[KOG]

First look to the sending unit, those are known failure spots on about any engine.

 

[valiant67]

Yep, I agree the sending unit is probably the cause. Especially if there are no odd engine noises accompanying the oil light.

 

[Rickorino]

Every time I had one of those sending units fail, they also leaked oil. They can leak enough to lose much of the oil, so you may want to also watch for that. If the engine is noisy when the oil light flickers, shut the engine off and have the pressure checked.