: High oil pressure



geoz3
05-17-09, 07:43 AM
What should the proper oil pressure reading be a start up? I hae a 94 N* in a kit car I bought with a digital dash package, at start up the Oil pressure reads 88, and the oil light blinks?

Submariner409
05-17-09, 11:17 AM
Normal running oil pressures for a Northstar should be HOT: 20 psi at idle, 40 -45 psi cruise (2000 rpm +). Cold, high idle, maybe 60 for a while.

Entirely possible someone stacked one or two washers under the oil pressure relief bypass spring when they built the engine. BUT, that involves quite a bit of disassembly to check. Use a mechanical gauge to check first.

Good oil volume and flow is critical, not so much high pressure. GM likes 40 -45 psi hot, Ford usually likes 45 - 55 psi.

What weight oil are you running ???? 10W-30 should be plenty.

Ranger
05-17-09, 12:48 PM
Sub, are you sure? I recall the Guru once saying that the Northstar oil pressure will only be about 3-5 psi at idle.

geoz3
05-17-09, 02:37 PM
Normal running oil pressures for a Northstar should be HOT: 20 psi at idle, 40 -45 psi cruise (2000 rpm +). Cold, high idle, maybe 60 for a while.

Entirely possible someone stacked one or two washers under the oil pressure relief bypass spring when they built the engine. BUT, that involves quite a bit of disassembly to check. Use a mechanical gauge to check first.

Good oil volume and flow is critical, not so much high pressure. GM likes 40 -45 psi hot, Ford usually likes 45 - 55 psi.

What weight oil are you running ???? 10W-30 should be plenty.



Not sure,

Just bought the car used, I'm going to do a oil change, and will replace with 10W 30, thanks for the info.

Submariner409
05-17-09, 05:09 PM
Just for grins and giggles I went through the painful process of inserting a Stewart-Warner 0-80 psi mechanical gauge (temporary) in a T-system on my 2002 back in 2006. After the oil pressure wars here in 2006 I, too, was questioning what the N* oil pressures really were. My car, hot, 5W-30 Pennzoil synthetic, WIX 51522 filter, runs just under 20 psi at idle and 46 psi at 2000 rpm, highway. My car - maybe not all others, but close........If I had half a brain, the thing would still be there or at least have been the subject of a digital pic or two. I hate idiot lights.

(The FSM does say minimum 5 psi at idle, hot.)

Ranger
05-17-09, 05:24 PM
Wow, that is high per the manual. I was just out in the garage and thought about this and checked it. 5 psi at idle and 35 psi at 2000 RPM. Maybe that is Min., though I did not see that anywhere.

Submariner409
05-17-09, 05:45 PM
Yeah, my 2002 says minimum 5 idle/35 @ 2,000. When you hit minimum you start to worry. The 2002 Helm manual has typos in it, referring your tests to oil pressure minimums on p. 6-11. No such thing. You have to go to Alldata (later edition) to find the spec.

The Olds 455 1972 manual says 30-50 at 2,000, my stock pump boat engines run about 60.

So who's right ???

Ranger
05-17-09, 09:31 PM
Minimum sounds more like it. I just looked for the numbers as opposed to reading closely.

geoz3
05-17-09, 11:49 PM
WOW, I hope the sending unit is bad, or digiital gauge is wrong, I'll also try the Mech gauge and see what that shows. Thanks again for all the info and suggestions. I didn't think 88 was a good number.

Mark C
05-19-09, 07:26 AM
88 on a digital display sounds more like a display or sensor problem than a real reading.