Crank Preparing

CRANK PREPARING

Advantages of crankshaft "wedging" for 'A' & 'B' series engines:

Removing metal from the crank pin sides of the crank has the effect of increasing the counter balance mass on the opposite side, of which there is too little.

Insufficient counter balance weight is what causes a lot of main bearing wear.  This is most pronounced on one side of the crank journal, and tends to show more on three main bearing engines, and in particular 1300 transverse.

Inline 1275s suffer from the same problem, but not so noticeably as the crank is normally harder (tuftrided EN16T from the factory).

Another of the high points of this "wedging" operation is that it removes the square edged, stress raiser notches that the factory machine in during initial machining setup, many crankshaft cracks start from those points.

The fact that the crank is lighter, and more importantly, has reduced inertia is another point in favor of this operation.

At the present time, cost and order number:
Z005 $205.00 for wedging 'A' or 'B' series crank.

Heat treating of this spec. of crank is highly recommended, cost and order number:
Z014 $130.00 (Includes straighten/polish).

Metal is being removed from these points.

Mini crank set up for machining to increase 'effective' counter balance.

1275 crank: wedged, plasma nitrided, ground/polished, prepared oil ways and balanced.  (ground to either 0.010 or 0.020" U/S)

Metered oil hole on MGA crank. The brass plugs have been pulled, and these special screw in ones installed.