Re: Question for Tom Endy-Differential Pre-Load Tool
Homemade Schedule 40 PVC Model A Ford Differential Preload Adjusting Tool To fit Over Spider Gear Tri-Axle:
1. Material Items; (under $10.00 without PVC Glue):
A. 3" Schedule 40 PVC MIPT Clean Out Plug, Model #C4818HD3 =
$2.30. (Refer to modifications below in Paragraph 2).
B. 1/8" thick x 1-15/16" wide x 3/4" deep, (top to bottom), aluminum flat
bar to fit diagonally in the square opening of above Item A after
clean out plug modifications specified in Paragraph 2. below.
C. 3/4" Schedule 40 PVC pipe, cut 2' - 6-3/8" long. (Cut pipe from a new
10 ft. long 3/4 in. PVC pipe = $2.87.) On bottom end of PVC pipe, drill
a 1/8" hole through both sides of pipe, 3/4" upwards from lower end of
pipe. With a hacksaw, provide a 1/8" wide x 3/4" long up & down
slot in both bottom sides of PVC pipe, from cut off end of the pipe to
the above 1/8" drilled holes.
D. Provide and glue a 3/4" PVC coupling on the top end of the above
Item C PVC pipe = $00.34.
E. Provide and glue a 3/4" x 1/2" Schedule 40 PVC reducer in top
end of Item the above formerly glued Item D. coupling = $1.11.
F. Provide and glue a 1/2" plug in the top end of the above Item E. PVC
reducer = $00.96.
G. Optional to help maintain 3/4" PVC pipe in a vertical position when
turning: Cut a 3/4" PVC coupling to 7/8" long, burnish inside of
PVC coupling with sandpaper so it slides easily over the above Item C.
3/4" PVC pipe. Position and glue this burnished coupling in place such
that the bottom end of this coupling is 2' - 2-1/2" from the slotted
bottom end of the above Item C. 3/4" PVC pipe.
2. Preparing above Item A Clean Out Plug:
a. With a hacksaw, cut off and remove the top, flat square part of the
above Item A PVC plug thus providing a square thru-hole in said
square part of the PVC plug.
b. With a hacksaw, if required, cut grooves in the inside corners of the
square open hole in the clean out plug for the above Item B. aluminum
plate to fit tightly.
c. Place the 3-1/2" PVC clean out PVC plug on a sheet of paper, and with a fine felt
tipped marker, scribe a circle around the outside threaded circumference of
the PVC clean out plug.
d. Using a grammar school cheap compass with a pencil, locate the
center of the drawn circle to determine the radius of this circle. Next,
place the metal point of the compass on the marked circle's
circumference and scribe (6) consecutive radius marks on the
circumference of the circle. (E.g., the circumference of a circle can be
divided into (6) equal segments using the radius of the circle.)
e. Chose any (3) marks which will fit directly over the (3) axles on a
Model A spider gear Tri-Axle and provide (3) 90 degree vertical marks on the
threaded sides of the PVC plug.
f. Clamp a 2x4 on edge, with one 1-1/2" side flush with the threaded
side of the PVC plug. With a 3/4" spade bit, next drill a hole in the
2x4 and also through the threaded side of the PVC plug, and repeat same
for providing (3) holes. With a round file, custom fit (3) recessed holes to fit snugly
over the (3) axles of the Model A spider gear Tri-Axle.
3. Adjusting Model A Differential Preload:
With Model A axle housing positioned in the vertical position, (per Mr. Tom Endy's instructions), after installing the Model A Tri-Axle, place the modified PVC plug over the Tri-Axle, insert the 3/4" PVC pipe slots over above Item B. flat aluminum bar, place socket wrench socket on above Item F. PVC plug, and turn PVC assembly and Tri-Axle with an inch-pound torque wrench to achieve the desired preload.