Lycoming TEO-540-C1A Maintenance Manual page 272

P. To measure the dry tappet clearance:
Figure 38
Valve Clearance Gage
(ST-23)
(1) Push in on the push rod end of the valve rocker.
(2) Use a Valve Clearance Gage (ST-23) (Figure 38) to measure the distance between the end
of the valve rocker assembly and the valve stem cap (Figures 39 and 40).
(a) Insert the 0.028 end of the Valve Clearance Gage (ST-23) between the valve rocker
assembly and the valve stem cap. If it cannot be inserted, remove the current push rod
and use a shorter pushrod.
(b) Try to insert the 0.080 end of the Valve Clearance Gage (ST-23) between the valve
rocker assembly and the valve stem cap. If it can be inserted, remove the current push
rod and use a longer pushrod.
(3) The distance must be between 0.028 and 0.080 in. (0.711 to 2.032 mm).
NOTICE: If the clearance is not within the prescribed limit, insert a longer or shorter
Q. Recheck the valve rocker clearance on all cylinders and make any adjustments as required.
R. Lubricate rocker contact surfaces (Figure 41) with Modoc
72-30
Page 242
Figure 39
Dry Tappet Clearance
push rod to obtain the correct clearance. Refer to the TEO-540-C1A
Illustrated Parts Catalog for push rod information.
Figure 41
Valve Rocker Lubrication
TEO-540-C1A Engine Maintenance Manual
TEO-540-C1A Engine Maintenance Manual
Measuring Dry Tappet
®
Oil 175.
© 2018 Avco Corporation. All Rights Reserved
Figure 40
Clearance
November 2018