MAINTENANCE TIP
The signs of negligent maintenance first show up in the cylinders and
pistons. It’s common to see wear on cylinder walls caused by dry cold starts.
This leads to compression loss and, ultimately, diminished power. The
primary cause of this wear is viscosity breakdown of the oil. Heat, friction,
and chemical contamination cause the engine’s oil to lose viscosity (ability to
flow and lubricate). Regular oil changes can avoid this problem.Connecting Rods
As stated earlier, the spinning of the crankshaft causes the pistons to travel up
and down in their respective cylinders. One might wonder how the circular
motion of the crankshaft can produce an up-and-down linear motion of a piston.
The answer lies in the design of the mechanical linkage of the connecting rods
that connect the pistons to the crank. The connecting rod connects to the
crankshaft journal through the use of a bearing cap. The bearing cap is a separate
piece that is bolted to the rod. If you were to remove it, you would see a bearing
installed in the rod. This design allows the rod to ride up and down as the crank
spins on a smooth lubricated surface.