Try switching to a straight 30 weight oil as a temporary method of raising the oil pressure, with possibly an additive like Lucas oil treatment also. It's not a permanent fix, sort of a "band-aid on a brain tumor" type of thing, but it might avoid a catastrophic engine failure until you can get around to a complete overhaul.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!