Repairing the Oil Pump Base
by Lorne Goldman

Us Plus 8ers must now move over for the next generation. Our engines are no longer made and we must become more inventive and resourceful as parts become increasingly more scarce. Our brethren with older Morgans have shown us the way.

Here is one cute fix to keep handy;

It is a characteristic of the engine that the oil pump area becomes scored and pitted. Debris entering the oil system is picked up by the pump gears and carves grooves and holes on the soft aluminum oil pump base and in the gear recesses on the soft aluminum timing cover. New distributorless timing covers (1968-2000) are unavailable now (though the aftermarket Buick 215 suppliers in the US cast one that can be adapted).

Of course, the oiling system is a low pressure high volume one and perfect pressure is not a must but the more the surface of the oil pump base deteriorates, the lower the pressure falls. (The base holds the oil
filter, the pressure relief valve, the oil pressure sender and up to 2 other senders you may choose to add. It also holds the oil pump gears in position.

The gears are available and not TOO dear. For the moment, oil pumps bases can still be found..but the price is rising ominously. They are sold outside the UK for $385 USD each. They can be had within the UK for £95-155 ($175-300). All garages will simply replace them as a matter of course at great prejudice to your chrome budget.

There is a better much simpler idea. This comes from two Rover V8 engine preparers of note and is essentially where the new stock is coming from. Though there are detailed clearances necessary to the pump gears within the timing cover, none of these are effected the depth of the pump base face only its the smooth trueness of its surface.
 
With pump base in hand, place yourself before the television with (hopefully) a glass coffee table close. (Glass is normally the truest surface one can find.) Place a 8x11 sheet of 120 grit metal sand paper (emery) on the table. While watching your favorite entertainment, sand the inner face of the pump against the table/paper until the gouges and grooves disappear. Arise 385 dollars richer! Pick up a dozen for £3 from the local break-up shop and you can create your own cottage industry! Here is a before-and-after image.

(NOTE: When reinstalling the pump, pack it with vaseline to insure it can prime itself.)