Cylinder Head Decarbonise - Reliant ROBIN 850 Workshop Manual

The engine Section F
3 Remove oil filler cap from rocker cover
unscrew retaining screw and lift air cleaner body
from base plate.
4 Disconnect throttle and choke cables at
carbu rettor.
5 Unscrew two
1
5
6
UNF self locking nuts,
complete with fibre washers and remove rocker
cover.
6 Remove two
1
5
6
UNF nuts and lockwashers
and lift carburettor from inlet manifold studs.
7 Disconnect temperature gauge sender unit
lead at thermostat housing .
8 Drain radiator and disconnect top hose and
by-pass hose from thermostat housing.
9 Disconnect heater hose from adaptor at rear
of cylinder head.
10 Disconnect cool air hose from heater and
engine bulkhead .
11 Disconnect high and low tension leads at
Figure 13 Cylinder head nut tightening
sequence
9
2 Remove valves from cylinder head using
valve spring compression tool keeping in correct
order. Retain valve springs, covers, cups and
cotters for inspection.
coil. 3 If valve guides are worn remove them using
Tool No. RT7478 (see Figu re 14).
12 Disconnect spark plug leads and remove
distributor cap.
13 Unscrew
i
UNC bolt, complete with
plain washer and lockwasher securing
distributor. Do not disturb clamping bolt
securing distributor unless the ignition timing is
to be adjusted on reassembly.
14 Remove twelve
i
UNF and three -,\ UNF
nuts and washers from cylinder head.
1 5 Withdraw the push rods keeping them in
their correct order.
16 Carefully lift cylinder head from the
cylinder block.
17 Replace in reverse order after cleaning the
cylinder head and block faces and fitting a new
gasket. To ensure a good seal when replacing
head, smear grease around the metal edges of
the gasket bore eyelets. Tighten the cylinder head
nuts to a torque of 3·46kg m (251 b ft) in the
sequence shown in Figure 13. The three
-,\ UN F nuts must be fitted to the spark plug
side of the cylinder head and tightened to a
torque of 2·07kg m (151b ft).
Operation 10 - Cylinder head
decarbonise (with cylinder head
removed)
1 Unscrew the four spark plugs.
4 Use a piece of sharpened wood to break up
the carbon deposits on the piston faces of the
cylinder head and then polish with wire wool.
5 Reface all valves or replace if badly burnt or
the stems are unduly worn.
6 Replace valve guides in cylinder head using
Tool No. RT7478 (see Figure 14) .
Figure 14 Valve guide removal and
replacement
1 Valve gu1de removal
2 Valve guide replacement
3 Valve guide protection sleeve