More annoying than that, however, is the overheating. More than likely this is related to this problem, though I'm not entirely sure. When laden and pulling a grade, however slight, the temperature creeps up quickly in a truck. This is ordinary and the engine fan kicks in at 210 degrees and knocks it back to down to 200 before turning back off. In this heat however, on really long grades, even the slightest of them, I've been experiencing problems with it climbing over the 220 mark, which results in the computer shutting the engine down. I've learned over the course of this summer how to avoid this: I have to keep the RPMs above 1500 so that the fan turns fast enough to cool the radiator sufficiently. This isn't difficult to do, just annoying. Sometimes you have to slow down and grab a lower gear just to keep the RPMs there.
Since I've figured this out, my previous two students both had a good deal of experience with road tractors and making them understand this principle wasn't difficult. With Tom, however, it's been more difficult impressing upon him the importance of this. He learned this lesson the hard way the other night as we were driving into Memphis. It was a long, gradual grade; virtually flat to the eye but Sally sure knew it. The "high coolant temp" warning was given and I instructed Tom to get onto the shoulder as quickly as possible. In times past when it's happened to me, getting off the road and letting the engine idle quickly enough will sometimes avert disaster.
Okay disaster is a strong word. Pain in the ass might be more appropriate, only this time it was disastrous.
The truck shutdown from the high temperature as expected. Ordinarily, I fix this problem by CAREFULLY venting the coolant reservoir, letting the hot vapor escape then refilling with some fresh coolant. Apparently I wasn't careful enough and the cap blew off the reservoir as the pressure inside sought its way out. I was greeted with a blast of hot coolant to the face. I was standing on top of the motor when this happened and I immediately turned and jumped for the ground before I got myself completely scalded by the green geyser spewing from my motor.
Thankfully I wasn't hurt, from the coolant or the jump. The sudden pressure release had resulted in a complete loss of coolant. I had four gallons of coolant on-board with me and began pouring it into the reservoir, watching it all disappear down into the motor. There simply wasn't going to be enough to run it. What's worse was that the reservoir cap was nowhere to be found. We tried looking up and down the highway, in the nooks and crannies of the motor, and the ground beneath... it was gone. I'm guessing it was ejected into the corn field and lost. So even if I had enough coolant, I had no way to keep it in.
First I called the breakdown department of my company. After being on hold for over twenty minutes I sent a Qualcom message to them. After no response for 15-20 minutes that route, I decided to take matters into my own hands. I called welfy and got her to run some Google searches for a Freightliner dealer in the Memphis area. Armed with phone numbers I placed calls until I got myself hooked-up with an area towing/repair service. I employed them to pick me up a cap from the dealer and to bring me copious gallons of antifreeze and water. The entire ordeal took 3-4 hours and we were finally back on the road. Ever since then, Tom has been more vigilant in monitoring the temperature guage on grades, making sure Sally keeps cool and it hasn't been an issue again.
Otherwise, it's been a great week. I've covered nearly 5,000 miles in the past seven days. It's much needed after the way last week went.