Perkins — To Replace Vacuum Fan Impeller
Repair & overhaul
From a Perkins service manual — check it applies to your exact model before use.
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Before you start
- Raised hopper may fall. Engage hopper support bar
- Use blue loctite 242 on shaft threads
Procedure
- Dump the machine debris hopper and set the parking brake.
- Raise the hopper, engage the prop arm, and lower the hopper.
- Shut off the engine; open engine cover and side door.
- Remove the vacuum hose and bracket from the front of the vacuum fan housing.
- Disconnect the wires to the Thermo Sentry.
- Disconnect and plug the three hydraulic hoses at the vacuum fan motor.
- Remove two M10 hex screws, washers and rubber isolators holding fan housing to the frame.
- Remove solenoid valve mounting bracket and isolator from top of housing.
- Tip the vacuum fan assembly forward and remove it from the machine.
- Remove the six 0.31 in hex screws holding the front housing to the rear housing.
- Remove the crown nut from the impeller shaft; slide the impeller off (save key and shims).
- Turn housing over; reinstall shims, key, impeller, and crown nut; tighten crown nut to 34--47 Nm.
- Reinstall front housing; tighten 0.31 in hex screws to 22--27 Nm.
- Reinstall assembly and hoses; reconnect electrical harness to the Thermo Sentry.
Specs & values
- Crown nut 34--47 Nm (25--35 FridayParts $25.27 ft lb)
- 0.31 in hex screws 22--27 Amazon eBay Nm (16--20 Amazon eBay FridayParts $14.38 ft lb)
- M10 hex screws 37--48 Nm (26--34 ft lb)
Source: Perkins service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.