jbherri2

iTrader: (1)

Is there a good way to verify the oil pressure? When I'm at idle, the oil pressure seems to drop very low, at least according to the gauge on the dash. Is there a way to verify to actual oil pressure?

thanks!

DivinDriver

iTrader: (15)

Use a calibrated test gauge.

Rogue_Wulff

The best way is using a mechanical oil pressure guage, but it's not real easy to hook up since the stock oil pressure sender can have oddball threads.
I keep a banjo bolt for the oil cooler return line handy, that has been drilled/tapped to accept the proper fitting for an oil pressure guage. Only takes a couple minutes to swap the bolt and hook up a mechanical OP guage.
Of course, I left that setup in place on my car, and have a mechanical OP guage under the dash, since the factory OP guages are so accurate............

DreamInRotary

iTrader: (49)

Running at 250*F + water temp, oil temp under 140*F, running 10w40 conventional oil. Didn't cost much and only takes about 45 minutes to install completely correctly.

jbherri2

iTrader: (1)

Thanks for the photos, that helps. My car is bone-stock, and I'd like to keep it that way for the foreseeable future. It looks like you've got something between the oil filter and the beehive cooler. Is that the case, or did you drill & tap? My preference would be something that I can hookup, verify my oil pressure, and then take off again without any substantial modifications. However, is that possible? I'm really learning as I go here.

thanks again!
Jonathan

DreamInRotary

iTrader: (49)

Yeah Jon,
That's called an "oil filter sandwich adapter" with 1/8 NPT threads for the sensors on gauges (both electric and mechanical) and can be taken on and off at leisure. I ordered it on eBay for around $20 and it comes with two different adapters for the two different thread sizes of oil filters (don't worry, one of them works) and has two o-ring style gaskets that seal it where the oil filter would normally seal. So it's just like raising the oil filter by about 1/2 to 3/4 of an inch. Just have a gauge that you could hook up and you'd get a reading in no time!

*Just so you know, the gauge I had hooked up to that adapter read about 20psi higher than the stock cluster gauge did when cold. After it warmed up it was the same. Not sure why that was to this day but it didn't bother me any.

85TIIDEVIL

iTrader: (2)

According to the stock gauge, the pressure at the "oil filter sandwich" is read considerbly lower then the stock location. I have both and my wire is long enough to reach either one.

85TIIDEVIL

iTrader: (2)

Actually... My last post I'm wrong. I have one tapped into the banjo bolt at the oil cooler return on the bottom of the rear plate, the other at the "oil cooler sandwich". I even swapped the same sensor to and from both spots to make sure it wasn't the difference in the reading. Anyways, different spots give different readings.

jbherri2

iTrader: (1)

Uhm....so what's the best advice? =)

ray green

iTrader: (14)

Jonathan, could you post a video or a couple still shots showing your stock oil pressure gauge at idle and then again with it revved up to around 3000-4000 rpm?

Chances are your stock gauge is working fine. It's normal for the pressure to drop down at idle but it should increase to around 60 lbs/in2 when revved.

DreamInRotary

iTrader: (49)

Yes, this

jbherri2

iTrader: (1)

I added 2-stroke today to the gas tank, in the event that I've got something going on w/ my OMP. Maybe these two threads should be combined? Maybe I'm chasing ghosts? I dunno.

Per request, here are pictures of my oil gauge at 1000, 2000, and 3000 RPM... The car was warm, as I'd been about four miles or so (round trip) to the gas station. The light is b/c I had the parking brake set.

1000RPM


2000RPM

3000RPM

DreamInRotary

iTrader: (49)

Pretty sure mine at idle is at about your 2,000RPM mark and when revved to 3,000RPM it is a little above 60psi.. maybe a connection needs to be cleaned?

ray green

iTrader: (14)

Looks good to me Jonathan, I wouldn't worry about it. Volt meter is also right on.

And that odometer is especially impressive!

jbherri2

iTrader: (1)

It's a happy odometer. =)
For whatever reason, I was thinking my oil pressure was higher than I'm currently showing. Should I try to verify it w/ some other means as discussed earlier? Seems there is not a firm agreement as to the reliability of the factory gauge.

ray green

iTrader: (14)

Well, I think the main charge against the 20+ year old stock gauges, vs installing expensive aftermarket gauges, is that the stock gauge is not as accurate.

But so what? Does it really matter if the oil pressure at 3000 rpms is 60, 58 or 64 psi?

What you want is reliability and you will get this if your gauge is behaving consistently. If the stock gauge starts to do things differently, that's when you should get concerned.

Most often, it's just a problem with the gauge itself, usually with the connection, which is an easy fix. If the stock gauge really does stop working because of the gauge itself, that's when you should look into installing an aftermarket unit.

But sometimes squirrelly behavior in the oil pressure gauge is something more serious that actually reflects problems with oil pressure, and the stock gauge will detect these problems just as well as an aftermarket gauge.

But of course, having a backup aftermarket gauge won't hurt anything, so if you want a few more dials crowding the dashboard, sure, why not?

More important than the oil pressure gauge is a backup temp gauge, in my opinion. Small differences in temp behavior can be an early sign of all kinds of problems that can be caught early and repaired before you end up with a breakdown on the road or worse.