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| Joined: | 03-12-2005 |
| Location: | Kingman, Arizona USA |
| Posts: | 532 |
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When I finally got around to doing something about my car's suspension, I first installed Superpro bushings in the lower rear arms, as mentioned elsewhere on this board. The new bushings firmed up the car's rear end tremendously, and the comparison between front and rear made it quite clear that the front was in desperate need of attention. Since most cars with solid rear axles handle best when the front suspension is more stiff than the rear, I elected to install Delta's urethane bushings, as the Superpro equivalents would seem considerably softer. I also acquired a pair of KYB front shocks to replace the (probably not original) Girlings, which were showing signs of being worn out.
A study of the shop manual, and SportsRodder's instructions as posted above, gave me a good idea of the extent of the work and how to perform it. I estimated that the job would take about twelve hours. That was absurdly optimistic. Due to several problems found during disassembly, and to a few mistakes on my part, the job ended up taking more than sixteen hours. Also, there were time limits on how long I could have the car up on stands in the driveway, and consequently I was not able to abrasive blast and paint the suspension parts.
My problem areas.
First, and most annoying, the 1/4" bolts holding the brake hose support brackets to the spindles were installed from the disk side, just as shown in the shop manual drawing, and therefore were inaccessible until the brake disks were separated from the spindles. This made it necessary to undo the brake lines before the calipers could safely be moved aside, and to clean up the brake fluid that flooded out before I could cap things off.
Second, I found that the lower arm fulcrum (pivot) bolts had been inserted from the front of the car, apparently when a PO serviced the front end at some time in the past. With the bolts installed in this manner, it is difficult or impossible to remove them until the steering rack is separated from the crossmember. Then, when I put the rack back in place, the steering wheel lock elected to activate for the first time since I've owned the car, leading me to waste more than an hour in trying to determine why the steering had suddenly frozen, before I remembered that the lock was present.
Third, the steel tubes for the front shocks' lower pivot points were rusted to the associated bolts, and I found it impossible to separate these bolts and tubes by any means not involving physical destruction of parts. These tubes are necessary, but new ones are not provided with the KYB shocks.
Finally, one of the shock absorber upper bolts was found to be worn partly through, presumably due to its being loose at some time in the past. I replaced this bolt, and its undamaged mate on the other side of the car, using quality fasteners from the local hardware store.
Other comments.
Removing the upper arm bushings turned out to be quite easy, and I managed this using a threated rod, a receptacle, and a couple of nuts. Delta's bushings require re-using the metal shells from the original factory bushings, but since these shells generally are fixed rather firmly in place due to rust, this is a feature, not a fault. Using the provided sticky grease, these bushings and their steel tubes can be pressed into place by hand.
Removing the lower arm bushing was a bit more difficult. I found it easiest to drill through the rubber in multiple places until the hollow steel tube could be removed. Once that was done, I cut through the shell in a couple of places, and finally drove it out with hammer and chisel. As with the upper bushings, Delta's lower bushing, farside ring, and steel tube all went in with just hand pressure. I'll note here that Delta provides an instruction sheet stating that it's important to insert the bushing from the face having the 'bulge' or welded joint, and that the taper on the farside ring must face away from the arm.
(For Superpro bushings, the upper arm bushings come with their own metal shells, necessitating removal of the original shells. For the lower arm, the bushing is a three-piece unit -- two plastic parts and a steel tube -- whose parts are inserted from either side of the arm. I'm told that the upper bushes require a vise or press for installation, but that the lower ones go in by hand just like Delta's.)
If you want your suspension adjustable for camber, the holes for the hardware retaining the upper ball joints can be enlarged with a round file, cutting toward the centerline of the car. An elongation of 0.040" or so should provide about half a degree of adjustment range.
The securing nuts for the upper and lower ball joints need to be torqued at the time the suspension arms are reattached to the spindle. This is especially important for the lower ball joint, as its securing nut is not readily accessible once the steering arm is in place.
The steering arm uses two special bolts of different lengths, with the longer bolt going to the forward (tie rod) end of the arm. The bolt heads are on the disk side of the spindle, and hold the circular grease shield and backing plate in place.
The factory used a 1/4" bolt inserted from the disk side to clamp the upper part of the grease shield and backing plate to the spindle, as well as securing the brake hose support bracket. However, with the bolt installed this way, it is not possible to undo the support bracket, and it becomes necessary to open the brake line if the caliper must be moved. I elected to relocate the bolt to the exterior side of the backing plate, where it now serves only to retain the brake hose support bracket. I could have used a 1" long 1/4" bolt installed from the disk side, and held the brake hose bracket in place with a nut, but this did not seem necessary as the shield and backing plate don't move enough to interfere with anything.
I'll note here that the grease shield, Jensen part number 93241, is shown in my parts book as being used only on pre-1974 cars. I have no idea why it was present on my car, which has a door date in May 1974.
According to the parts book drawing, the stock road spring installs with its flattened side facing down. Things look a bit odd when the spring is fully extended, but as there's nothing in the shop manual to contradict the drawing, I must assume it's the correct way to do things. Perversely, my car had one spring flat side down, the other flat side up, thanks either to the factory or a PO.
Getting the shock brackets to line up with their mounting points in the lower arm while simultaneously forcing the castor rod into position is quite difficult. I found that using a threaded rod and a couple of nuts to pull things together helped considerably. If the tape holding a KYB shock in the compressed position should break, one needs a second jack to compress the shock enough to get everything aligned. This gets awkward, but it can be done. Eventually.
When reinstalling the caliper, double-check the presence of a thick lock washer on each bolt. Without these, the caliper will 'float' on its mounting hardware, which can result in unexpected pulling to one side or the other whenever the brakes are first applied.
Once everything is together, one should remove the jack from beneath the suspension arm. For KYB shocks, this should cause the securing tape to self-remove; if not, the tape should be cut away. Next, work the brake disk throughout the full range of its steering motion, and verify that there is no chance whatsoever of any interference between the road spring and the brake plumbing. Often it will be necessary to bend the bracket and brake pipe to ensure this.
On the road.
After a couple of test drives, I have two words to describe the car's suspension: taut, and quiet. The front end seems to be completely free of undesired slack and flex without being excessively harsh, while the rear is pretty close to what I consider ideal compliance. The only non-driveline noises I've noticed so far seem caused by body flex effects. The steering is subtly different, too, but I'm not yet sure if this is related to the new bushings, or to a need for an alignment.
Last edited on 09-03-2005 03:31 pm by Mark Rosenbaum