Renovating Scarlet’s Front Suspension – Control Arm, Kingpin Assembly & Shocks
Most of my stories about Scarlet, the 1959 Austin-Healey “Bugeye” Sprite begin with the statement: “I plan to repaint the engine bay . . “ and this one is no different. With the Bugeye up on jack stands and the wheels off, I began removing all of the engine’s accessories (starter, generator, radiator, etc. ). The final step was to inspect the right (passenger) side front suspension prior to removal.
One of the first things that I noticed was that the rubber coil spring buffer had fallen and was resting on the bottom spring tray. These buffers are there to prevent the coil spring suspension from bottoming out so I wanted to get it reinstalled. So, the spring had to come out!
With the spring out I was able to inspect the upper cone-shaped spring mount located under the shock-absorber mount. It was quickly evident that water had gotten in that cone and rusted out the mounting hole to the point that the rubber spring buffer had simply fallen out.
With the spring’s tension no longer there, I noticed the A-Frame (wishbone / control arm) bushings were completely perished and that meant the front suspension was coming out!
Here's what I did to take it apart:
In anticipation of issues removing the control arm, I sprayed lots of lube in all over the bushing area. Here’s where it pays to be patient and let the penetrant do its work. Forum advice is it will probably be totally rusted together a that a Sawzall may become your best. There is room in there for a blade and it’s possible cut the mounting bold without hurting the suspension mountings or the wishbone.
I was lucky and managed to drive out both of the control arm’s mounting bolts. That’s pretty amazing, considering the condition of the fulcrum bushing in the control arm. As noted above, the control arm bushings were knackered to the point the only the metal bushing inserts remained. She must have had a tendency to clunk, shake and wander all over the road at any speed.
Tip: Prior to cutting it apart, check the kingpin (swivel axle) for movement front to back. The pin should be free to rotate on the same axis as the fulcrum pin but there should be no front to back movement. Scarlet's kingpin was thankfully in good shape.
I carefully examined the control arm for cracks and tears around the mounting holes for the metal bushings. Again, to my astonishment, they were in remarkably good condition considering that all evidence of the “rubber” bushings was non-existent.
I put the control arm on the bench and in a vise and began the process of removing the swivel axle pin. A wedge-shaped swivel locking pin locks a flat side against a similar flat on the side of the fulcrum pin. As the front suspension goes up and down, the fulcrum pin now solidly connected to the swivel pin, rotates on the metal threaded bushings at the end of the control arm.
The manual says to simply unbolt the locking pin and drive out the swivel axle pin. More commonly it’s likely it will be totally rusted in place, or in my case, a previous owner had welded the pin on both ends! Using a small grinder on my Dremel, I was able to grind down the welds and then punch out the remains of the licking pin and remove the fulcrum pin.
The LH control arm had just the opposite issues! In that case, the locking pin remained intact and unbolted and was driven out with ease. Smooth sailing from there, right? Wrong again! This time it was the fulcrum pin that had wouldn’t release. I applied generous amounts of WD-40 and let it sit overnight but it would still not unscrew.
Thankfully, I have a nearby friend with skill, knowledge and tools to “persuade” most any metal object. A cutting wheel in a right-angle grinder managed to cut through the fulcrum pin and we managed to free most of it from control arm. However, at this point, the rest of the fulcrum pin still remained frozen in the control arm . Arrrrrrrgggg!
The solution involved welding a bolt to the end of the frozen fulcrum pin so that we could simply unbolt it. Not so fast! It seems, that was the original issue. We ended up getting out the oxy-acetylene torch and applying heat and torque to the pin and eventually it was extracted.
With the offending fulcrum pin removed, I worked in a new replacement pin and was pleased to confirm that everything was in alignment and that the threads were sill in good shape. This is important because both sides need to be exactly aligned.
Tip: It was at this point (both sides of the front suspension removed) that I came to the conclusion that it would have been more economical, certainly from a “time” standpoint, to simply have purchased new control arm pre-drilled for sway-bar mounting. Removing, cleaning, painting, etc. can take days! The front suspension control arm is $170 from Bugeyeguys.com
Part 2: or Renovating Scarlet’s Front Suspension – Control Arm, Kingpin Assembly & Shocks - Will continue with restoring the king pin assembly, the brakes and reinstallation of the entire assembly.
Comments