Automania/Repair & Maintenance

AUTO QUESTIONS AND ANSWERS FOR WEEK 42

by Bob Hagin

Q. I have a 1991 Jeep Wrangler with a 4.0 liter fuel-injected inline six with 136,000 miles on the odometer. I had the slave cylinder on the clutch operating mechanism replace about 20,000 miles ago. Six months ago I started losing pressure in the clutch hydraulic system. Its performance can be returned by a quick bleed which was normally good for about a week. This time period has been shortened to the point where I must now bleed the clutch every two days. There is no loss of fluid or leaks apparent in the system. I assume that air is entering the system somewhere and I have tightened all visible systems as well as replaced the master cylinder cap seal. M.S. Vallejo, CA

A. I've worked on cars that had the same puzzling problem but not for a long time. The cars were British and used the same hydraulic clutch operation as your Jeep. They would lose their clutch operating action but didn't show any signs of leakage. The action returned when I bled a small amount of air from the slave cylinder. My theory on the problem was that air was being sucked in through the primary seal of the master cylinder when the clutch pedal was released and pressurized fluid was pulled back. The problem would disappear when I'd rebuild both the master and slave cylinders (new units weren't readily available) and do a thorough flush of the system with the bleeder screw removed. Replacing the master cylinder cap won't help since it has to be vented enough to allow for a compensation of air pressure on top of the brake fluid reservoir. Automotive hydraulic brake and clutch systems should be flushed periodically to eliminate water and dust that gets pulled in.

Q. Can you provide me with information on the requirement of the price sticker on new cars. Specifically, is it a federal or state law that it must be displayed and posted on all new vehicles until they are sold by a dealer? I know that this is not a repair problem but with your vast knowledge of the auto industry, I thought that you could provide me with an answer or direct me to who to write to or call. Another question is whether or not a vehicle can have an anti-skid brake system added to it? If so, what would be the cost? N.S. Virginia Beach, VA

A. This column is designed to try to answer any auto-related question and not just those that cover fix-it problems. According to the dealers and manufacturers I've contacted, a Monroney (or Manufacturer's Suggested Retail Price - MSRP) sticker is required by federal law to be in the window of cars sold as new in this country. Included on it is all the pertinent information regarding the standard and factory-installed equipment included on that particular car or light truck as well as its VIN (Vehicle Identification Number). The sticker is supposed to be removed only when the vehicle goes to a retail customer and then given to the buyer. All the dealer shops I've contacted have stated that installing ABS after a car was sold would be cost-prohibitive. They also questioned whether a factory would warrant the car if the job was done although one (Ford) said it would be OK. Better contact the National Highway Traffic Safety Administration (NHTSA) office near you.

Q. Our son wants to become an auto mechanic and has gone through an auto program at his high school. He wants to go on to further train and had been interviewed by several advanced training private schools, most of them in the south west. It there a need for more young mechanic now that cars a computerized? Do these schools have a good record? P.H. Seattle, WA

A. I've never come across a computer that could replace a head gasket or a clutch so human technicians are still necessary. The schools are well thought of and as an example, BMW just went into a joint venture with one to provide six months of advanced training for top students.