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Q1) How much end gap is OK for new standard rings in a standard bore on my John Deere B. I have .044. I think that is well within range. Answer = Acceptable ring gap is generally 0.003 - 0.004 inches per inch of bore. So for a four-inch bore, you should expect between 0.012 and 0.016-inches of ring gap. Q2) How much should the connecting rods be torqued? They are the babbited style. Answer = Tighten to 75 ft-lbs, then more as needed in order to insert cotter pin. Q3) What is the torque on the head bolts? Answer = Tighten gradually from center outward to 96 ft-lbs. If you have a really late B (248284-up) with heat-treated studs, you can take them to 104 ft-lbs! Q4) Recommendation on how the ring end gaps should be staggered. Answer from the JD-H Restoration Guide, and should pretty much apply to any two-cylinder tractor = Deere literature for the model �H� does not appear to address this issue. It is not discussed in any of the early IPLs, nor is it mentioned in the SM. Because rings have the capability of rotating during service, some say that gap position is unimportant. However, to minimize cylinder leakage, it is prudent to avoid positioning the gaps in a straight line. Even though compression losses are quite small through a ring gap, such losses do occur. If the gaps are staggered, such blow-by is diminished because of the labyrinth seal effect created by the maze-like path that gases must travel to escape through ring end gaps. Authoritative references, such as piston ring manufacturers, state that staggered rings minimize the possibility of cylinder scuffing when an engine is started for the first time. Automotive service manuals almost always mandate staggered ring gaps, and many manuals even show illustrations that dictate the specified location of each ring gap. Q5) What should be the clearance on the rod bearings? Answer = Operating clearance for your rod bearings should be from 0.002 - 0.004 inches.
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