Question: I have a 1984 Ford Ranger pickup with a four-cylinder engine. The engine gets unusually hot on a warm day or in stop-and-go traffic. The dealer says it's normal and not to worry about it unless the temperature gauge goes into the red zone. Can you give me any advice on this problem?--S.R.
Answer: The cooling systems on a lot of newer cars have less reserve cooling capacity than cars did years ago. A hot day or a full load may cause the temperature of the engine to increase sooner than it would have on a bigger cooling system.
Modern engines are packed more densely into their compartments and rely on very precise controls to maintain temperature. They usually have electric fans that don't switch on until a preset temperature is reached, whereas a few years ago engines had fans that continuously blew cool air over the engine. In addition, the grills on new cars are getting smaller for styling reasons, which restricts the amount of air that blows into the engine compartment while the car is in motion.
As a result, it is somewhat more common for the temperature needle to creep over to the red zone. Unless the gauge is in the red zone or almost always near it, you're pretty safe.
Q: I own a 1973 Pontiac Grand Prix with 89,000 miles on it. You recently advised a reader that whining at various speeds may have been caused by worn wheel bearings. I have a similar problem and had the bearings replaced but the noise persists. Any further suggestions?--M.L.
A: You should determine the circumstances in which the noise occurs. Does the noise continue unchanged if the car is put in neutral and allowed to coast? If so, that might eliminate the engine as a source of the noise. Does the speed of the engine affect the pitch of the noise? In that case, you could eliminate everything in the drive train past the clutch.
Usually, a whining noise is caused when either a bearing or a bushing begins to wear out or lose lubrication. Wheel bearings often whine as they wear out. Universal joints on a drive shaft sometimes make those noises. Alternators and water pumps on the engine can whine as well. Your mechanic should first isolate the general area that is producing the noise, and then try to find the defect.
Q: How can I break loose the water drain plugs on my engine block? I want to drain and flush the system. The car is a 1983 Chevy Malibu with a V-6 engine.--R.L.
A: Engine drain plugs often rust in place, and freeing a stuck plug can ruin a Saturday afternoon. If all you want to do is flush your engine, I suggest you install a back-flush kit, available at small cost at most auto-parts stores.
The kit contains a fitting that you install by cutting your rubber heater hose. You can then easily back flush the cooling system without bothering to remove the drain plugs. Hook your garden hose to the fitting to clean out the coolant inside the engine block.
But if you still need to free the engine drain plug, you should start with some penetrating oil and allow it to work for several hours. That probably won't work, so you'll need to take more drastic action. A propane torch works well in freeing rusted threads. Heat up the area around the plug for several minutes and then try your wrench. Don't strip the head or it will have to be professionally drilled.
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.