Owner's manual

5. This pump is required to pull usually cold oil through two 7/8" I.D. lines as opposed to a
stock system's 1/2" I.D. passageway, so it may react a little slower. Because it has a tougher
job, any gear scoring due to foreign debris will start to inhibit the pumps priming ability.
The oil filter will catch this debris but only after going through the gears! Replacement gear
sets for this pump are Milodon part #21817. Pump O-ring and gasket rebuild kit is Milodon
part #21590. Externally adjustable pressure regulator is Milodon part #21550. NOTE:
21815 does NOT use the stock Chrys o-ring around the gear.
6. The depth of the gear set in the pump housing is very important in the pump's ability to
prime. This pump has been factory measured to be between .0015" and .004", any less will
score the cover, any more will result in poor priming. If you replace the gears this will need
to be checked at that time.
Pump Shaft - Length of distributor drive shaft should always be checked to be sure that shaft
is not bottoming out in gear causing this gear to dig into and ruin the pump cover. A
minimum of .060" shaft end clearance is required. Shaft should be shortened if necessary.
The Milodon #21513 and #21523 pump shafts are required by the 21815 pump equipped
engines. When a steel bodied high volume pump is used, the 21505 and 21525 pump shaft
and gears are required. When a steel bodied high volume pump is used with a dual line
spacer the long length pump shaft #21500 and 21520 are required.
Pickup Assembly – The pickup whether swivel or static will attach the fittings in the same
way. The fitting is a “bulkhead” style that has a groove cut into the long thread section that
the O-ring will sit in. Use a little oil on the fitting threads so avoid galling. With the jam nut
and the washer threaded onto the fitting, slide the fitting through the holes in the pan. The O-
ring will then be installed on the fitting inside the oil pan. Align the O-ring on the unthreaded
groove. Use the jam nut to adjust the fitting position in or out to correctly align the O-ring in
its groove. Slide the pickup up to the fitting and screw the fitting into the pickup. The final
tightening will be by the jam nut once the desired fitting angle has been determined.
When using the swivel pickup, make sure that throughout the pickup’s sweep forward and
rearward is kept at an even ¼” to 3/8” all the way through. That is not ½ at one end and 1/8”
at the other.
1/2014