Help! My Truck Won’t Start!
So there we were, hundreds of miles from home, pulling a trailer, with a truck that wouldn’t start. Geez…aren’t 12-valves supposed to be reliable!? As it turns out, it was no big deal, but a non-starting truck can definitely give you that sinking feeling. We’ll explain.
One of the more common problems on virtually all ‘94-’98 Dodges, as well as some generators and tractors, revolves around the P7100 injection pump. While the pumps themselves are extremely reliable and hardly ever fail, the shutoff solenoid that is mounted to the pump fails often. Our ‘95 project truck dubbed the Green Monster already had its solenoid replaced somewhere down the line, but it still failed yet again (probably because it was a Chinese-made knockoff verson). The shutoff solenoid activates a governor lever that allows fuel to flow into the pump, which allows the engine to start, but also to stop, because cutting off the fuel is how virtually all diesels are stopped from running.
So our solenoid was bad, but fortunately we weren’t dead in the water. Thankfully, even if your solenoid is weak, you can still almost always start the truck by turning the key on, walking around underneath the hood, and then manually moving the governor lever back towards the firewall of the truck. It’s a pain (and something that would be horrible in traffic) but at least that will get your truck going down the road again.
Still, we weren’t excited about the prospect of hopping out and opening the hood every time we needed to start the truck, so we contact our buddy Rex Gully who owns Allied Diesel in Windsor, California. Like us, Rex is another 12-valve aficionado, and owns a fleet of them, including a 10-second race truck. Gully recommended using one of the shutoff solenoids from LarryB’s Diesel Parts. Larry has been in the business for years, and has all sorts of electrical parts for worn out Cummins engines, including starters, relays, cables, and yes…shutoff solenoids.
With Rex manning the wrenches, we were walked through the fairly straightforward process of replacing the shutoff solenoid. It’s a task your average shadetree mechanic can perform, as only basic hand tools are required and there’s only a couple steps where things can go wrong. After around a half hour of installation and adjustment, we were back on the road again, and now could truck happily down the road without worrying about the next time we turned off our Cummins engine.
Allied Diesel Performance
LarryB’s Diesel Parts