Idle Oil Pressure?

[bomilcar]

I just put in a ISSPRO electric oil pressure gauge. What pressure should I see at idle? I find in the book it should be 28psi at 2000rpm but I can not find an idle number.

On a different issue. Has anyone replaced the AC pusher fan with an upgraded version? Not much room for larger but anyone try?
Thanks

[Hans]

28psi at 2000rpm? Excellent, I thought mine was low.

Mine idles at around 15psi or so.

-Hans

[mffoster]

The oil pressure on these things is almost scarily low. I believe that my factory manual basically called out slightly more than 10 psi per 1000rpm. At idle you should be between 10 and 15 psi. I've had a 94 since new, and put in VDO guages within about 6 months of the purchase. I was pretty nervous originally, but that just seems to be the way these work, and your's sounds fine. You can get a bit more pressure if you take off the sandwich plate to the oil filter and use a carbide to open up and smooth the machined passages. Also, if you switch to something like a Mocal adapter plate with a thermostat to bypass the oil cooler when cold you'll see pressure on the guage much more quickly on a cold start.

If you're really interested I could go look up the exact pressure specs in the factory manual.

Regards,

Mike F
Concord, NH

[bomilcar]

Thanks guys. Changed oil and filter; 20 50 with a K&N filter and I am getting 30+ psi at 2000 rpm and right arount 10 at idle 750rpm. 10 gives me pause but I guess it is OK. Sure is higher after I dumped the syntec and put in the 20 50. Wha tis going to be interesting is in the heat of the summer 100+ degrees.
Thanks

[ScottYates]

Wouldn't changing the bypass spring to a higher weight spring force the pressure up by not allowing oil to bypass the circuit? I am also curious.

[robisonservice]

The idle oil pressure is very much dependent upon the combination of bearing wear and oil viscosity. An older motor with Mobil 1 0-40 might have 2-5psi at idle. The same motor, with dino 20-50, might have 10-12 psi.

When 0-40 oil was introduced in 1998, Mercedes had to drop the oil pressure gauges from its cars because the low numbers people saw at idle scared them, and caused service problems.