MG Magnette KA Instruction Manual page 110

Removing the Dynamo. In order t o obtain easy access t o the dynamo f o r
removal
it
is advisable t o take off the radiator. Remove the lock nuts and nuts from
t h e radiator bolts carried through the engine nose piece extension, and the bolts
retaining the yokes o f the bonnet tie-rods. Remove water return pipe from
cylinder head, and loosen clips holding bottom water hose.
N.B.-It is unnecessary t o interfere w i t h any o f the oiling system t o remove
dynamo.
Between the projecting portion o f the cylinder head and the t o p of t h e dynamo
w i l l be found a circular flexible coupling. Remove the nuts on each o f the four
coupling bolts i n turn, leaving the bolts in position, so that t h e coupling can be
rotated by use o f the starting handle t o bring each bolt into a position where the
n u t may easily be reached.
Having removed all four nuts, take off the valve gear cover and t u r n the engine
by the starting handle until the timing marks on the spiral bevel gears coincide.
These will bring t h e driving yoke on the cylinder head across the engine, and t h e
driving yoke on the dynamo parallel t o the engine centre line. The bolts themselves
may now be withdrawn, care being taken not t o lose t h e distance washers, which
must be replaced in the same position. Removal o f t h e bolts enables the flexible
coupling t o be withdrawn.
Detach the t w o cables on t h e distributor side of the dynamo, noting f r o m which
terminal they are removed.
N o w unscrew the four set screws which attach t h e dynamo t o its platform at
t h e f r o n t of the engine, thus releasing t h e dynamo. Lift t h e dynamo approximately
a quarter o f an inch and
tilt
it
towards the near-side of the car until the driving yoke
on t h e dynamo is just clear o f that o n the cylinder head. The dynamo can then
be tilted forwards and easily withdrawn.
Replacement of t h e dynamo is effected in t h e reverse way, but it is necessary
t o make sure that the engine timing has not been disturbed while the dynamo was
removed. Removal of t h e rectangular cover-plate in the clutch housing should
reveal the timing mark on the flywheel for Nos. I and 6 cylinders, exactly i n the
centre o f the opening. Place the brass packing shims which
fit
under the dynamo
base i n position on the dynamo platform, making sure that you replace the same
number that you t o o k off. I f for any reason the dynamo is replaced by another,
it
may be necessary t o readjust the mesh o f t h e driving gears t o obtain silent running
by suitable selection o f the packing shims used. Turn t h e dynamo spindle until t h e
timing mark on the dynamo drive gear coincides w i t h the centre line o f t h e dynamo
and is at the rear-that is, ready for engagement w i t h t h e correspondingly marked
teeth o f the drive gear on t h e crankshaft. The holes in the dynamo coup!ing yoke
w i l l then be parallel w i t h t h e engine centre line. Tilting the dynamo towards the
near-side o f the car and holding the dynamo coupling yoke in this position, insert
the drive gear i n t o t h e opening of the dynamo platform and swing t h e dynamo back,
wards and downwards i n t o position. The gears can be felt t o be meshing properly
i f t h e coupling is slightly oscillated as t h e dynamo is replaced, but d o not overdo
t h e oscillations o r you may engage t h e wrong teeth.
Page Ninety-two