Oil pressure in multifuel

[TAKPAK]

I have an oil pressure problem....possibly too much? Here's the story; on cold startup, at fast idle (1000 RPM's) pressure is 60-70 PSI. As I start down the road, increased RPM's equates to increased oil pressure, sometimes to over 100 PSI. As the engine warms up to operating temps, pressure holds at around 60-70 PSI when cruising/light throttle. However, if I start giving her more power, even before the RPM's start to climb, such as pulling a hill, the oil pressure will spike to 90 to 110 PSI, sometimes pegging out at 120 before dropping back. Fully warmed up, at idle the pressure runs around 30-40 on the gage. I did replace both the gage and sending unit with a brand new one(s) when the old set quit working. Replaced it with the same one that was in there, 0-120 PSI. The engine was replaced in 1995, brand new engine, with the "D" turbo and the improved block and head (thick deck) so it's a good running engine. I also have no drips of oil anywhere. Engine is dry on the exterior, and nothing on the concrete below. I'm totally puzzled, as to why, on acceleration (more fuel/throttle) the pressure rises quickly, then settles back a bit, but still, if climbing a hill is running over 90 PSI. Never had this problem on any engine before. Ideas, please? One thought of mine is possibly plugged crankcase vent? Have not checked that possibility yet.

 

[gimpyrobb]

I woud pull the sending unit and install a mechanical gauge. When was the last time you changed fiters?

 

[Dipstick]

I had that problem too until I installed a "matched" pressure gauge and sender combination. There's a 60 psi sender for the 0-60 gauge and a 0-120 sender that works with the 0-120 pressure gauge. You have to make sure you have the correct pair. There is an oil pressure regulator on the block behind the turbocharger, but I doubt anyone would turn it up that high. Using 15W-30 Shell Rotella oil with spin on filters, my engine is at about 35 psi when it's warmed up. It's closer to 55 psi when cold. I've also found that a loose wire connection on the sender can send your oil pressure reading all over the place, except that it goes up one moment and down the next. Hope that helps.

 

[TAKPAK]

Gimpyrobb, that's my next step, to put a mechanical in and check it again. Regarding the filters, they are fairly new, only around 100 miles on them, and the oil as well. Changed it over to the Delo 400 15-40. Dipstick, I was thinking the sending unit too. It is a new one, with new gage, but I supposed that even though it's marked 120 PSI, it could have been mismarked, or just isn't working correctly.