Howdy?,
Over the past few weeks I`v be fitting a "new" second hand A15 to my 1000 sedan,
I think the motor is fairly good (maybe HM rebuild as it has HM stamped into the piston crowns).
When I got it fired up it sounded pretty good too (apart from some tappet noise)
However I did note that the oil pressure gauge (mechanical) was reading only halfway around the gauge (40psi) compared with three quarters (70 psi) with the old motor and pump.
I put this lower oil pressure down to "thinner" oil (no more BP corse+)
Today I decided to pull the oil pump out of the old motor and give it a go, low and behold three quarters around the gauge ( same as old motor).
Although the two pumps initally appeared similar the were a few slight differences the "old" pump has a "4" cast on the side the "new" has "14" cast on it, The "old" pump has "so4" stampped into it and the "new" pump has "R19" stampped into it,
But I think the major visual difference id that the "old" pumps drive gear extends about 5mm longer then the "new" also the pressure sender outlet is longer on the "old" one.

What should be the std. oil pressure be? and is there different models of oil pump for model A-series?

Cheers,


G O T H E D A T !!

Yes they are all the same, except for the Nismo pump.

70 psi is too high. Are you using the same mechanical gauge?

60-70 psi when cold is more than alright. all my cars have run around this when cold then come back down to like 50-60 psi when warm depending on the oil ... its probably just a worn pump so just buy a new one or keep the old one in there

70 psi is out of specification:
Quote:

But 70 psi won't hurt anything.

[Edit] A15 oil pressure specificatin at idle is "More than 11 psi" and at 3000 RPM "54-74 psi". So there is a difference between A12 and A15 oil pump -- the regulator spring is a little different.

Cheers,
The gauge is the same unit used on the "old" motor.

However I never rely on the numerical reading as being gospel I only use it as a reference (1/4, 1/2, 3/4).
In my old motor ("old" pump) this gauge always read 2/3 - 3/4 from start-up, and close to off the scale at full noise.

Could have this pump been modified to suit its ex-drag racing set-up? (The previous owner of the "old" motor used to run 8000 rpm at 30psi boost on avgas)

Could there be potential engine damage due to exesive oil pressure?

Im thinking of running an oil cooler, will this effect oil pressure?


Cheers,



G O T H E D A T !!

Excessive oil pressure, long term is not a good thing for your engine. I would be chasing higher oil volume figures instead. Its better to have more oil for given time period.

If you do the L pump mod, should you open up some of the oil ports to reduce presure?