A light lubricant in the class of WD-40 works well on initial installation and does not impede the breaking-in process. Clean the cylinder bores, piston, and rings, and then lightly lubricate when assembling them.
8Sealants and Gaskets Sealing the engine at the oil pan, crankshaft seals, timing cover, intake manifold, headers, and valve covers is a process that deserves attention. Most of these areas that we need to seal are best sealed with quality gaskets of a much better design than those we have seen in the past.
Most of the time, we don't need extra sealant material applied to the gaskets. Again, as with other operations associated with assembling the engine, read the instructions that come with the gaskets to learn how to properly install and use the gasket.
Do not open your gasket kit, if sealed in a vacuum pack, until you are ready to install the gasket. If you open it and it becomes exposed to the air for long periods of time, the gasket will dry out and not perform the way it was intended. Leaks can develop and gaskets can blow out.
Go the extra dollar and buy quality gaskets that are made expressly for racing applications. These units are designed to be used in a racing environment that sees higher temperatures and increased pressures.
If you need to use a sealant material, apply a thin line of material and press the gasket to help spread the sealant. Make sure you do not apply excess sealant that will ooze out from the gasket and become an obstruction to the flow of coolant, oil, or intake gases.
9Proper Distributor Fit A problem that has been seen in the past involves the distributor fit in both the areas of the bottom of the shaft to the bearing installed in the engine as well as the gear fit. We can avoid trouble down the track if we check these fits before we crank the engine.
The supplier to a major distributor once machined the distributor shaft to a smaller dimension than was proper. The shaft literally wobbled around in the larger hole, and failure was just around the corner. Be sure to check the size of the bearing versus the diameter of the distributor shaft.
If the gears don't mesh properly, they will wear very quickly, and the distributor will exhibit erratic characteristics when we are trying to set the engine timing. These gears come in multiple sizes to compensate for slop in the fit between the cam gear and the distributor gear. We can test the fit by rotating the distributor shaft while holding the cam still. There should be very little play in the gears.
10Completing the Assembly The final assembly involves bolting on the water pump, alternator, fan pulley, headers, water connections, and so on. We need to be observant in certain areas to avoid trouble later on.
Closely align all belts that run the alternator, fan/water pump, and oil pump (if it is a dry-sump engine). Any slight misalignment will result in premature wearing of the belts, or worse-a thrown belt. Do not delay fixing a pulley that is not in alignment with the other pulleys.
If you use a high-heat silicone sealant when installing the headers, apply the material to the engine or header flange and then press the header onto the engine. Turn the bolts until the sealant material is flattened, but not too tight, and then allow the sealant to dry. Tighten the header bolts later. If you don't do it this way, the sealant may end up being too thin and you may develop header leaks.
Starting for the first time Most engine mechanics recommend that you always start the engine with the transmission in neutral and with the clutch disengaged. Pushing in the clutch, which pushed the crankshaft forward against the thrust bearing, makes the job harder for the starter and puts unnecessary wear on the crankshaft thrust bearing because the oil has not yet begun flowing to lubricate it. Furthermore, that thrust bearing is not designed for the magnitude of the load a racing clutch can put on it.