Breaking Things to Fix Them
When Alloy+Grit decided to transform my personal Discovery project vehicle into the coveted prize of a reader sweepstakes, the main priority was to enhance its off-road capabilities without sacrificing any of its family-friendly qualities. I’m a big fan of having a vehicle that I can drive every day (for the usual chores assigned to a motorized dad) and then pack up for a weekend away. And while I enjoy getting out to club trail rides and off-road weekends, I’m more of a traveler than a wheeler.
Safety and reliability, though, will be no less important for this build than achieving greater functionality. And the work has already started. As luck or misfortune would have it, just before we started digging into the fun stuff, a weekend in the woods reminded us we should start with a detailed assessment of, well, everything under the Discovery’s skin as well as some much-needed routine maintenance. Bouncing through the Poconos on unimproved trails, it seems, is an excellent way to deform the rear suspension’s Watt’s link bushings as well as untie the front tie rod ends (not a completely accurate description of the problem).
Nothing broke on the trail, though. In fact, it was a couple days later before I noticed a clunking sound from the rear suspension when backing up on a gravel driveway. The Disco still tracked straight, but any light lateral movement served an aural reminder that something back there would need to be addressed before any modifications could be installed.
The first step was fitting a slew of new suspension bushings from British parts supplier Bearmach, setting a solid foundation for the next phase, a suspension lift. The plan is to install two-inch taller springs in the front and two-inch lift mounts in the rear (so that we can retain the factory rear air springs), along with a set of heavy-duty shock absorbers.
Okay, I hear the screaming: “Why in the name of coiled steel would you keep the air springs?” A few reasons. First, I actually prefer the way the Disco rides on airbags. I’ve owned a coil-sprung Disco II as well, and the air springs ride better. Second, both the rear bags were replaced recently with new components from Arnott, and because they were replaced before their slow leaks became gushers, the pump was never overburdened and thus continues to perform reliably.
Finally, I really like the functionality of an adjustable suspension, especially on a vehicle that serves multiple duty. When I filled it with 40 boxes of magazines (roughly 1,500 pounds) to drive from upstate New York to Philadelphia, its back end went from a tail-dragger to proud and perky in just a couple minutes. And on the same trip that wrecked my suspension bushings, I used the air springs’ lift setting to gain a couple extra inches of departure clearance to cross a log without leaving the rear bumper in the woods. Land Rover’s engineers dreamed bigger than a mere fixed-height suspension, and I’m not willing to regress.
Another major system demanding immediate attention was the brake system —not just pads and rotors — the whole system. To start this tale of breaking brakes, my Discovery, like so many others, has graced me with the presence of the “Three Amigos,” the three warning lights – ABS, Traction Control, and Hill Descent Control – that, like a bellicose mariachi band, descend upon you unexpectedly and refuse to leave until you pay up. I’ve been ignoring them under the assumption that the likely culprit is the ABS system’s shuttle valve switch, which according to some sources is responsible for about 95 percent of Three Amigos appearances. The other five percent come from a failed wheel speed sensor or ABS modulator or simply from a wiring fault.
Regardless, the presence of the Amigos means both traction control and hill descent control are useless, even if ABS still works, which it often does not. It also disables the cruise control. All of these features are nice to have in a 5,000-pound truck, so I drove it to British 4×4 Center, a Land Rover specialist near Hershey, Pennsylvania, for a proper assessment. Shop owner Trevor Griffiths scanned the truck to discover that it was indeed the shuttle valve switch, which meant a fairly easy replacement that doesn’t necessarily require opening up the brake’s hydraulics and thus having to bleed the system.
Bleeding, though, was the smallest of concerns. I had already planned to replace the leaking master cylinder as well as overhaul the calipers and install fresh pads and rotors. The master cylinder was first as a matter of necessity — the Disco failed the state’s annual safety inspection on the basis of a weeping unit, but the job took only fifteen minutes or so outside of the actual bleeding.
Now that the Disco was again road-legal, the next step in the overhaul was preemptive maintenance on the crusty, aging calipers. The right rear rotor had developed a pulsing under load, possibly because one of the guide pins on that caliper had become corroded and was likely seizing on occasion. Having parted out a fairly clean Discovery a couple years ago, I happened to have a spare set of brake calipers hanging around. So while the original set was still on the car and essentially functional, I took the opportunity to overhaul the spare set before fitting them.
Disassembling the calipers to the bare castings, I media-blasted the external cast iron to a clean surface, careful to block off the piston chambers and bleed holes. Once stripped, I chemically cleaned all the calipers to remove any residual oils. Next I heated them to 450 degrees F to off-gas any oils trapped in the metal. Once cooled, I repeated the chemical and heat treatments for good measure.
Why all the fuss for calipers? While I certainly could have reassembled the units with fresh seals and hardware, all the effort to rejuvenate them would have been wasted in a matter of months. I had decided in advance that I wanted to powder-coat the calipers for a more lasting appearance.
Using Eastwood Company’s dual-voltage powder-coat gun and benchtop curing oven, I shot the bare calipers with a unique copper vein coating, resembling the classic industrial Hammerite finish. This choice adds a little visual pop behind the wheel without, like red or yellow, looking out of place, and it doesn’t get lost like black or silver.
With new seals and guide pins installed, the refreshed calipers were mounted to the Discovery, along with fresh rotors all around and new Hawk high-performance brake pads. Before bleeding the system yet again, I also replaced the aging rubber brake hoses with new braided stainless-wrapped nylon hoses, an extra two inches in length in preparation for the eventual suspension lift.
Now that the steering is once again tight, the axles are securely located, and the brakes are rock-solid, we feel comfortable moving on to our upgrades. Next up is suspension, followed by tires. After that we’ll start outfitting it for life outside of civilization. Follow the progress on ProjectD2.net where you can also enter for your chance to win the completed project at Overland Expo East on October 1, 2017.