Ford's 289 small-block engine uses a very simple design, but mistakes in the building process can still be made. Perhaps the most common mistakes when rebuilding a 289 include failing to ensure that the timing gears are aligned properly, and installing the pistons and connecting rods backwards. Finally, the importance of properly lubricating the new components with engine lube cannot be overemphasized.
The 289 uses two timing gears and a timing chain to ensure that the valves within the cylinder heads and the spark plugs are properly timed. If those gears are not installed correctly, the engine will not start and, in extreme cases, the engine will immediately bend the valves and maybe damage the pistons. The larger gear attaches to the front of the camshaft, while the smaller gear attaches to the front of the crankshaft. A notch is located within the inner circumference of the crankshaft gear, through which a metal key on the tip of the crankshaft slides through to ensure that the gear is fitted properly. On the face of the camshaft gear is a small, circular indentation, which serves as an alignment point. To ensure that the gears are properly installed, the metal key at the tip of the crankshaft gear must be directly bellow the indentation stamped into the camshaft gear. An imaginary line should cross both points.
Upon first glance, there does not appear to be any difference between the sides of the 289's pistons or connecting rods. Upon closer inspection, you'll notice a small notch on one side of the top of each piston. That notch must face toward the front of the engine to ensure that the piston is installed properly. The connecting rods are similarly marked, but with a number rather than a notch on one side of the base of each connecting rod. One number is stamped into the connecting rod itself, while the second number is stamped into the connecting rod's cap. Both numbers are identical, and must face the same way when installed.
The most critical time of any engine overhaul is the period when the engine is first started. Because most, if not all, of the components within the engine are new, the components are particularly susceptible to wear if not properly lubricated. For that reason, it is important to lubricate the critical moving part within the engine with assembly lube, particularly the camshaft, crankshaft and connecting rod bearings. Assembly lube, as opposed to engine oil, is specifically designed to lubricate those components when the engine is first started, and should be liberally applied.
