Our Project Bronco Avoids Overheating Disaster Thanks To A Flex-A-Lite Radiator/Fan Combo
There's really no simpler way to say it: engines get really hot when the throttle pedal is always mashed to the floor. Add larger tires and a driving surface that will create extra resistance (like deep sand or mud) to the mix, and it's pretty likely that a truck's stock radiator just won't be able to cut the mustard. When we drive The Juice, our project Bronco on 37-inch tires, we pretty much always have the go-pedal pushed into the floorboards and we've watched the temp gauge with some concern as it routinely spiked, telling us our engine was well beyond a normal, healthy operating temperature. It was time to upgrade the radiator, so we called Jeff's Bronco Graveyard and ordered a Flex-a-Lite aluminum unit with two big electric fans.
We were especially excited about the electric fans for a couple of reasons. For one, electric fans can be activated by a thermostatic switch and only engage when the engine coolant reaches a certain temperature. In this case, those fans aren't always running (like a stock fan), and this can help the engine warm up faster. Then, once the engine has warmed, the dual fans (mounted on the radiator itself) are automatically switched on and cool with much greater efficiency than the big, bulky stock fan, which was mounted back in the engine's pulley system. Ridding ourselves of that big stock fan was the other big plus-spinning fan blades are just dangerous. Our fan cowl had fallen off long ago and the exposed metal OEM fan could have easily taken off a finger. The twin high-impact plastic Flex-a-Lite fans are self-contained in their own cowls, and don't protrude past them.
And yeah, the radiator itself is pretty awesome too. It's a dual-row aluminum unit, 3.75 inches thick, and features internal fins to absorb heat more quickly, and then radiate it through external fins on its body. The Flex-a-Lite unit looked especially burly when we pulled out our stock radiator and compared the two-it was like seeing a heavyweight prizefighter standing next to a horse jockey. Not that we have anything against horse jockeys....
The install itself didn't involve anything too tricky, except for the fact that the mounting points on the Flex-a-Lite unit were spaced a little narrower than the OEM radiator. This could have been remedied with metal plate brackets bolted together, but then we found out that Link Motorsports, a custom off-road shop with a ton of race-truck building experience, is located right down the street from our office. We drove the Bronco over to see them, and they welded up some small tabs that allowed the Flex-a-Lite radiator to slip right into the stock mounts. Soon, the Bronco was running as cool as a cucumber. Check out the photos to see what was involved in the installation.
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