AJS 350 1954, Maintenance Manual And Instruction Book, Page: 38 / 96

Remove
Lower end of rocker box oil feed pipe by unscrewing union nut.
Both oil pump end caps.
Oil pump plunger guide screw with pin. (See Illustration 12.)
Oil pump plunger, by pushing at front and extracting from rear end of its housing.
Replace by :
Reversing above procedure.
NOTE—Remember there is a paper washer under each oil pump end cap and, when
fitting a new paper washer to the front cap, ensure the oil passage in the
front cap is not obstructed by the paper washer.
Important
Make certain that the guide screw pin is correctly located in its groove (cut in
the plunger) before tightening down. NOTE :—The guide screw pin is in-
serted in the screw relieved end first. Do not revolve the engine until quite
certain that the guide screw pin is properly located, otherwise damage is
inevitable.
OVERSIZE PARTS AN D RE-BORING CYLINDER BARREL
Pistons and rings, .020" and .040" larger than standard, are available. These degrees
of oversize make it essential for the cylinder barrel to be re-bored to accommodate them.
We can provide that service at prices quoted in the Spares List.
On the 350 c.c, the cylinder standard bore is 2.7187 ± .0005". The 500 c.c cylinder
standard bore is 3.250 ± .0005".
When the wear at the top of the barrel reaches .008" the barrel should be bored out
.020" oversize and a new oversize piston and rings fitted.
Crankpin rollers .001" larger than standard can be supplied. We recommend only
skilled mechanics should fit these because it is almost general that the big-end journals
and sleeves require " lapping " to ensure a correct fit.
REMOVING SPARKING PLUG
Always exercise the greatest care to avoid thread seizure when removing a sparking
plug.
If any resistance is felt, apply paraffin. Before replacing plug, it is desirable to
coat the thread with " O i l D a g " or Graphite paste. This will guard against seizure
upon subsequent removal.
WHEN IN DOUBT REGARDING THE NAMES AND PART
NUMBERS OF THE PARTS YOU REQUIRE, PLEASE SEND
THE OLD PARTS TO SERVE AS PATTERNS.
TO REMOVE AND REPLACE THE OIL PUMP PLUNGER
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