Automania/Repair & Maintenance

AUTO QUESTIONS AND ANSWERS FOR 1996 WEEK 11

by Bob Hagin

Q. I have a 1995 Buick LeSabre with a 3.8 liter V6 engine. When the engine is idling, there is a whining or humming sound coming from the engine compartment. If I step in the accelerator or actuate a power button for a window or to move the seat, the noise will stop. My service department has changed the alternator and retorqued the alternator mounting bolts but the engine still has the noise. The mechanics apparently don't know where the noise is coming from.
C.H. Ft. Wayne, IN

A. It shouldn't be too difficult to determine where the noise is coming from and I'd be surprised if your mechanics haven't pinpointed it to the area of the alternator since they've replaced it. A quick test would be to use a mechanic's stethoscope. The probe is put on the various ancillary units that are driven by the engine drive belts while the engine was running and the noise shows up right away. Sometimes a minor, engine-speed sensitive noise will crop up if the pulleys on the devices that are driven by the belts are either "skewed" or not in perfect alignment. You car is still new enough that the factory should be interested in the problem since yours is probably not the only '95 LeSabre with the problem. Your owner's manual should have an 800 "hotline" number to contact and your dealer can get you lined up with the factory field representative that covers your area. The problem with ignoring a small noise, minor though it may seem, is that it could get worse after the car is out of warranty and leave you with a repair bill.

Q. The engine in my '77 Southwind RV is a Dodge 440 cubic inch V8. I got hit on the front bumper and had to replace the radiator. Since then it overheats and I've replaced the 195 degree thermostat three times trying to keep the temperature down. It doesn't heat up until it reaches 50 to 60 MPH and it doesn't have water in the oil which would indicate a blown head gasket. I can't hear any noise coming from the water pump so I don't think that it is the problem. Now the engine won't run because the carburetor is warped but I plan to replace the it with an all-metal Holly four-barrel. The engine backfired and destroyed the original.
R.B. Deadwood, OR

A. Once you get your RV going again, check the temperature-controlled clutch in the cooling fan. Sometimes they pack up and won't engage to pull air through the radiator. It may have been damaged when your Southwind got its bumper tagged. Also check out the temperature gauge and sending units since they may be giving you a false reading. Be careful when you replace that plastic Thermoquad with a Holly. In some states, the replacement has to be pre-approved by the state in order to be smog-legal.

Q. I don't have a problem but my daughter drives a 1993 Toyota Tercel with 33,000 miles on it. I am concerned about the timing belt problem that I've heard about. I'm told that it breaks prematurely and strands the driver. How can a corporation produce millions of cars without having any problems and then have one particular car that has a problem like this? I would be scared to death to drive an '86 Celica that has a timing belt problem. L.C. Yicaipa, CA

A. Using a fiberglass/plastic "toothed" belt to drive the valve mechanism is pretty much standard procedure today and I think the reason is economic. It's lots cheaper than using a roller chain that needs to be enclosed in the engine and lubricated by the engine oiling system. I'm not enough of an engineer to be able to second-guess the Toyota engine designers but I suspect that it may be the amount of "load" that the system puts on the belt. This can vary from design to design but if it's any consolation, I've had to replace lots of cam-drive belts on Ford four-cylinder engines.