oil pressure

Oil Pressure

Low oil pressure is a curse that leads to the
sometimes unnecessary rebuild of our engines. Oil
pressure problems can come from several areas. Bad oil pump - main bearings - rod bearings - pressure relief
valve - rocker shaft .
The easy check is the pressure relief valve. On MGA
& MGB engines it is located on the left rear of the
engine above the oil pan. It consists of a valve, a
spring, and a cap. The purpose of the valve is to
release excess oil pressire back into the pan. However
if the spring gets weak, it will allow to much
pressure to escape. Sometimes replacing a weak spring will fix the problem.
The bearings are susceptible to wear and thus the
loss of oil pressure. The main & rod bearings are more
difficult to access and if they are the problem would
probably entail an engine rebuild. However the rocker
shaft is very rebuildable without the total rebuild.
Unbolt the 8 bolts holding the shaft. With the shaft
off check for wear by moving the rockers side to side
on the shaft. Excessive movement means the shaft
should be replaced and the bearings in the rockers
replaced & honed. With everything back together
hopefully you won’t find a need to rebuild the
complete engine.