In case flywheel has been removed, then the required apparatus to replace it is likely to be present. Having done a complete overhaul of the entire engine, it is recommended to check the crankshaft endfloat, which is defined as the distance between the inner side of the flywheel boss and the rear main bearing shell flange. The gap is minimized by shims which are required to be installed before the oil seal and it is difficult to push them in after the oil seal, but it is difficult to remove the shims after fitting without breaking them. In case the main bearing shell is renewed, the original shims would probably be the correct ones because wear on bearing shell flange is present. The amount of shims required to produce the necessary total thickness is always three (6 sizes are available 0.24 mm, 0.30 mm, 0.32 mm, 0.34 mm, 0.36 mm, 0.38 mm), and the thickness of the third shim is determined. The four dowel pegs are to be installed in the crankshaft flange with a proper fitting in the flange and the flywheel since any loose fitting may cause the flywheel to be loose despite the nut being tight. The fine O ring seal in the flywheel flange recess would need to be replaced before the flywheel is installed. It is essential to hold the flywheel firmly in place and be kept square but ensure that it is placed above the dowel pegs, in case of difficulty in positioning, a scrap of wood can hold the flywheel in position. When it is found positive, the center bolt and washer must be replaced and tightened finger-tight then it must be tightened carefully to pull in the flywheel, but not too tight lest the dowel always pierce the holes and damage the dowel pegs. To ensure proper crankshaft endfloat measuring with dial gauge micrometer by placing the flywheel face against the center bolt, the center bolt should be tightened at least 75 ft lbs and move the crankshaft back and forth to gauge the float. Calculations of the thickness of the third shim is that which is given by the measured float, less 0.10 mm and any three shim may be used as long as the total thickness is the same as that of the two in place and the calculated third shim. Once the right shims have been picked, the flywheel must be taken out, the shims placed and the oil seal attached and then the flywheel replaced in the same fashion. It takes a tightening of 253 ft lbs (35 mkg) to tighten the center bolt and the flywheel can be attached in the same fashion as it was removed i.e. by a flat bar or angle to hold the flywheel pin while tightening the nut. The correct torque is essential to avoid vibrating flywheel to loose and too much torque may lead to undesirable stresses. Also, the flywheel bolt has an inbuilt roller bearing that is used to support the transmission input shaft, which ought to be in excellent condition and ought not to be over-greased.