MSD 84697 Chevy V8 Crank Trigger Distributor Installation User Manual
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INSTALLATION INSTRUCTIONS
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Figure 3 Checking Oil Pump Shaft to the Distributor Shaft Overlay.
PREPARING THE DISTRIBUTOR
O-RING SEALS
The MSD Billet Distributor features two O-ring
grooves in the bottom lands of the housing to
seal the oil gallery. These O-rings should only
be installed if the block has been modified as
shown in Figure 2.
ADJUSTABLE SLIP COLLAR
The MSD PN 8558, Distributor features an adjustable slip collar. This collar provides an adjustment
to accomodate variations in block height, modified intakes or heads. It is recommended to check the
slip collar setting before installation. MSD offers a special tool, the 3-In-1 Distributor Set Up Tool, PN
8599, to make these adjustments accurately. If the tool is not available, follow this procedure.
1. Loosen the slip collar and insert the distributor into the engine until it bottoms out against the oil
pump drive.
2. After it bottoms out, raise the distributor 0.010" - 0.030" then slide the slip collar down into the
position and tighten it.
CHECKING THE OIL PUMP TO DISTRIBUTOR SHAFT OVERLAP
The proper overlap between the distributor shaft and the oil pump shaft is very important. The tongue
of the distributor shaft should fit into the groove of the oil pump shaft by at least 1/4". To check this:
1. Measure the distance between the base of the slip collar to the tip of the distributor shaft (Figure 3).
2. Using a straight edge, measure the distance from the intake manifold distributor flange to the top
of the oil pump intermediate shaft (Figure 3).
3. Take the two measurements and subtract
them. The difference is the overlap. If
there is not enough clearance or too much
clearance, a different oil pump shaft is
required.
CHECKING GEAR MESH
It is recommended to check for proper gear
mesh between the cam gear and distributor
gear. To do this, coat the distributor gear
with moly grease and install the distributor.
Next, crank the engine over several times.
Before pulling the distributor out, make sure
the rotor is in the position that lines up with
the original removal mark. Then pull the
distributor out and inspect the gear pattern
shown on the grease. The proper mesh will
leave an even pattern in the middle of the
gear. Adjust the slip collar to obtain the correct mesh.
Figure 2 Modified Block to Accept the O-Ring Seals.