7
MISCELLANEOUS COMPONENTS:
Replacement Black Cap: MSD 84313 or Holley 566-105
– Rotor MSD 8467 or Holley 566-106
P/N 8583 Bronze Gear, P/N 85832 Cast Iron Gear, P/N 85833 Replacement Steel Gear
– Ford 302
P/N 8581 Bronze Gear, P/N 85812 Cast Iron Gear, P/N 85813 Replacement Steel Gear
– Ford 351C-460
P/N 8585 Bronze Gear, P/N 85852 Cast Iron Gear, P/N 85834 Replacement Steel Gear
– Ford 351W
P/N 8531 Replacement Cast Melonized Gear, 8472 Oversized Bronze Gear (+0.006)
– Chevy
P/N 8471 Bronze Gear
– (0.500”) ID Chevy
P/N 85631 Bronze Gear
– Pontiac
GEAR INSTALLATION ON FORD DISTRIBUTORS:
It is recommended to send your Ford Distributor to MSD to have a new gear installed. The MSD Tech Department can
be reached at 888-258-3835. The installation process requires a press fit and the need for special tools to achieve
proper installation without damaging the shaft, gear or housing. If returning the distributor to MSD is not an option, a
quality machine shop may also be able to install your new gear.
1.
With the endplay of the distributor shaft removed, measure the distance from the bottom of the gear to the bottom of
the mounting flange (
Figure 14
). It should be within the specifications shown.
2.
Scribe a mark on the shaft at the bottom of the gear. This will aid in the installation position of the new gear.
3.
Remove the original roll pin and remove the press fit gear. Use extreme care not to damage the end of the shaft where
it meshes with the oil pump.
4.
Position the gear so the new roll pin will enter the shaft 90° from the original hole. (Lining up the original hole is
possible, but a new hole will likely be machined.)
5.
Press the new gear into position on the shaft. Measure the distance as shown in (
Figure 14)
before drilling the new
roll pin hole.
6.
Carefully drill a 0.125” hole through the shaft using the gear as a guide.
7.
Install the new 1/8” spiral roll pin.
Figure 14 Gear Installation Specifications
CAUTION: If the gear is installed improperly, severe damage to the
distributor and/or engine block will occur!
