(1) Apply a rubber base sealant as required to avoid leakage between endplates and blower housing.
Be sure no sealant protrudes into blower housing. Also, sealant must not prevent endplates from
laying against the housing.
(2) Install blower front endplate, making sure mark TOP on outer ribbed side is at top of blower housing.
(a) Check dowel pins. Dowel pins must project .380 inch from flat inner face, and .270 inch from outer
face of front endplate to assure proper alignment of endplate to housing and cover to endplate.
(b) Place blower housing on a bench with top of housing up, and front end of housing facing outside of
(c) Position endplate in front of blower housing with flat finished face of endplate facing housing and
end marked TOP facing flanged side of housing. Then, start dowel pins straight into dowel pin holes in housing. Push or
tap endplate against housing.
(d) Insert two fillister head screws through endplate and thread them into housing. Tighten screws to 5-
10 Ib-ft torque. Do not use lock washers on these screws.
(3) Assemble blower rotors in blower housing and front endplate as follows:
Rotors must be assembled in blower housing with omitted serrations in rotor shafts aligned.
(a) Place an oilseal pilot on short (non-splined) end of each rotor shaft. Then, place rotors in mesh
with omitted serrations in shafts in alignment as shown in Figure 6-8.
(b) Insert blower rotors with oilseal pilots straight into blower housing with right-hand helix rotor at top,
flange side of housing. Then, push rotor shafts and oilseal pilots on through oilseal in front endplate as shown in Figure
(c) Remove oilseal pilots from rotor shafts.
(4) Attach blower rear endplate to blower housing as follows:
(a) Reverse blower housing on bench (rear end of housing facing outside of bench).
(b) Place an oilseal pilot on serrated end of each rotor shaft.