Leak Could Lead to a Wave of Ills
Question: Is an oil leak a major problem?
Answer: It depends on the type of leak. They can be a minor nuisance or a major catastrophe.
Without plentiful and clean oil, a car’s mechanical systems can sustain massive damage. But oil is also relatively cheap and in many cases it makes perfect economic sense to just keep replenishing oil that is lost through various seals and gaskets rather than fixing the problem causing the leak.
Cars have oil in a lot of places: the engine, transmission, power steering pump and brake system, among others. Most cars leak somewhere as they get old.
Engines can lose oil as a result of it burning up or leaking through seals and gaskets. When an engine burns oil, it means the valve seals are failing or that piston rings are worn out or plugged. Unless the engine is disgorging massive amounts of oil, it is usually cheaper to replace the lost oil than fix the cause of the burning.
But one problem with ignoring oil burning is that it will eventually poison and then plug up the catalytic converter, said Norm Hudecki, director of technical services for Valvoline oils.
A plugged up catalytic converter, a device that purifies contaminants in the engine exhaust before passing it to the muffler, will cause back pressure in the exhaust system. As back pressure rises, the engine will lose power.
The good news is that since 1995, converters are warranted for 100,000 miles. In pre-1995 models, converters are warranted for 50,000 miles.
Oil leaks through seals and gaskets are another issue. Often they result from an owner not frequently changing oil when the car was new. Sludge deposits harden and damage gaskets and seals.
Sometimes, using a heavier weight oil can slow the rate of leakage. In warm Southern California, you can reasonably go up to a straight 50 weight oil to help control leaks, Hudecki said.
In some cases, a leak out of a seal or a gasket indicates major mechanical trouble. For example, a leak from a crankshaft seal indicates the engine’s main bearings are shot. The same is also true of transmission and steering pump leaks. In brake systems, any hydraulic leak is a major safety issue and should be repaired immediately.
* Vartabedian cannot answer mail personally but will attempt to respond in this column to automotive questions of general interest. Do not telephone. Write to Your Wheels, 1875 I St. N.W. #1100, Washington, DC 20006.
