Question: I have heard two conflicting things about clutch wear. One person says when waiting at a light, a driver should put the transmission in neutral and release the clutch. The other says the clutch should remain disengaged. Which causes less wear?--K.S.
Answer: The wear on the clutch is only one aspect of whether you decide to shift into neutral at a stoplight, because safety and convenience also are considerations.
From a purely technical standpoint, keeping the clutch disengaged while you wait for a long stoplight causes a small amount of wear on the clutch.
Most manual clutches work with two friction plates that rub against each other to transfer power. Disengaging the clutch pulls the plates apart, but the clutch plates are never perfectly disengaged.
In addition, keeping your foot on the clutch pedal will maintain tension on the clutch cable, which most manual clutch systems now use to link the pedal to the clutch.
But you have to ask yourself whether it's worth all the trouble to shift into neutral and then again into first gear at every stoplight.
If you wait for the light to turn green and then rush to pop the clutch into first gear, you will probably cause far more stress and wear on the clutch than you saved by shifting into neutral. A clutch on a good car can easily last more than 80,000 miles if you treat it properly.
You should be ready to move with traffic when the light turns green. If you're shifting into neutral so you can fiddle around inside the car, you're asking for trouble.
Q: The air conditioning on my 1977 Chevrolet Caprice will not work at all when it is switched to the maximum setting. It will, however, operate on the other two settings, normal and bi-level. Also, when set on normal, the fan will not operate when flipped to high. But it will work on all the other speeds. What's wrong?--E.L.
A: Because the air-condition system works some of the time, you can eliminate any problems with the refrigeration system and concentrate on the electrical system.
You say the air conditioning doesn't work at all on the maximum setting. In that setting, the fan is automatically put on high speed. You also indicate that on the normal setting, the fan doesn't work on high speed.
I think your problem is likely to be with the electrical components that control the fan speed. The fan motor is controlled by a resistor and coil inside the housing, which is accessed inside the hood. It's located on top of the cowl at the rear of the engine compartment, inside a diamond-shape shroud. The resistor is probably burned out.
Q: I have a 1982 Honda Civic 1300FE with a manual shift. For the past two months, I've been having trouble shifting the car into first gear and reverse. It seems to be getting worse. When I come to a stop and attempt to shift into first, it won't go unless I force it. It also does the same thing in reverse, except that the transmission makes a loud grinding noise when I force it. Am I ruining my car by driving it this way?--J.C.
A: I suggest you get your car into the shop right away for a clutch adjustment. I suspect that your clutch is not fully disengaging. You can check for that by seeing if the clutch-pedal engagement point is almost at the floor. You're certainly putting a lot of stress on both the transmission and the clutch.
Ralph Vartabedian cannot answer mail personally but will respond in this column to automotive questions of general interest. Do not telephone. Write to Your Wheels, You section, The Times, Times Mirror Square, Los Angeles 90053.