HOT ROD to the Rescue
THE RESCUE SO FAR
Tevete (“T”) Usumalii and his 1998 Ford Bronco have really been put through the wringer. It all started when a missing
25¢ oil-galley plug cost him his 349ci stroker small-block Ford engine. L&R Engines fixed the short-block (June 2018 issue). In the July 2018 issue, Mark Sanchez at Advanced Engineering West (AEW) assembled the engine top-end only to discover valvetrain geometry and lifter problems, a wrong distributor gear, and serious issues with the fuel-supply system. Finally home-free? Not on your life! The engine front accessory drives, fuel tank gauge, and custom instrument panel implementation were still screwed up. We’ll fix them this month, then put the Bronco on Westech Performance’s chassis dyno for a quick tune and test.
THE BELTDRIVE FIX
The original builder had butchered the front serpentine drive system. “There wasn’t
“I’m so grateful! I’m overjoyed to finally see my Bronco up and running.” — Tevete Usumalii, Owner
enough belt-wrap around the water pump and crank pulleys,” Sanchez explains. “I hold to the factory spec: The belt needs to contact ¾ of the pulley grooves’ surface area. I was able to round up the missing parts from the local Pick-A-Part yard, eBay, and AutoZone. The air-conditioning system had been removed, so we also added a Dorman A/C compressor bypass kit to perfect the setup.”
An inadequately sized electric fan had been installed in place of the Bronco’s original mechanical fan setup. Sanchez found and installed a kick-ass 1994 F-150/F-250 pickup truck 302/351W seven-blade mechanical fan, clutch, and shroud. Also needed was a heater hose fitting to accept the engine coolant temp sensor. Lastly, Sanchez replaced the water pump: “It was full of silicone. At this point I didn’t trust anything on or near this truck.”
THE DASH FIX
The original builder tried to fab a custom dash with individual AutoMeter gauges. But they were partially blocked by the steering wheel. Worse, they weren’t working and the original instrument panel warning lights and turn-signal indicators had gone MIA.
Unbolting the dash panel revealed the major wiring issue. On a stock Bronco dash, the wiring plugs into a common circuit board that distributes power to the various gauges and warning lights. But aftermarket AutoMeter gauges must be hard-wired— which the original builder lamely tried to do with so-called self-stripping T-taps that invariably cause voltage drops.
The budget approach would be cleaning up the existing wiring, leaving the original gauges and their layout as-is. AutoMeter offers a wire and connector harness for wiring up most of its individual gauges that makes for a clean, idiot-proof installation that eliminates any possibility of cross-connection. As for the warning, message, and turn-signal lights, AutoMeter’s standard bulb and socket-withpigtail package just happens to screw right into the original factory dash holes.
But that doesn’t solve the visibility problem. The premium fix as implemented by Sanchez on the Bronco was to build a new custom instrument panel using AutoMeter’s trick combo gauges: one dual speedo/tach gauge plus one quad combo that displays coolant temperature, oil pressure, voltmeter, and fuel
level. These two gauges centrally mount in a new Sanchez-fabbed dash panel, right in the driver’s line of vision. The panel itself was cut and shaped from ABS plastic sheet. ABS sheet is sold through art and hobby-shop retailers, custom stereo shops, plastic distributors, and even Amazon.com. Cut it to size with a scribe tool and hole cutters.
Next, Sanchez built a quick- connect custom harness for the two combos. At the gauge end, he used AutoMeter’s available eight-cavity, Molex-style gauge connectors and terminals instead of error-prone individual blade-and-spade hookups.
At the other end, four- and eight-pin Ford OE Wedgelock connectors hookup to the main factory harness. You can find the four-pin mating connector bodies used on many Ford O₂ sensors, but scoring both halves of the eight-pin variants is dicey (Sanchez has used ones for sale). The harness also uses correct Ford factory colors and striping, allowing any Ford tech to troubleshoot the wiring, and
(if the original wiring wasn’t butchered) even bolt the original stock panel and its circuit board back into place.
THE FUEL LEVEL FIX
After the wire-up, the fuel level gauge worked but was inaccurate. Like many aftermarket units, AutoMeter’s fuel gauge is designed to work with a sender having a 240- to 33-ohm fullto-empty resistance range. A 1987-and-later Ford in-tank sending unit
“I call T-taps ‘vampire splices’ because they suck the life out of the car’s electrical system.” — Mark Sanchez/AEW
01] Tuning the MegaSquirt port EFI system on Westech Performance’s chassis dyno: The toughest part was perfecting morning cold-start performance. It could only be tweaked once a day, after the vehicle sat overnight. Preventing morning in-gear stalls required adding more air via the IAC motor plus pulling some fuel out of the ECU’s cold-start enrichment table.
[ The gauges in the existing custom dash panel didn’t work, plus they weren’t fully visible.
The instrument panel wiring was totally borked.
[ T wanted a powerful, off-road fun truck. We ended up fixing the engine, the fuel system, the instrument panel, and the front drives.
[ Slipshod mechanics had nearly turned “T” Usumalii’s 1988 Ford Bronco into a dead horse. But after the latest fixes, he’s overjoyed!
02–03] The “street racer” installer never bothered make the serpentinedrive system work efficiently without an A/C compressor ( 02). Insufficient “wrap” around the water-pump pulley caused belt slip. “Ford specs says the belt must contact ¾ of the pulley groove’s surface area,” Sanchez explains. He scored a complete 1988 Bronco front-drive setup from the local Pick-A-Part, but without the A/C compressor, a Dorman compressor bypass kit was also needed ( 03, arrow). AutoZone supplied a new belt and water pump, while the 1987–1992 Bronco tensioner is new from Jeff’s Bronco Graveyard. “Never reuse a high-mileage tensioner,” Sanchez insists.
04] Sanchez put in the sevenblade mechanical fan, fan clutch and shroud used on 1994 F-150/F-250 302/351W-powered pickups with air conditioning.
“It’s the most efficient cooling package Ford ever offered, with the heaviest and tightest clutch.” The fan and shroud were wrecking yard parts, but the clutch is new. Used clutches are sketchy, in Sanchez’s opinion.
[ No more bucking Bronco; fixed at last, it now gallops happily down the road. Says T, “I can’t wait to take it home and show it to my family!”
[ AEW’s Mark Sanchez fixed the gauges, wiring, and front drives. Westech’s Ismael Candia ( shown) and Eric Rhee tuned MegaSquirt’s EFI.
[ Sanchez built a new ABS dash panel to hold AutoMeter’s trick combo gauges that are easily visible from the driver seat.
BEST 07–09] The sloppy builder used quick and dirty push-together splice clips that clip over and through existing wires ( 07). They’re death on 12-volt circuits, causing resistance resulting in a voltage drop. The budget solution: Wire-in the existing individual AutoMeter gauges using its PN 2198 wire harness ( 08) that support an individual speedo, a tach, and up to four more full-sweep electrical or LED gauges. The high-end method: Sanchez’s custom wiring harness with “plug-and-play” AutoMeter Molex and Ford multipin Wedgelock connectors ( 09). AutoMeter bulbs and sockets ( arrows) restored the factory warning lights and turn signal functionality.
10–12] Correct Ford color-coded and striped wires ( 10) connect to the gauges. Del Mar Wire will stripe 100 feet of any single color it sells for a nominal extra fee; most other wire outfits require 1,000 feet per color and stripe. Ford connector bodies are hard to find, but its 0.062-inch diameter pin-and-socket Wedgelock terminals are widely available ( 11), and you can install them on the wires using generic crimpers for typical factory-style open-barrel terminals ( 12).
06 05–06] The Bronco’s OE dash had been replaced by a custom setup with individual AutoMeter gauges. But they didn’t work, weren’t fully visible when installed ( 05, A), and accessing the speedometer adjustment knob on the new unit was blocked ( B). Sanchez solved the visibility issues with AutoMeter combo gauges—a dual speedo/tach setup and a quad coolant temp/oil pressure/voltmeter/fuel level unit—that mount in a new panel built with 0.118-inch-thick ABS plastic sheet ( 06).