The push for fuel economy has two benefits: using less gas, and fewer emissions. Boulder cars and trucks run cleaner than ever. Boulder people may not realize that the first federally mandated pollution control device came out almost fifty years ago.
Boulder folks that were around in the early 60’s may remember that the PCV valve came out on 1964 model cars. PCV stand for Positive Crankcase Ventilation. 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 fuel is burned in the family car 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 environment in Boulder.
Enter the PCV valve. It’s a small, one-way valve that lets out the gases from the crankcase, and routes them back into the air intake system where can be re-burned in the engine. Fresh air comes into the crankcase through a breather tube. This makes for good circulation in the crankcase. And that gets the bad air out. As you can imagine, the valve gets gummed up over time.
Boulder drivers that skip oil changes now and then will notice that the PCV valve gets gummed up even faster. If the PCV valve is sticking in your family car, the gases won’t circulate as well, leading to increased pressure in the crankcase. That, in turn, can lead to oil leaks. Fortunately, the PCV valve is very inexpensive to replace at John’s Auto Care. Some can even be checked for function by your cheerful service technician.
Manufacturer’s usually recommend they be changed somewhere between twenty and fifty thousand miles. Unfortunately, PCV valve replacement is left out of some family car owner’s manuals, but at John’s Auto Care, we will make sure your PVC is replaced if needed.
All of us Boulder car owners can do our part for the environment. Watch that lead foot, stay on top of our automotive maintenance and don’t forget to replace our PCV valve.