Auto Service World
Feature   March 1, 2008   by Nestor Gula

Spring is not only a change in season, but a time to spring into action

Winter months can be tough on a car's engine. The change in season offers an opportunity to sell some maintenance work to customers.

There is no doubt that cars are built much better these days. There really is no comparing a modern car to one built twenty years ago. The new breed of cars are much more reliable, much more efficient and the quality of materials is better, and the electric and engine systems work exceedingly well.

If fact, they work so well that few people are coming in for a regular service check in some cases. But vehicle owners really need to be dissuaded from thinking that today’s cars can forgo the regular maintenance schedules of their parent’s vehicles.

Even long-lasting filters have to be maintained

Take for example, the oil filer. A growing number of new vehicles are coming equipped with longer-lasting oil filters and manufactures tures of engine oils are developing oils that can go longer between changes. Only there is still a lot of controversy amongst independents in Canada as to what exactly should the change intervals on these extended drain oils and filters be. In fact, it even sparked a rather lively e-mail exchange amongst some of SSGM’s most dedicated readers. For example, one shop asked that if new synthetic oils are made to last longer than ever before, sometime even longer than the recommended change interval of the oil filter, at what point should the shop schedule an oil and filter change for a customer? Should one follow the change interval of the oil or the filter? And what is one to do with some filters that are said to last the lifetime of the vehicle? A shop in Red Deer, Alberta responded by saying it follows a rule that its shop’s service writers and technicians recommend that any type of oil, even one of the new synthetic ones that come with an extended drain interval, not be used past 10,000 km. It is still best that all oil filters and oil be replaced every 5,000 km, was this shop’s rule. The reason is simple, while a customer may be using synthetic oil that is rated to last longer, that oil still get dirty and gets dirty just as quickly as any conventional oil. Another shop said that oils and filters really should be replaced on any vehicle every four months or 7,000 km. So amongst shops, the rule seems to be not to let customer get lulled into a sense of false safety by thinking that long drain intervals on new motor oils or the filters means they can ignore regular maintenance intervals.

The same goes for the air filter. Today’s air filter technology has changed tremendously from the time of the lowly paper-based air filter. While paper is still used in many low-end, inexpensive air filters, today’s filter manufacturers have designed filters that use highly complex cotton and synthetic media that can trap many smaller air-borne particles. And a new breed of air filter is designed to use a complex blend of fibers and specially-formulated oils to capture particles. While many of these new filter designs are made to last much longer than traditional paper-based filters, they still need to be inspected regularly and changed. Air filters that use an oil resin to help in the filtration of particles also must be cleaned regularly and the oil replaced in the filter media. Internal cabin air filter also need to be regularly checked and replaced. If there is a drawback with cabin air filters, is that sometimes they are very difficult to access, causing much cursing of car designers by technicians who struggle to reach them.

O2 sensors, wire sets need care and attention

One the most critical components in today’s automobiles are the oxygen sensors. A faulty or slowly deteriorating sensor will affect a car’s drivability and may, if the sensor is left unchecked and uncorrected, cause a car to fail its regular emissions test.

Jamie Salinas, product manager with at Robert Bosch in Mississauga, Ont. notes all car manuals explicitly say that periodically a technician should change the oxygen sensors for the smooth running of the vehicle.

“Simply, these sensors control the emissions of your car and they make the car run more efficiently,” he continued. He added that changing the sensors will contribute to a better fuel efficiency of the vehicle and make it less polluting.

Most sensors fail because of age, becoming clogged with engine soot and other contaminants. They can also be damaged by poisoning from sulfur in the fuel, antifreeze leaks that get to the sensors, as well the exhaust becoming fouled with lead, silicone from damaged gaskets or oil ash.

Salinas warns sensors should be replaced strictly following the OEM guidelines and specifications.

Twenty years ago, an auto tune up would consist of replacing the cap and rotor, the sparkplug wires and the sparkplugs themselves. “There used to be a traditional of changing the cap and rotor and wires and plugs yearly,” said Stan Viezner Jr., president of Prenco Progress and Engineering Ltd. in Toronto. The company makes wire sets for engines as well as brake cables and many underhood and chassis components. “That was driving the entire replacement need. Now you have plugs, platinum plugs, which are good for 100,000 kilometers.” According to Viezner, the long intervals between service calls lead people to neglect certain components of their engine.

“You have to replace the ignition wires on a regular basis,” he said. “The problem is that the wires themselves are exposed to very high heat. The heat actually ages the wire very quickly. The high heat in engine compartment plus the high current going through the wires takes its toll. The insulation quality breaks down. Although the insulating materials are extremely good there is an effect, especially when combined with humidity and the constant fluctuation in temperature.”

According to Viezner, the seals around the plugs are important and will be the first place the degradation takes place. The more humid an environment the greater and more detrimental the effect on the lifespan of the wires will be. He added that wires are not replaced frequently enough, as well.

“The wires should be changed on an annual basis,” he said. “Most people would replace them every couple of years or every three years, when changing their sparkplugs. That drives the replacement schedule for the wires themselves. If you change the plugs and wires you will be surprised how different and better, your performance and fuel economy will be.”

Belts and hoses are tough, but will fail when neglected

Viezner says that the timing belts take a great deal more abuse now than they did years ago. They run the air conditioning system, the alternator, water pump power steering pump and more. These should be inspected at every service call and replaced when needed. Something to keep in mind is to regularly inspect the teeth or cogs to make sure they have not worn.

While checking the belt it is wise to inspect the belt tensioner. These simple devices are known to fail on occasion and will disable the vehicle when not working properly. Technicians should look for any back and forth movement (oscillation) of tensioner arm with the engine running. If large or continuous swings occur, it is recommended that the tensioner be replaced. With engine running, check the belt tracking — the belt should track in one area of pulley, not over edges or wander from side to side. Also listen for squeaks/squeals when the engine is running. With the engine off, check for play (looseness) and smoothness in the tensioner pulley or arm. Also, with the belt removed manually rotate the pulley and listen for squeaks or grinding. Replace tensioner is recommended if any roughness or rust is found.

Hoses are another item that requires regular inspection. Randy Chupka, Marketing Manager, Automotive Replacement Markets at Gates Canada Inc, said, “An overheated engine due to cooling system failure is one of the most common causes of roadside breakdowns. When coolant is lost, or when a part malfunctions within the cooling system, the engine is certain to get too hot. Overheatin
g results in accelerated wear from within the hose and early hose failure. They may develop micro-cracks within the hose tube that allow the coolant to attack the hose reinforcement. In time, the reinforcement will weaken.”

Combined with high under-the-hood heat and constant flexing, “the hose could rupture or leak under normal pressure before it has reached its expected service life,” added Chupka. “To avoid this failure mode, Gates suggests a safe service life of four years for all coolant-carrying hoses, especially the upper radiator and bypass hoses. After four years, the incidence of hose failure increases sharply.”

To inspect the hoses, make sure the engine is turned off and cool. Squeeze the hose two to four inches from the connector (ends) where the breakdown first occurs. “You can often feel gaps or channels,” said Chupka. “The middle of the hose may feel solid while the end feels mushy. If the ends feel soft, change the hose immediately to avoid a potential future breakdown.”

Hoses that are not involved in fuel-or oil-related work can be damaged if they come in contact with fuel and oil. Oil will cause the rubber of hoses to swell and some water pump lubricants have certain additives that can cause damage to the inside of a hose. One problem that has shown up in some cases is elect rochemi c a l degradation (ECD), which can cause a sudden failure of radiator, heater or thermostat bypass hoses.

ECD is caused because the hose, the liquid coolant in the hose (ethylene glycol antifreeze and water) and the engine and radiator fittings form a galvanic cell. The chemical reaction of this combination causes microcracks i n

the hose which allows coolant to attack the hose reinforcement. Because the hose is subjected to high heat and flexing during normal operation, that hose can develop a pinhole leak or even rupture under normal pressure. If a technician suspects that such a problem is happening to a customer’s car, the solution is to replace the hose with one that is electrochemically resistant.


Gates Canada Inc. Prenco Progress and Engineering Ltd.

Robert Bosch

Print this page


Have your say:

Your email address will not be published. Required fields are marked *