuild with new or serviced parts is pretty straightforward and this time was no different.
Below is a slideshow of some of the refurbished parts prior to and during installation.
