Page 84 - Vauxhall 20-60 H.P. (R Type) Chassis Shop Manual

VAUXHALL 20-60 SHOP MANUAL

– Remove cylinder head holding down nuts ( 16 in all ). – Torque 52lbs/ft
– Remove tappet cover plates. Gently raise cylinder head and remove each
valve rocker operating push rod when the cylinder head has been raised
about an inch. A hardened steel ball is located at either end of each push
rod. Mark each push rod as it is removed and replace in its original position.
Finally, complete removal of cylinder head.

INSPECTION

SECTION – Remove valves and check seatings ( Section 408 ). Clean all carbon
405 deposit from combustion chambers. Examine cylinder head gasket and
replace if damaged.

TO REPLACE

SECTION Reassemble valves ( Section 408 ). To replace cylinder head, reverse operations
406 given in ( Section 404 ). Use a little jointing medium on each side of the gasket

and tighten the holding down nuts in the order laid down in Fig. 24. Re-tighten
the nuts again after the car has run some distance when the gasket has had a
chance to settle down again after disturbance.

ENGINE — TO DECARBONISE

SECTION – Remove cylinder head and gasket ( Section 404 ) .
407 – Turn engine over by hand and remove the carbon from the top of each

piston as it reaches the top of its stroke, carefully cleaning all particles
of carbon away as each piston is cleaned. Remove all carbon from the
cylinder head combustion chambers and clean gasket.

Reassemble cylinder head ( Section 406 ).

VALVES — TO REMOVE AND CHECK SEATINGS

SECTION – Remove cylinder head ( Section 404 ) .
408
– Place a suitable piece of wood under each pair of valves as the springs are
removed.

Using a suitable valve spring compressor depress each valve spring in turn
and remove the split collars from beneath the valve collar. The valve springs
can then be removed and the valves pushed out.

– Grind the valves in by the usual method. It is important that each
valve should be checked for correct seating after regrinding. To do
this, thoroughly clean grinding compound from valve and valve seat in
cylinder head. Smear marking lightly on the valve and replace in cylinder
head, but do not twist on seat. Then by using a heavy screw driver, apply
pressure to the valve head and turn about J’ only. If the valve is seating
correctly, a complete reproduction of the valve seat will be found in the
cylinder head when the valve is removed.

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