Place a machinist's level (Starrett 98-6) on top of the piston cap, rotating the cap, and adjusting the feet until level.
Adjust the bubble level so the bubble is centered.
Final Adjustment of Bubble Level
1. Tighten the SHC screws to slightly compress the belleville spring.
2. Adjust the SHC screws to center the bubble of the bubble level within the red circle.
3. Tighten the set screws to immobilize the bubble level.
4. Verify that the bubble remains centered after tightening the set screws. The set screws can be used to make small movements of the bubble. If the bubble does not remain centered, loosen the set screws and SHC screws and repeat steps 2 through 4
If just the bubble level has been broken or needs replaced in any PG700/PG9000 models it can be replaced with this kit:
PN: 3126977
Description: 401674,KIT,BUB LVL,PG7600/AMH100
If need the full bubble level assembly including the adapter that goes directly into the PG7000/PG9000 base, can replace it with this kit ( (includes everything in part 3126977 above, plus the adapter):
PN: 3120139
Description: 402068,KIT,BUB LVL,PG71/72/73XX
Note: If you have a PG base and an AMH (automated mass handler) you likely already have a spare bubble level as one is shipped with each component and only use one or the other. New bubble levels will need adjusted per the above procedure.