Gearbox Seal Replacement for B24 or B31 Gearbox
A Step-by-Step Guide to Replacing Broken Seals on a Pressure Washer Gearbox Assembly
Need a new gearbox?
- Long #4 Allen wrench
- #6 Allen wrench
- 19mm wrench
- (4) 8x1.25x30mm grade 8 bolts (1/2" head)
- Red thread lock
Step 1: Draining the Gearbox Using a 19mm wrench, locate the drain plug on the gearbox and carefully remove it to drain the gearbox completely. Ensure that all the oil has been drained before proceeding.
Step 2: Separating the Gearbox from the Case/Assembly Identify the four #6 allen head bolts that are facing the engine side of the gearbox. Use the #6 Allen wrench to remove these bolts, separating the gearbox from the case/assembly.
Step 3: Removing the Gear After separating the gearbox, you'll find a 4" gear. Remove this gear by unscrewing the long #4 Allen bolt on the set screw.
Step 4: Replacing the Seals With the gear removed, you'll notice four more #6 allen/hex bolts coming out of the flange. Flip the gearbox upside down and replace the 2 3/8" O-ring. Remove the old O-ring and the four #6 allen/hex bolts, discarding them.
Step 5: Reattaching the Gearbox Flange Caution: Do not remove the pump shaft flange. After replacing the old O-ring, reattach the gearbox flange to the pump, using new grade 8 M8 bolts. Reuse the four washers from the old bolts.
Step 6: Securing the Bolts and Reassembling Using three drops of red thread locker on each bolt, install the new bolts in the flange. Hand-tighten the torque to 18ft-lb. Slip the gear back onto the shaft and tighten the gear set screw to 3ft-lb. Proceed to reassemble the gearbox case using the four #6 allen/hex bolts.
Step 7: Refilling the Gearbox Refill the gearbox with 80w90 gear oil until the level is slightly above the red dot indicated on the sight glass.
By following these step-by-step instructions, you can successfully replace the broken seals on your General Pump B24 and B31 Gearbox assembly. Remember to exercise caution and follow safety guidelines throughout the process.