background image

TB 08-03

RevA Apr.2021

CAM LEVER ADJUSTMENT PROCEDURE

LM 20” MANHOLE ASSEMBLY

WITH ADJUSTABLE CAMS

STEP 1:  See Figure 1.  After cover (1) is installed on weld ring (2) with hinge pin (3), position 

cam levers (4) on cover and close cam at each hold-down position.  Minimal friction 
resistance between bottom of cam and top of wear plate (5) should be evident.  See 
(FIGURE 1)

STEP 2:  Insure upper pivot pin is centered between cam lever “ears”.  Use socket wrench to 

tighten cam adjustment bolt (6) on top until gasket and weld rings top surface make 
contact at each of the six cam locations

STEP 3:  To insure a good peripheral sea tighten each cam adjustment bolt (6) shown in 

FIGURE 1 to 13 lbs-ft (up to 16 lbs-ft).  Cam tightening order should be done in a star 
pattern which is shown in FIGURE 2.  Tighten starting with cam number 1 and move 
sequentially to cam number 6.

NOTE (1):  Gaskets should be checked periodically for cuts or accumulation of  

product and could result in sealing problems.  Replace all damaged 
gaskets.

NOTE (2):  Cam levers and wear plates need to be inspected for excessive wear in 

the area where they make contact.  If the cam lever opens easily with 
minimal resistance, replace the worn components.

Reviews: