Right after I start my car the oil pressure at 1000 RPM is almost exactly 60 psi. After it warms up it drops to a little under that. Im assuming this is too high and there is an obstruction. Ive been trying to fix it for a while now and it just happened on a drive back from an autocross with my overheating issues. Is it temperature related or a sender problem or what? Ive replaced the oil cooler, oil cooler lines, oil filter, and the oil pan (b/c the jackasses before me crossthreaded the drain plug and I had an extra pan). The car has been smoking a while but its from the turbo. PLEASE SOMONE HELP ME HERE I HAVE ANY PART THAT YOU SUGGEST IS BAD AND I CAN SWITCH ANYTHING.

 

The acceptable normal range for oil pressure is 43-86psig at 3000rpm with the everything at normal temperature and using 10W30 oil.
Normal behaviour of oil pressure(in a motor built by Mazda)is that the oil pressure should increase by ~5-10psig as the motor goes from cold to normal temperature(your owners manual tells you why).
If someone has modified the the lubricating system the above may not apply.

 

It is at 60 psi when cold at first start???

Normal temp when first start cold is around 30 psi, until the ecentric shaft valve opens, and then it should be 45-60 psi.

when it drops how much is "little under that"?

And BTW 10W30 that Six Rotors Suggests should only be used in temps between -10F and 80F. Never use that viscosity above 80F or engine damage and premature oil failure can occur.

 

it drops to about 40-45 psi at 1000 rpm and I use 20w50

my turbo is smoking but other than that I cant think of any possible obstructions

 

With the bypass plug from Mazdatrix, I'm running 60psi at idle, moving up to 75-80psi at full throttle. I wouldn't worry about it.

PaulC

 

yeah but Im pegging the pressure at like 5000 rpm

 

So you're hitting a very high pressure?

 

it could be the sender but I cant reach the damn thing to change it. Does it sound like a bad sender or an actually obstruction?

 

but yes, it is hitting high pressure

 

The oil pressure sensors on RX7 are, well, no darn good. Have you looked in the fsm and seen how the technician checks the oil pressure????? He does not use the factory gauge. He's using a mechanical gauge of the shop. At 3000 rpm the reading should be 64-78 psi, MEASURED WITH A MECHANICAL GAUGE.

As a side note: the sender can be pried apart and the cam in it adjusted to fit whatever pressure you wish it to read. You could get a mechanical reading and try adjusting the sender to that reading. Frankly its not worth doing. Just get a mechanical reading and compare it with your factory pressure and make mental adjustments in the future for the real reading. See Ted's site for how to do that.

 

I am confused,how can you not reach the oil sender?To answer I-Mark's question all my RX-7s have shown about 3.8 kg/cm2 on cold start(this translates to ~60psig).
As far as having an obstruction causing high pressure--where would it be?There are 3 relief valves in the system,oil pump,oil filter and eccentric shaft.

 

Id just think a failure of the sender would lead to lower readings than normal. This just happened one day on the interstate...about the same time as my high speed overheating problem came up. It seems that the new oil cooler fixed the overheating though. Its been kind of cool outside so its hard to tell.