For instance, I drove my MG TD to work yesterday and when I pulled into the parking lot I noticed the tach wasn’t working. Opened the hood and, sure enough, the fan belt had flown off. Half of it had turned into a “string” that was wound around the fan hub. The rest was just flopping. I had an old emergency belt in the underhood tool box, but it was a tight fit, so I had to remove the generator. When I did, I noticed the pulley was loose. The Whitworth socket wrenches I had in the tool box were too “meaty” to get where they had to in order to tighten the nut all the way, but I got it tight enough to drive home.
Thursday is work-on-the-car night and my mechanic friend Vince Sauberlich was there when I got home. We took off the generator and pulley again. “Do you see that brown stuff that looks like dust on the pulley?” Vince asked. “That tells me the nut was working loose for awhile; as it did, it ground the rust off the threaded end of starter armature and deposited on the pulley.”
Vince thinks the armature is too short. “I’ll bet the last person who rebuilt the starter didn’t have just the right armature,” Vince guessed. “So, he used a similar one that was just a little too short. If I’m right, as you start driving the car again, you’ll notice new brown dust on the pulley. If that happens, you’ll know the nut is working itself loose again. In that case, I’d replace the starter.”
Like I said, there’s a reason to do the job right the first time. The car will work better for you and the next owner will know that the parts on the car are correct for it.