The flywheel housing is located on the block by two ring dowels from the factory. If a flywheel housing is removed, it can be reinstalled with the ring dowels in place, but alignment must be checked with the following alignment procedure.
If the alignment does not meet specification, the ring dowels must be removed and the housing must be realigned without the ring dowels.
The flywheel housing bore and surface must be in alignment with the crankshaft to prevent possible damage to the engine, the clutch, or the transmission.
Attach a dial indicator to the crankshaft. Use mounting tool Part Number ST-1325 and indicator Part Number 3376050.
The dial indicator can be mounted by any method that holds the extension bar of the indicator rigid so it does not sag. If the bar sags or the indicator slips, the readings obtained will be inaccurate.
Position the indicator in the 6:00 o’clock position and the gauge at zero.
Slowly rotate the crankshaft. Record the readings obtained at the 9:00 o’clock, 12:00 o’clock, and 3:00 o’clock positions as (a), (b), and (c) in the concentricity work sheet. Recheck zero at the 6:00 o’clock position.
The values for (a), (b), and (c) can be positive or negative. Refer to the accompanying figure to determine the correct sign when recording these values.
Do not force the crankshaft beyond the point where the bearing clearance has been removed. Do not pry against the flywheel housing. These actions can cause false bearing clearance reading.
Rotate the crankshaft until the dial indicator is at the 12-o’clock position and zero the gauge.
Use a pry bar to raise the rear of the crankshaft to its upper limit. Record the value as (d) in the concentricity work sheet. This is the vertical bearing clearance adjustment and will always be positive.
Mark the total horizontal value on the horizontal side of the chart and the total vertical on the vertical side of the chart.
Use a straightedge to find the intersection point of the total horizontal and total vertical values. The intersection point must fall within the shaded area for the flywheel housing concentricity to be within specification.
Using the total horizontal and total vertical values from the previous example, the intersection point falls within the shaded area. Therefore, the flywheel housing concentricity is within specification.
Use the accompanying chart for SAE 1, 2, and 3 flywheel housings.
If the intersection point falls outside the shaded area, the ring dowels must be removed and the housing repositioned.
The ring dowels are not required to maintain concentricity of the housing; the clamping force of the capscrews holds the housing in place.
After the ring dowels are discarded, install the flywheel housing on the engine.
To position the housing, tighten the capscrews enough to hold the flywheel housing in place, but loose enough to enable small movement when struck lightly with a mallet.
Recheck the concentricity. When concentricity is within specification, tighten the capscrews to the specified value.
The dial indicator tip must not enter the capscrew holes, or the gauge will be damaged.
Install a dial indicator as illustrated.
The extension bar for the indicator must be rigid for an accurate reading. It must not sag. Position the indicator at the 12:00 o’clock position. Adjust the dial until the needle points to zero.
Continue to rotate the crankshaft until the indicator is at the 12:00 o’clock position. Check the indicator to make sure that the needle points to zero. If it does not, the readings will be incorrect.
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