Automania/Repair & Maintenance

AUTO QUESTIONS AND ANSWERS FOR WEEK 21 YEAR 2001

by Bob Hagin

Q. I have a 1992 Honda Civic with a 1.6 engine that has 193,000 miles and a 1998 Plymouth Neon Expresso with 62,000 miles. During hot weather while driving the Neon with the a/c on, the temperature rises. With the a/c off, the gauge returns to normal. I took it to the dealer and they ran some kind of test on the cooling system and couldn't find anything wrong, but the problem still surfaces occasionally. With the Honda, I also have a problem with overheating. I replaced the water pump, radiator and cap, thermostat (twice), head gasket, thermal fan switch, and upper radiator hose. I thought that my problem was solved but as recently as a couple of days ago while driving with the a/c on, the temperature rose slightly above the halfway point. I turned off the a/c and the gauge returned to normal, then briefly rose again and then again returned to normal. Did my mechanic miss something? K.H. Sacramento, CA

A. Evaluate the true operating temperatures of your cars. Have your mechanic temporarily install a non-electrical gauge that reads in degrees. Your cars may be operating within factory temperature limits. I worked on a car with a problem like your Honda. It had small cracks that weren't found until the totally-stripped and resurfaced head was pressure-tested on the bench. As for the Neon, it's well-known for having a marginal cooling system and could probably do well with a thicker radiator.

Q. I have a 1992 Ford Ranger with a 2.3-liter four-cylinder engine and an automatic transmission. Several months ago it began to leak oil. It wasn't much, just a few drops. I have gone to two Ford dealers who say it is the rear main seal, the oil pan gasket, the front main seal and the speedometer connection. I find this hard to believe because the truck has only 21,000 miles on it. One dealer wants $1085 for the repair and the other wants $1250. L.H. Auburn, WA

A. Better try a couple of independent shops and visually check the results for yourself while your Ford is on a lift. Have the oil and filter changed and a have a dye put in that can be seen under a ultraviolet light. After the engine and chassis has been thoroughly power-cleaned, the technician can lift the vehicle with the engine running and check the oil drips with the test lamp. This will pinpoint their locations and determine the fix. Changing to a different oil may help too. As you describe it, you've got fewer drips than places that they're supposed to be coming from.

Q. While waiting for a tire repair, I asked my mechanic about the big tank attached to his oil drain funnel. He said it was part of an oil reclamation system and boasted of no oil buying since its installation. Later I got to wondering about what quality, viscosity, etc. is produced from this device. While I like the conservation aspect of it, I'm leery of what might be called "generic" oil for my engine. A.D. Virginia Beach, VA

A. "Re-refined" oil is the end product of a long process involving used oils. These oils are first cleansed of their contaminants - such as dirt, water, fuel, and used additives - through vacuum distillation. The oil is then hydrotreated to remove any remaining chemicals. The process is very similar to what traditional oil refineries do to remove base oil from crude. Finally, the re-refined base oil is combined with a fresh additive package by the blender." This quote is from the Integrated Waste Management Board. There's only two re-refining plants in the country, so transporting it is tough. Unocal, Chevron and several others buy re-refined oil for blending and lots of fleets use it. Log onto www.re-refined.com. for more info. Unless the tank attached to the funnel at your mechanic's shop does all this, buy fresh oil.