Thom's Four Wheel Drive

Today we want to talk to CHICAGO drivers about timing belts. They're something that many drivers don't know much about and yet your vehicle won't run if it's broken – and it could cause many thousands of dollars damage if it does break. A broken timing belt is usually a tale of woe. Even though timing belt replacement is scheduled in the owner's manual, it's not the kind of thing that most CHICAGO area auto owners remember because it's not well understood.Let's review what a timing belt does. As most know, the engine's power is generated in the cylinders. A piston rides up and down in the cylinder. During the first down stroke, an intake valve at the top of the cylinder opens and air and fuel is drawn into the cylinder. Then the piston returns to the top, compressing the fuel and air mix. At the top, the spark plug fires, igniting the fuel, pushing the piston down in the power stroke. As the piston once again returns up in the final stroke of the cycle, an exhaust valve opens at ... read more

Don't you hate it when you hear that squeal from under the hood when you're zipping down a busy CHICAGO road? It usually means there is a problem with the serpentine belt. The serpentine belt powers a lot of engine accessories. It runs the alternator - which charges the battery; the water pump - which cools the engine; the air conditioning and the power steering pump. All are pretty important parts. It is called a serpentine belt because it snakes around a bunch of engine components. Serpentine belts are amazingly tough. They can last for years and go long distances. Like all moving parts, however, they eventually wear out. If your belt breaks while you are driving around CHICAGO, everything will come to a halt within minutes. You need to stop the vehicle immediately or it will overheat, potentially causing engine damage. You can be sure that it won't happen at a convenient time or place. (As if there was a convenient time or place!) You might even need to get your veh ... read more

The crankcase is the lower part of the engine where the crankshaft is housed and where the engine oil lives. The crankshaft is connected to the pistons that power the engine. When you are diving around CHICAGO, fuel is burned in your vehicle engine, it pushes the pistons down and the crankshaft rotates and sends power to the transmission. Some of the explosive gases from combustion squeeze past the pistons and down into the crankcase.Now this gas is about 70% unburned fuel. If it were allowed to remain in the crankcase, it would contaminate the oil and quickly turn it to sludge. Sludge is like Vaseline and clogs passages in the engine, leading to damage. Also, the pressure build up would blow out seals and gaskets. So in the old days, there was just a hose that vented the crankcase out into the air. Obviously, not good for our air quality in CHICAGO, Illinois.Enter the PCV valve. It's a small, one-way valve that lets out the gases from the crankcase and routes them back into ... read more

Today, we are talking about your PCV valve. Unburnt fuel is forced into the crankcase as your engine runs.  The PCV (positive crankcase ventilation) valve vents this unburnt fuel and oil vapors from the crankcase and sends it back into the air intake system to be burned in the engine.  A clogged PCV will not allow these vapors to escape. This can dilute and contaminate the oil, leading to damaging engine oil sludge. It can also cause vehicle engine corrosion, something we see occasionally at Thom's Four Wheel Drive. At high speeds on Illinois freeways, the pressure can build up to the point that gaskets and seals start to leak. Back in the old days, vehicles were simply installed with a hose that vented these gases out into the atmosphere. But starting in the 1964 model year, environmental protection laws required that these gases be recycled back into the air intake system to be mixed with fuel and burned in the vehicle's engine.This is much better for ... read more