Waters Xevo TQ-S Operator's, Overview And Maintenance Manual page 125

3. Use the 10-mm wrench to fit and tighten the nut that secures the oil
demister element to the exhaust flange.
4. Ensure that the inscription "TOP" is at the top of the oil demister
element, and, using both hands, carefully fit the oil demister element
and exhaust flange to the roughing pump.
5. Use the 6-mm Allen wrench to fit the 4 bolts securing the exhaust flange
to the roughing pump.
Tighten the bolts securing the source exhaust flange to the
Important:
roughing pump sequentially and by small increments until they are all
fully tight.
Maintaining the Oerlikon Leybold oil-filled roughing pumps
1 mm exposed thread after tightening
February 28, 2014, 715002212 Rev. C
TP02686
125