I had a great time renewing acquaintances at the NAFA conference in Chicago. I also came away with some interesting observations.

Fleet operators are pretty unhappy with the positive crankcase ventilation systems now in use. Much of the unhappiness stems from misunderstanding and lack of information. The PCV valve must be maintained to avoid engine damage. Failure to maintain the PCV system can lead to crankcase sludging, bearing failure, carburetion troubles and early engine failure. The heart of the typical PCV system is a valve with only two moving parts-a finely calibrated spring and a plunger. The valve is also the reason that proper maintenance is needed to prevent engine damage. Flowing past the valve are water vapor, acids, products of combustion, unburned fuel and in some cases even a minute amount of oil. The materials tend to deposit in the valve, making it necessary to clean the valve to maintain the proper flow through the system. If service is completely neglected, the valve can become clogged and the corrosive gases will remain in the crankcase to dilute oil and produce sludge.

Actually, the service problem on PCV systems is no more severe than with many other routine maintenance items. Oil and oil filter changes, for example, are accepted by fleet operators without question. The problem with positive crankcase ventilation is that it is not generally known or understood by many maintenance men.

Many fleet administrators said they prefer their vehicles without PCV systems. I feel that this is negative thinking. The PCV system is a positive step in the fight against air pollution. If maintained properly, it will do its job and not create any service problems. The important thing is to make certain that the valve is checked every 5,000 miles to make certain it is functioning properly. Faulty valves should be replaced.

Auto engineers admit that the present crankcase ventilation system is not perfect. Ideally, the perfect system would be one that requires no servicing. I am sure that the auto companies are aware of the problem and are working on a solution. However, according to Detroit observers, there is no easy solution in sight. Fleet operators will have to put up with the present PCV systems-and service them.

In addition to aiding in controlling air pollution, auto engineers credit the PCV system with three other benefits:

Somewhat better fuel economy. The improved economy is the result of unburned gas in the blowby, which normally would be vented to the atmosphere, being returned to the engine.

Cleaner oil which makes possible a host of other advantages that add up to greater engine and oil durability.
Less oil dripping under the car as the result of the elimination of the road draft tube.

Does your car manual call for the use of premium gasoline? If it does, you still might be able to use a less expensive grade of gas. A Ford Motor Co. engineer told the NAFA conference that he drives a Lincoln Continental and does not use premium gasoline but rather a blended gas. He considers the savings the substantial and claims that he gets the same performance as if premium gasoline were used. It is easy to check if you can get by without using premium gasoline. Fill up the tank with the blend and if no ping develops, you're in business.

Gasoline costs represent about one-third of the total cost of operating business. Gasoline costs represent about one-third of the total cost of operating a car. If costs could be cut just 1/10th per mile, it would result in a savings of $4,000 for a 150 car fleet. AUTOMOTIVE FLEET's editorial board currently is developing an article on gasoline costs. It is scheduled for publication in July.

Had an interesting inquiry from a reader who wants to know if there are any firms who rent antique, classic or vintage cars. I know of no such firms, but I'm sure that someplace there is an enterprising entrepreneur who is renting old cars.