Question - I am driving a 1985 Chevy Celebrity with approximately 39,000 miles. There is a loud clicking sound emanating from the left front wheel. The click is apparent at any speed, but it sounds faster at higher speeds. Three different mechanics have checked this wheel for causes and came up with nothing. Can you explain this? - Tom
RAY: Sure, I can. What I can't explain is why these guys didn't at least try to sell you something anyway. Not even a new pair of fuzzy dice! We're going to have to drum these guys out of the Fraternal Order of Boat-Owning Mechanics.
TOM: My guess is that you have a warped disc rotor, Tom. The disc rotor - which looks like an over-sized audio CD - spins along with the wheel. And the brake pads sit on either side of the disc rotor, just a nose hair away from it. That way, when you step on the brakes, the pads squeeze the rotor immediately, and there's no delay in slowing the car.
RAY: And if that rotor is warped, even a little bit, every time the high point in the rotor comes around, it pushes the brake pads back against the caliper. And that's what makes the clicking sound.
TOM: Have your mechanic check the discs for "run out" with his dial indicator, Tom. If they show signs of warping, I'd fix or replace them. Aside from that annoying click, warped discs make the car brake less effectively. And as they get worse, you may also notice that your brake pedal pulses when you slow down from highway speeds - although with only 39,000 miles in 11 years, I suspect highway driving isn't one of your big pastimes. Good luck, Tom.
Question - I change the oil on our 1988 and 1991 Ford Tempos. When I start the engine right after an oil change, the oil light stays on for two or three seconds until the oil filter fills up. The filter is almost horizontal on the engine when installed and will hold very little oil. So I can't fill it up ahead of time. Any suggestions on how to minimize those two or three seconds of extra wear and tear before the oil pumps through the system? I cringe until that oil light goes off. - John
RAY: I always see my brother cringe when he starts his car, too, John. But I'm not sure if he's cringing because he's afraid it won't start or because he's afraid it will!
TOM: Actually, you're right to worry a little bit, John. Some damage IS done during those few seconds without oil pressure. That's why on cars where the oil filter hangs down, we do recommend filling the filter with oil before installing it. That way, full pressure is reached almost right away.
RAY: In cases where that's not possible, I'd suggest two things. First, whatever you do, don't rev the engine as soon as you start it. That would certainly hasten the demise of these two world-class automobiles.
TOM: And if you really want to be good to these cars, you can disconnect the coil wire or the wiring harness that goes to the electronic ignition. Without those, the car will crank, but it won't start. And while it's cranking, the oil pump will do its job. So you'll be filling up the filter and building up oil pressure while the engine is turning very slowly - at, say, 100 rpm, vs. 1,000-2,000 rpm once it actually starts.
RAY: And even my brother knows enough math to understand that running the engine on low oil pressure at 100 rpm for two seconds does less damage than running it at 1,000 rpm for two seconds.
TOM: After you've cranked it for a few seconds, you can hook the ignition back in, and start it up. And you shouldn't see the oil light at all. The only cringing will be from the realization that you've just added to the number of miles you'll have to spend driving that Tempo!
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