Not engine specific but I think that with the age of many Morgans then some faults will occur. Age as much as mileage influence the condition.
At some stage the exposed wiring needs a clean up or replacement. I found this on my 2002 car. The front light wiring is exposed to water from the wheels. Bullet connectors are not waterproof and deteriorate. I replaced mine with new spades and sealed them with shrink sleeve.
Same applies to rubber components. I did a front to back replacement/flush of the fuel system on my 1993 18 year old 4/4 when fitting a new fuel pump. Included extra filter protection for the new pump, new flexi pipes etc.
Deteriorating electrical contacts is a fairly common fault inducer. Earth connections especially!
