Gast 0740 Series Oilless Vacuum Pumps and Comressors - Manual (Page 5)

Disassembly
1. Remove the shroud and fan.
2. Use a wheel puller to remove the dead-end plate
and bearing from the pump body. Note the
direction of the bevel edge on the vane. Do not
damage the dowel pins between the end plate and
the body. Save the bearing spacer on the dead-
end of the shaft for reassembly. Remove the
snap ring from the end plate. Save the snap ring,
belleville springs and washer for reassembly.
3. Remove the bearing from the dead-end plate.
4. Check the exposed surfaces of the rotor, body, and
end plate for scoring. If you find no scoring, you can
perform a Minor Rebuild to replace only the vanes
and the dead-end bearing. If you find severe
damage, perform the Major Rebuild.
Minor Rebuild
5. Install the new vanes supplied with the kit. Be
careful to face the vane bevels in the proper
direction (as noted in step 2).
6. Place end plate over the shaft with dowel pins
aligned. Place bearing spacer on dead end of
shaft. Place the new bearing in its bore in the
dead end plate. Be careful to press only on the
inner bearing race.
7. Install and tighten the pump body bolts, install the
belleville springs with the washer between them
and the snap ring.
5
We have Gast Authorized Repair Facilities throughout the world. For the most up-to-date list-
ing, contact one of our sales offices below:
Major Rebuild
5. Remove the drive end cap. Use a wheel puller to
remove the drive-end plate and bearing from the
body. Do not remove or damage the dowel pins
in the body. Save the bearing spacer and end plate
gasket for reassembly.
6. Place one shoulder ring in its seat in the drive-end
plate, then place one of the new bearings in the
seat. Using an arbor press, press the bearing onto
the shaft. Be careful to press only on the inner
bearing race. Tighten the pump body bolts.
7. Install the new vanes supplied with the kit. Be
careful to face the vane bevels in the proper
direction (as noted in step 2).
8. Perform step #6 from Minor Rebuild.
9. Install the belleville springs with the washer between
them and the snap ring. Install and tighten the
pump body bolts.
10. Apply a thread-lock adhesive and start the drive-
end cap into its thread in the drive-end plate, but
do not tighten it.
11. Place a dial indicator against the dead-end of the
shaft to measure axial movement.Tighten the drive-
end cap until the indicator shows:
001” (for models 0240, 0440, 0740) and .002”
(for models 1550, 3040) of shaft movement
against the belleville springs.
12. Clean and reinstall filter(s).
Gast Manufacturing, Inc.
2300 S. Highway M139
Benton Harbor, MI, 49022
Ph: 269/926-6171
FAX: 269/925-8288
www.gastmfg.com
Gast Hong Kong
Unit 12, 21/F, Block B
New Trade Plaza
6, On Ping Street, Shatin
N. T. Hong Kong
Ph: (852) 2690 1066
Fax: (852) 2690 1012
www.gasthk.com
Gast Group Limited,
United Kingdom
Unit 11, The I O Centre
Nash Road
Redditch, B98 7AS
United Kingdom
ph: +44 (0) 1527 504040
Fax: +44 (0) 1527 525262
www.gastmfg.com