Royal Enfield 500 TWIN 1949 Workshop Maintenance Manual page 24

ROYAL ENFIELD WORKSHOP MANUAL
temporarily and tightening the nut whilst the
crankcase is still hot.
7. Pump Worm Locknut
The pump worm is held in position in the
end of the crankshaft by a steel nut which is
permanently fixed in the crankshaft and should
not be removed.
The nut is fitted in a recess and locked by
means of a long peg which in turn is held by a
grub screw in the timing side crank web.
If it is necessary to re-fit the nut, assemble
the timing sprocket with the pump worm and
nut in the crankshaft while out of the crankcase
and tighten it up.
By means of a long drill through the hole in
the crankshaft web, countersink the nut to about
1/8 in. Insert the locking rod and grub screw.
Remove the pump worm and sprocket and
re-assemble after the shaft has been fitted in the
crankcase.
500 TWIN 1953
Section D1 Page 3