Trasborg's Kaiser M715 - Universal Jeep Cooling

Some people will tell you that a high-flow water pump and a high-flow thermostat will make the water flow too fast through the radiator and not cool off enough. We aren't buying that. At every corner, we've put in a high-flow pump and these Robertshaw Thermostats, which we got from Flow Kooler. The high-flow thermostats not only flow better, but the action of the valve opening is better-in 10 years, we've yet to have one stick.

We installed a pair of Flex-a-Lite universal 16-inch fans. They turned out to be too large in diameter, and we wanted an automatic controller, so we installed Flex-a-Lite's kit made for Chevys that included an automatic fan controller (PN295). Regardless of the part number we used, measure your available space carefully and choose the highest-flowing fan that fits the space.

If you install electric fans, make sure they're close to the radiator. Again, not wanting to damage the radiator, we had put Ford Taurus fans on a custom tube mount that ended up spacing the fan blades almost 2 inches from the back of the radiator. This is no good for the same reason not having a fan shroud on a mechanical fan is no good. It will simply draw air from around the radiator rather than through it.

Timing: We timed this engine by ear initially. It came to our attention that putting too much timing into the engine, either initially or total timing, could cause overheating. We got an adjustable timing light from Summit Racing and checked it. While a regular light could tell us what the initial timing was, the only way to figure out if we needed different springs or weights in the distributor was to check total timing with the Summit timing light. Turns out, our distributor was OK as it was delivered out of the box.

If you're still running an engine-driven fan, make sure the blades are in decent shape, but more importantly, if you have a clutch, make sure it works. Run the engine up to operating temperature by driving it around for a while, then shut it off. The clutch should be engaged at that point and not allow you to turn the fan, or at least provide resistance to you turning it. Most importantly, make sure your fan shroud is in good shape.

At one point, when it was hot enough to fry eggs on the power-steering pump, the truck got a B&M Super Cooler for the steering fluid that went in front of the radiator. If your cooling system is marginal, don't put stuff in front of the radiator. The Super Cooler now resides under the bed.