(c) Check dowel pins. Dowel pins must project .380 inch from flat inner face, and .270 inch from outer
face of rear endplate to assure proper alignment of endplate to housing and cover to endplate.
(d) Place rear endplate in position in front of oilseal pilots with flat finished face of endplate facing
blower housing and mark TOP on endplate at top flange side of housing.
(e) Place rear endplate over oilseal pilots and start dowel pins straight into dowel pin holes in housing.
Push or tap endplate against housing.
(f) Insert two fillisterhead screws through endplate and thread them into housing. Tighten screws to 5-
10 lb-ft torque. Do not use lockwashers on these screws.
(g) Remove oilseal pilots from rotor shafts.
c. Install blower rotor shaft bearings and gears
(1) With blower housing, rotors, and endplates supported in a vertical position on two wood blocks, install
roller bearings on rotor shafts and in front endplate as follows:
(a) Lubricate one of roller bearings with engine oil. Start bearing, numbered end up, straight on one of
(b) Place installer on top of bearing and tap bearing on shaft and into front endplate.
(c) Install second roller bearing on remaining rotor shaft in same manner.
(d) Place bearing retainers on top of bearings and endplate; then, install retainer bolts and
lockwashers. Tighten bolts to 7-9 Ib-ft torque.
(2) Start end of water pump drive coupling straight into left-hand helix rotor shaft. Then, place a clean shop
towel between blower rotors to prevent them from turning. Install drive coupling retaining bolt and draw coupling and
slinger tight against end of shaft, then tighten bolt to 18 Ib-ft torque.
(3) Affix a new gasket to blower front endplate cover.
(4) Position endplate cover over endplate dowel pins, with large hole in cover toward top of endplate, then
push cover against endplate. Install ten bolts and lockwashers. Tighten bolts to 13-17 Ib-ft torque.
(5) Install ball bearings on rotor shafts and in rear endplate as follows:
(a) Reverse position of blower housing on two wood blocks.
(b) On a blower with ring type oilseals, insert two fillisterhead screws through rear endplate and thread
them into the housing. Tighten screws to 5-10 lb-ft torque. Do not use lockwashers on these screws.
(c) Lubricate one of ball bearings with engine oil. Start bearing numbered end up, straight on one of
(d) Place installer on top of bearing and tap bearing straight on shaft and into rear endplate.
(e) Install second ball bearing on remaining rotor shaft in same manner.