Hello Bill:
This kind of work was always considered basic maintenance on LBCs. I can't
put my hand on it at the moment, but I believe my 1967 Owners Handbook
states that rod bearings are to be replaced at 30,000 mile intervals and
that mains want attention at 50 k. I could be wrong about the numbers but
the intent is clear. LBC engines were built with very stout crankshafts.
Crankshaft turning was not necessary as long as bearings were replaced on
time. Similarly, rings were to be replaced rather often but again without
reboring.
Most LBCs of the period also called for "de-coking" at 10,000 miles and
other very short periods for similar maintenance. Some of my late '40s
cars called for lubrication at intervals as brief as 250 miles for some
items. All of this maintenance was considered basic work for the owner.
Remember the old maxim, "Fix of Saturday and cruise on Sunday".
>I pose this question based on my experience. I have now owned two B series
>engines with around 70,000 miles on them. They both had low oil pressure.
>Upon dissassembly, both had all of the babbit worn away from their rod
>bearing exposing the underlying copper layer. On the B, replacing the rod
>bearing fixed the oil pressure problems and, based on what I have found, I
>fully expect the same results with my A.
>
>Replacing the rod bearings is not that tough. Maybe we should start
>thinking about them as 50,000 mile items and just replacing them as a
>matter of course. Expecially when you consider the havoc raised at the top
>end of the engine with low oil pressure and the cost of an MGA crankshaft
>nowadays.
>
>Just a thought.
>
>Regards,
>Bill Eastman
>61 MGA
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