ALPHA series engines worksHoP mAnuAL
33
2. Select the necessary cutting tool (B) and
assemble it to the handle (C).
3. Place the cutter over the mandrel and adjust the
three individual blades, using the Allen Key, if
necessary.
4. Rotate the tool in a clockwise direction until the
valve seat or recess finish is satisfactory.
2.28 tHe vALve guides
The guides are a press fit into the cylinder head and
must protrude by 11.75-12.25mm (0.462-0.482in)
above the top machined face of the cylinder head.
This dimension will be achieved when the depth
stop, 317-50108, is used with the guide removal
and replacement tool, 317-50033.
New valve guides and oil seals were first fitted on
the engines shown and all LPW(S)T4. The seals
now grip on the valve guides instead of the valve
stem, early seals are compatible with the current
valve guides but the current seals cannot be fitted
to early valve guides.
42 00396 LPW3
42 00850 LPW3
42 00687 LPW4
42 00770 LPWS4
2.28.1 valve guide and seal Part numbers
Later Type
Guide
751-10903
Seal
751-41701
Figure 2.28.1 Valve Guides and Seals
Later type
2.28.2 removing a valve guide
1. Remove the cylinder head.
2. Remove the valve.
3. Remove the valve stem oil seal from the guide.
4. Preferably place the cylinder head on its side in
a soft jawed vice.
5. Screw the correct mandrel (A) into the tool (B).
Figure 2.28.2 Valve Guide Tool and Depth Stop
Lister Petter Service Tool
317-50033
317-50108
317-50057
317-50075
6. Place the sleeve (C) onto the tool.
7. Fit the bevelled adaptor (D) into the sleeve (C)
and locate the bevel into the valve seat.
8. Locate the mandrel through the guide from the
valve seat side.
9. Screw the small threaded sleeve (E) onto the
mandrel at the valve rocker side.
10. Holding the sliding handle firmly to prevent
rotation, turn the double handled lever clockwise
until the guide is withdrawn through the head.
If it is found difficult to start moving the guides a
sharp tap with a copper hammer should break
the seal.
2.28.3 Refitting a Valve Guide
1. Fit the correct mandrel into the valve guide hole
from the valve rocker end.
2. Place the valve guide over the mandrel with the
counter bored end of the guide facing towards
the valve seats.
3. Place the depth stop (F) over the mandrel and
screw on the threaded sleeve (E).
4. Fit the tool complete with the bevelled adaptor
onto the mandrel at the valve seat side.
5. Hold the sliding handle firmly, to prevent it rotating,
and turn the double handled lever clockwise until
the depth stop prevents any further movement.
At this point the guide will protrude the correct
distance above the cylinder head.
6. Fit a new valve stem oil seal.
2.29 tHe CrAnkCAse door
The door is secured to the crankcase by studs,
nuts and setscrews. The door carries the fuel lift
pump, oil dipstick, oil filler and the oil filter.
To gain access to the sump the door must be
removed.