Vacuum Pump rebuild

Guide Number: SG0866 | Printer Friendly Version | View Safety Disclaimer

Skill Level

Level 3

Advanced task, requires high degree of mechanical/electrical experience. Recommend Park Tech to complete.


  • Tools needed
  • Dead blow hammer
  • Combination square ( use the small square as a small straight edge to adjust the wear plate clearance)
  • Small putty knife
  • 6 mm T Allen wrench
  • 3 mm T Allen wrench
  • 3/8 Torque wrench
  • 3/8 socket wrench
  • 1/2 deep socket
  • Small pick set
  • 1-1.25 pipe (to hold the impeller from turning)
  • slide hammer (possibly rent from a auto parts store)

Remove the vac pump from the machine and put on a work table

Pull the wear plate assemble off the pump

Removing the Impeller

Remove the spanner nut on the impeller using the spanner socket in the tool kit ,place a pipe in between the housing and the impeller housing to hold the impeller from turning when loosening the spanner nut. Use a channel lock pliers to remove the plug from the impeller it is held in by an oring (You may have to wiggle it to get it out).

Place a pipe in the impeller and the casting to prevent the impeller from turning

Once the stud and nut is pulled off,put on the impeller puller,you will also need to make a puller bar to pull off the impeller(secure the pump with a c clamp or set it on a piece of rubber so you can use the puller to jar the impeller loose)(Tap threaded holes in the impeller if the holes are clogged with mud, 10/32″ tap size)

Install the puller plate from the kit
Impeller is removed from the pump
You will need to make a puller to remove the impeller

Remove the 4-6 mm allen bolts and pull the pump casting off the motor. Use putty knives to pry off if pump casting is stuck to the motor. Do not damage the motor flange

Clean the flange of the motor

Install the new housing, Install the new carbon seal with the oring toward the new housing, (the carbon side of the seal mates with the carbon spring seal and this forms a water tight seal so the water does not get to the motor)

Install the new casting from the kit
This explains how the impeller is adjusted to the wear plate (similar to the grippers adjustment on the spindle )
Install the adjustment nut into the impeller

Install the new impeller and the carbon spring seal, Install the impeller adjusting nut into the impeller until it bottoms out , This nut pushes on the motor shaft and adjusts the impeller to the wear plate

Impeller installed on the motor shaft

Install the carbon seal so the oring is toward the pump housing and the carbon side out
Install the carbon spring seal on the impeller so the carbon is pointing toward the pump housing

Install the Jam nut or stud in the motor shaft. You will need use a straight edge and a .003 feeler gauge (this will adjust the clearance between the wear plate and the impeller fins. Place a straight edge on the inner rim of the pump and use the feeler gauge to verify that you have .003, if you do not have this clearance ,loosen the jam nut on the stud and then turn counterclockwise on the impeller nut to adjust the impeller in .(This is similar to the gripper setting on titan)

Install the new impeller on the motor shaft
Clearance adjustment to the wear plate (LX0055)
You will need to loosen the stud and turn the spanner nut clockwise to bring out the impeller(closer the the wear plate) and counterclockwise to bring the impeller further away from the wear plate.After the adjustment is made tighten the stud to about 15 ft lbs
You made need to make several attempts to achieve the .003 clearance
Install the stud in the arbor shaft

Use a straight edge and .003 feeler gauge to adjust the clearance

Install the new wear plate 70000135-2.

Clean the end housing thoroughly before installing the new wear plate
Install the new wear plate ,Verify that the reed valve is on the correctly
  • Install the 2 orings ,1 on the pump and the other on the pump end cap
  • Verify that the wear plate correctly fits into the groove on the pump casting and the end cap before tightening
  • Install the 5-6mm bolts on the end cap and tighten to 12 ft lbs (TIGHTEN IN A CROSS PATTERN ,SNUG ALL THE BOLTS FIRST THEN TORQUE)
  • Verify that the fan on the motor turns freely after the pump is fully assembled

You will have about a 1/8″ gap between the two case’s

Last updated: December 7, 2020

Need Some Help?

Contact Park Industries® Customer Service
800-785-3391 |


Prior to beginning installation, operation, or maintenance, you are advised to carefully read ALL instruction manuals and ALL safety materials and procedures provided with your equipment.

You are solely liable for the proper operation and maintenance of the equipment.

Park Industries® is not responsible for and expressly disclaims liability for any injuries (including death) or damage to the equipment or any other property as a result of improper operation or maintenance of the equipment, as well as failure to comply with the procedures set forth in the equipment’s instructional manual or any other safety materials and procedures. If you encounter any problems or difficulties, you are strongly encouraged to seek professional assistance.

Safety is our number one concern. Should you have any questions don’t hesitate to call our service team at 800-785-3391.