Polaris Trail Blazer, Service Manual

Page: 162 / 665

Total from Step 1, 2, and 3.
(or from Step 1 only if PTO
bearings were installed).
(A)
Step 5 Result
(B)
Step 6 Result
(C)
Line B + Line C =
(D)
Line D -- Line A = End Play
Subtract Target End Play
-- .012
″
(.3mm)
Shim Thickness Required =
3.17 Polaris Sales Inc.
4/99
ENGINE
EC25PF/EC28PF Engines
Assembly, Cont.
3. Measure total width of main bearings with
bearings. Add the thickness of the spacer
between the bearings on EC28 engines. Record
total measurement.
4. Add all recorded measurements from Steps 1, 2,
and 3 and record the total on line A below. If PTO
bearings were assembled on crankshaft, record
the measurement from Step 1.
5. Measure PTO crankcase half as shown to
determine depth of case. Place a piece of flat
stock on the case mating surface and measure
from this surface to the bearing seating surface.
Subtract thickness of flat stock and record the
measurement on line B below.
6. Measure magneto side case half using the same
procedure. Record measurement on line C below.
(Remember to subtract thickness of flat stock.)
7. Add the readings from steps 5 and 6 and record on
line D. Subtract line A from line D. The result is the
amount of crankshaft end play.
8. If adjustment is required, determine the amount of
spacers needed to achieve proper end play.
Install spacers on crankshaft followed by PTO
bearings.
Correct crankshaft end play is .008
″
- .016
″
(.2 - .4 mm). End play is adjusted by adding or subtracting spacer
washers from between the inner PTO end bearing and the crank wheel. Two different thickness spacers are avail-
able for EC 25 and EC28 engines:
For EC25PF - PN 3083629 - .008
″
(.2 mm); and PN 3083630 - .004
″
(.1 mm).
For EC28PF and EC38PL - PN 3084778 - .008
″
(.2 mm); and PN 3084779 - .012
″
(.3 mm).
Measure total width
Spacer used on
EC28 engine only
Step 5
Step 6