18 684025
Replacing the Bearings
1. Relieve the Pressure. Refer to Figure 6 and Figure 7.
WARNING
To reduce the risk of serious injury whenever you are
instructed to relieve pressure, always follow the Pressure
Relief Procedure on page 11.
2. With the bleeder type main air valve (1) turned off,
remove the twenty hex bolts (16) with a 13mm wrench
or socket and then remove the four sheet metal
covers (17) from the front and back of the
proportioner. The left rear cover may contain a sensor
attached to a cable. Do not remove the sensor, but
carefully set the cover to the side without strainin
or
dama
in
the sensor or cable. The (4) four main
bearings (21) are now exposed.
3. Remove the thumb screws (14) and the two
uards
(15) from the sides of the proportioner.
4. Usin
an adjustable wrench (or hammer and punch),
unscrew the couplin
nuts (10, 11, 12) from each of
the rod adapters (13) on the two displacement pumps
and the air motor. Do not lose or drop the couplin
collars (12). See Fig. 6.
5. The left rear bearin
shaft has a ma
net stuck on its
end. Remove the ma
net and put it in a safe place.
Use a snap rin
pliers to remove the four snap rin
s
(22) from the shafts and remove the retainin
washers.
6. You should now be able to slide the bearin
s (21) off
of the shaft ends.
7. Replace the bearin
s only with identical Graco
replacement parts. Pack the bearin
s in Industrial
Grade 1, Heavy Duty, Extreme Pressure, Lithium
Soap Grease, Graco Part Number 110293 or
equivalent.
8. Re-install the new bearin
s (21) onto the shafts.
Doin
so may require sli
htly shiftin
the shaft
assembly which may have dropped durin
bearin
removal.
9. Re-install the four retainin
washers and their snap
rings (22).
10. Replace the ma
net onto the end of the left rear
bearing shaft.
11. Make sure the couplin
nuts (10, 11, 12) and the
couplin
collars (12) are in place on all three rod
adapters.
12. Screw all three (3) couplin
nuts (10, 11, 12) onto
the rod adapters (13) loosely. Hold each rod
adapters flats with a wrench to keep it from turnin
.
Use an adjustable wrench to ti
hten the couplin
nuts. Torque to 196–210 N.m ft-lb).
13. Replace the covers (17) and the bolts (16).
14. Replace the two
uards (15) and the thumb screws
(14) onto the sides of the proportioner.
15. Turn on the air supply. Follow the procedure for
startin
the pump on pa
e (11). Run the pump
slowly at first to ensure proper operation.
Bearing Inset
Fig. 7
