SINGER 251 - Manual (Page 31)

31
THE OIL PUMP
TO REMOVE
1. Loosen the two oil pipe clamping sleeve nuts 52,
Fig. 49.
2. Remove the four screws N2, Fig. 48.
3. Remove the screen frame, screen and oil pump
cover 02, Fig. 48.
4. Remove the locking screw 02, Fig. 49.
5. Remove the impeller P2, by turning it over toward
the RIGHT (clockwise) to loosen it, as instructed
in Fig. 49.
CAUTION:— The impeller P2 is designed to be screwed
to the shaft by means of a LEFT-HAND THREAD and
must be turned over toward the right to be loosened.
Avoid damage to this impeller, as the efficient auto­
matic lubrication of the machine is dependent upon it.
6. Remove the three screws T2.
TO REPLACE
1. Place oil pump body on underside of ma­
chine bed, so that position pins V2, slip into
proper holes in machine casting, as shown above.
2. Replace and securely tighten the three screws T2.
Make certain that machine turns freely as screws
are tightened.
3. Carefully replace impeller P2, turning it over
toward the LEFT to screw it on arm shaft (see
CAUTION at left).
4. Make certain that impeller P2 is not so tight that
it will bind arm shaft. Make certain also that im­
peller clears both top and bottom of interior of
oil pump body, then lock it in position by means
of locking screw Q2.
5. Replace pump cover, screen and frame 02 and
four screws N2, Fig. 48. Securely tighten
screws N2.
7. Carefully pull the oil pump body off the lower
end of the upright arm shaft.
6. Replace two oil pipes in oil pump body, as shown
above, and securely tighten sleeve nuts 52.