Front-end refresh: To re-bush or not to re-bush?

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Last week, I described diving into the front-end refresh of my 1974 Lotus Europa Twin-Cam Special. Over and above the fact that the car sat for 40 years and literally had a wasp’s nest at the top of the right front suspension, I did have specific goals for the winter project.

1) Replace what’s obviously broken (one of the sway bar links) or worn out (the ball joints and tie rods, whose rubber boots had completely dissolved during the car’s long dormancy).

2) Disassemble and thoroughly inspect everything to unearth anything obvious that might be the cause of the car’s front-end shake at 65 mph. This included rebuilding the trunnions, as it would be foolish not to.

3) As long as I’m in there, disassemble the coil-overs and evaluate the almost certainly original front shocks, which are functional but really soft.

4) If it’s cost-effective to do so, lower the nose a little to set it where it should be without the U.S. federal headlight height standard.

5) Try to cost-contain the project, which is neither a restoration nor an attempt to turn the car into a track rat.

First, a note on the difference between summer and winter projects. When I delve into a project between May and October, I typically try to be almost brutally efficient. After all, during good weather, I want to be driving these cars. I’ll try to minimize downtime by ordering all the parts I’m likely to need before I disassemble things, and if I plan to replace fasteners like worn-out nyloc nuts, I’ll make a list of all of them I need and try to check off their purchase in a single trip to the hardware store. And I’ll have long wrenching sessions in the garage, sometimes working myself to the point of exhaustion to get ’er done. I’ll take great pride in the amount of work I’m able to knock off in a short amount of time.

However, once winter comes, the cars are jammed sardine-like in the garage, the door comes down, and the snow falls and blocks them in, projects have an entirely different rhythm. Since the cars aren’t going anywhere for months, there’s no rush. That, combined with the cold temperatures, makes me eschew marathon wrenching sessions and opt instead for short spurts. Although I do have a big 70,000 BTU Modine Hot Dawg heater suspended from the garage ceiling that heats the air up right quick, metal tools and parts take quite a bit longer to come up to temperature. And the garage is attached to the house, so it’s easy to wander in there and do 15–20 minutes at a time, then wander back in for a cup of coffee. If I’m putting something back together and find that the nylon on a nyloc fastener is worn out and no longer effective, or if I’m missing one washer, I’m perfectly content to break things up by running down to the hardware store and buy only the parts I need for the small segment of the project immediately in front of me. Sometimes I’ll make a hardware store run several times in the same day. And that’s perfectly fine with me. As long as there’s forward motion, I’m happy.

vintage cars in garage
During winter, the cars are packed in like sardines.

Back to the Lotus. I’d never rebuilt a double wishbone suspension front end before; most of my experience is on cars with MacPherson-style front ends. But it soon became clear that, while there are some things you can do without completely disassembling the front end, it was really kind of silly for me not to just take it all apart. The main issue is that the shocks/springs, ball joints, and trunnions are all sandwiched between the front and rear halves of the wishbones, so you need to split the wishbones to get any of these things out. Once you’ve done that, removing the wishbones just involves pulling them off their pivots. While you can wiggle the wishbones in place on their pivots to check for obvious play in the pressed-in metal and rubber bushings, in order to thoroughly inspect the bushings, you really need to pull the wishbones off.

vintage car suspension closeup
You can see here how the double wishbone configuration holds the shock/spring and the ball joint.

The first step was, unfortunately, trodding back down a path I’d walked in the spring—the brake calipers needed to come off. While it’s theoretically possible to suspend the calipers up under the wheel wells, they and their hoses would be in the way of other work. I hated to introduce air back into the lines I’d spent so much time bleeding back in May, but I minimized fluid loss by capping the unscrewed metal brake lines with little rubber caps purchased on Amazon. Similarly, I hated to have to pull the new rotors and wheel bearings off, but they have to be removed in order to unscrew the trunnions. So off came the calipers, rotors, and wheel bearings. I then used a puller to separate the ball joint and tie rod from the hub assembly and pulled the assembly off.

vintage car bare hub assembly
The hub assembly with the caliper, rotor, and wheel bearings removed.

The pivot on the top wishbone is simply a very long bolt. In order to withdraw it, though, you have to knock it backward through the car’s fiberglass body. To do that, you need to remove a rubber plug on the inner fender wall and peel back the carpet in the foot wells. I hated to do this latter step, as I expected the old brittle rug to shred as soon as I tugged on it, but fortunately it remained intact. And, in a surprising benefit, when I pulled back the carpet, it revealed a little shelf in the fiberglass body that was loaded with rodent detritus, the cause of a smell whose source had long been a vexing mystery. Being able to vacuum it out was an unexpected pleasure.

vintage car suspension parts closeup
The upper wishbone pivot bolt knocked partially back through the uncovered hole in the inner fender wall.

opened carpet lining in car
The pulled-back rug and, above it, the exposed Rodent Chamber of Horrors.

The lower pivot point isn’t a bolt but a double-threaded rod, so you don’t need to draw it through the body. However, clearance between the back half of the lower wishbone and the fiberglass body is tight enough that you can’t slide the rear wishbone off the rod until you pull the rod slightly forward. Unfortunately, after 40 years, the rod tends to be stuck in the metal tube it slides through. Lots of SiliKroil penetrating oil, combined with careful twisting with a Vise Grip, loosened it up.

rear wishbone spacing closeup
It’s difficult to see, but the curve of the fiberglass body prevents the rear wishbone from being slid straight off the pivot. Instead, the rod has to be drawn forward.

In fairly short order, I had the right side of the front end disassembled into shock and coil-over, four wishbones (forward and rearward for both the upper and lower), and the hub assembly with the upright link, axle, and trunnion still attached at the bottom.

disassembled vintage car suspension
The upper wishbones are still hanging from the pivot bolt, but everything else is out.

vintage car lower wishbone and hub parts
The removed lower wishbones flanking the hub assembly.

With the wishbones out, I inspected their bushings. Each bushing is a thin metal sleeve about an inch in diameter with a rubber insert and a metal dowel in the center, essentially a rubber sandwich pressed into a hole in the metal wishbone. Age and corrosion of dissimilar metals make them notoriously difficult to remove. They all appeared good; there was no apparent softening, degradation, cracking, or separation. I slid a metal rod through each bushing and used it as a lever to check for play and found none. Note that, last spring, when I examined the rear trailing arm bushings in the back of the car, they were obviously bad (soft and deteriorated due to oil contamination). These were nothing like that. The apparently intact front bushings may have been an unanticipated benefit of the Europa being a mid-engine car.

Last week, I mentioned the dynamic of “Do it once, do it right,” and how I generally bristle under this advice, feeling that unless someone wants to pay my repair bills (and, funny, they never do), there is no “right.” There’s just your budget and your own personal metric of where the line is that separates common “while I’m in here” from to fixing things that aren’t broken. Here I was, holding all four wishbones from one side of the car in my hand. There was nothing wrong with the bushings, at least nothing that I could see or feel, but was I really going to reinstall wishbones with 45-year-old bushings in them? It’d never be easier to replace them than right now. The bushings aren’t expensive, just $13 apiece. For just over a hundred bucks I could buy all eight, install them, check off “Replaced all wear and tear parts in the front end,” and be done with it.

I ordered the bushings.

People jury-rig the press-out and press-in of bushings like these using a threaded rod or a bench vise, but what you need to do it quickly and efficiently is a hydraulic press. Fortunately, I have access to one of these in a friend’s shop. I’d planned to fully rebuild the right side of the front end before moving onto the left, as that would provide me a template for reassembly if necessary, but because the bushings need to be pressed out, and because I needed to travel to use the hydraulic press, I wanted to do it all in one trip. So, I disassembled the left side of the front end, carefully labeled all eight wishbone pieces (they are each unique to their placement), gave each bushing a good soaking of SiliKroil, put them and the new bushings in a couple of bags, and took them to where the press was.

press removes bushings
Using the hydraulic press last spring to press out the bushings in the rear trailing arms.

On a quiet Sunday with no one else around, I carefully sized one socket to act as the pusher to press the bushing out from the top, and a larger one to support the wishbone from underneath and receive the pushed-out bushing. I’d used this same press several times over the years to re-bush suspension components, including the Lotus’ rear trailing arms just last spring, but this time, the bushings wouldn’t budge. I tried several of them. All I succeeded in doing was marring the wishbones where the supporting socket was holding them from underneath.

There’s an old saying: When an immovable object meets an irresistible force, something’s gotta give. Obviously, the bushings in the wishbones were immovable objects. The hydraulic press is damned close to an irresistible force. Unfortunately, the “something” that might give might not be the metal-on-metal interface of the bushing in the hole. It might be the wishbone where it’s supported by the socket. Lotus founder Colin Chapman’s well-known motto was “Simplify, then add lightness.” You’d never describe these wishbones as “beefy.” They’re thin stamped metal. I could easily imagine bending them if I went for it and just cranked down hard on the handle of the press.

I took all the parts back home and did some reading on Lotus forums. Many other folks had encountered the problem I was having with seize bushings. In general, for metal-stuck-on-metal contact, heat from a torch is your friend, as its use will both slightly expand the outer bushing hole as well as help to break the bond of corrosion between it at the sleeve, but when you put heat on a bushing containing rubber, it will ruin the rubber. At that point, you’re committed. You’re all in. There’s no going back. You have no choice but to completely remove the bushing by hook or by crook and press in a new one. I read posts where people described using a torch, still not being able to press the bushings out, burning out the rubber, pushing out the inner metal sleeve, and using a hacksaw to cut a thin notch in the outer sleeve to get it to release its death grip.

In my first book, Memoirs of a Hack Mechanic, I describe this “do I go all-in or not” dynamic and liken it to standing at the entrance to a cave, deciding whether or not to go in and slay the beast living inside. I say, “Look the beast in the face. If you’re not prepared to battle it to the death, back slowly out of the cave.” There’s no shame in doing this. It’s better than breaking old, fragile, expensive parts.

I looked at all the bushings again. I re-tested them with a rod, found nothing wrong with any of them, thought about how much I’d regret it if I began bending wishbones with the hydraulic press, and how unhappy I’d be if I had to spend multiple evenings hacksawing eight bushings that appeared to be in working order. And, with that, I backed slowly out of the cave, and left the wishbones and their original bushings alone.

Will I regret it? Well, if I put everything back together, drive the car a few hundred miles, and the front end becomes loose and I trace the cause to a bad bushing, of course I will. But I already put 700 miles on the car since its resurrection in the spring. I’d think that if an old bushing was going to separate, it probably would’ve already done so. To me, the risk of going all-in seemed much higher than the risk of leaving things alone. Note that, if I damaged a wishbone pressing out a bushing, new ones are no longer available—only new old stock, used, or refurbished ones, and a new tubular design with adjustable camber. Obviously, none of these are inexpensive.

When resurrecting or maintaining a vintage car on a budget and trying not to slide down the slippery slope toward the level of work associated instead with restoration, one makes these choices all the time. I’m very comfortable with this one. Others might choose differently, and that’s fine.

***  

Rob Siegel has been writing the column The Hack Mechanic™ for BMW CCA Roundel magazine for 33 years and is the author of five automotive books. His new book, Resurrecting Bertha: Buying back our wedding car after 26 years in storage, is available on Amazon, as are his other books, like Ran When Parked. You can order personally inscribed copies here.

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