Sump And Oil Pump Strainer; Main And Big-End Bearings - MG MGA Twin Cam Workshop Manual

Disconnect the tachometer drive cable from the rear of the cylinder block. Release the exhaust pipes
from the exhaust manifolds and from the steady bracket on the engine rear mounting plate.
Slacken the exhaust pipe clamp bolt at the joint between the front and rear pipes and remove the front
pipe from the vehicle.
Disconnect the flexible oil gauge pipe from the union at the rear of the cylinder block on the right-hand
side. Disconnect the cables from the dynamo, ignition coil, distributor, and starter motor.
Remove the bolts from the clamps at the base and top of the steering-column and the nut, bolt, and
spring washer from the rear end of the steering-column universal joint. Withdraw the steering-column.
Remove the dipper switch mounting bracket. Release the petrol pipe clip from the steering-column
dust seal retainer plate. Withdraw the throttle cable.
Remove the nine set screws and washers from the toe board support plate and remove the plate.
Remove the four bolts, nuts, and spring washers securing the mounting plates on each side of the
engine.
Place a rope sling around the power unit and attach the lifting tackle. Arrange the sling so that the unit
may be lifted slightly and moved forward and finally lifted from the frame at a sharp angle with the
front considerably higher than the rear.
Take the weight of the unit and remove the nut, bolt, and spring washer to release the gearbox from
the mounting bracket on the frame cross-member.
The power unit is now free to be manoeuvred from the chassis.
Replacement
Replacement is a reversal of these instructions. Refill the engine and gearbox with oil to Ref. A
(Section P).
A.25 SUMP AND OIL PUMP STRAINER
Removal
Drain the oil from the engine sump.
Remove the bolts and withdraw the sump from the crankcase.
To remove the oil strainer, remove the three bolts securing it to the pump cover.
Clean out the sump and strainer with paraffin (kerosene) and a stiff brush; never use rag.
Replacement
When refitting the sump to the engine give particular attention to the gasket. If the gasket is in good
condition and has not been damaged during removal of the sump it may be used again, but it is
always advisable to fit a new one. Before fitting a new gasket remove all traces of the old one from
the sump and crankcase faces. Smear the face of the crankcase joint with grease and fit the gasket.
Lift the sump into position on the crankcase, insert the securing bolts, and tighten them evenly.
A.26 MAIN AND BIG-END BEARINGS
Unless the bearing journals are badly worn the big-end bearings may be renewed without removing
the crankshaft. To renew the main bearings, it is necessary to withdraw the crankshaft as detailed in
Section A.33. Liners are used both for the main and the big-end bearings, which are of the shimless
type and therefore non-adjustable.
Big-end bearings
Drain the engine oil and remove the sump as in Section A.25.
As the bearings are of the shimless type it is essential that no attempt should be made to adjust
bearings which are worn. Always fit new bearings in place of worn parts. If the crankshaft journals are
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