AMC Eagle Den Forum

The Mighty 258 => The Engine => Topic started by: vangremlin on May 26, 2011, 05:25:42 PM

Title: Oil pressure too high?
Post by: vangremlin on May 26, 2011, 05:25:42 PM
So my oil pressure has always been about 40-50 psi at start-up, dropping down to 15-20 at idle when warm, and usually being right around 40 as I'm driving down the road.  This is all on the factory gauge in my floor console.  Today, as I'm driving on the highway doing 70 mph (just after meeting Shanebo and selling him a console with no gauges) I noticed the oil pressure was now reading about 70 psi, dropping down to about 50 psi at idle.  I know that there are always questions about these electrical gauges, and I have a mechanical one at home I can throw on this weekend to be able to compare.  Is there anything else that could be going on that would cause this big jump?  Engine sounds fine.  I also noticed that the needle would fluctuate just like the voltmeter when the turn signals were on.  Thanks in advance!
Title: Re: Oil pressure too high?
Post by: n9xvt on May 26, 2011, 05:32:29 PM
just for sake to say so i would check the voltage at the battery when running,,and or in the cabin,,my reasoning being that if one were to look at a schematic voltage goes thru the sensor to the gague and i reason tht if voltage is high readings would be high as well,,my second guess would be sending unit fail,,
Title: Re: Oil pressure too high?
Post by: shanebo on May 28, 2011, 01:14:33 AM
I sure hope my bad luck with cars didnt rub off on Pepe!! My guess is the sending unit or somthing electrical. I cant think of anything off the top of my head that would suddenly create an increase in oil preassure.
Title: Re: Oil pressure too high?
Post by: 68AMXGOPAC on May 28, 2011, 07:44:19 AM
I'm not sure on the sixes, but my V8 pump has a relief spring inside so it doesn't over pressurise , I would go with the elctrical thoughts.
Title: Re: Oil pressure too high?
Post by: vangremlin on May 28, 2011, 09:19:41 AM
I changed the oil filter last night because that seemed like a really easy thing to do and rule out the filter being plugged and the bypass opening.  No change.  Today I'll hook up a mechanical gauge to see what it reads.

And Shane, I'm sure there is no bad luck from you being the cause.  In fact, me passing the console on to you was a way of sending good luck your way.  That's the way I look at it anyway  ;)
Title: Re: Oil pressure too high?
Post by: thereverendbill on May 28, 2011, 11:12:29 PM
if the gauge fluctuates with a signal on my guess is ither the gauge is shot or a ground is messing up ...... a mechanical gauge is the only true way to be sure
Title: Re: Oil pressure too high?
Post by: vangremlin on May 28, 2011, 11:26:27 PM
Quote from: thereverendbill on May 28, 2011, 11:12:29 PM
a mechanical gauge is the only true way to be sure

So I plumbed in a mechanical gauge today...and the readings are what you expect.  At idle when warm its about 20 psi, at cruising speed its around 50-55 depending on RPMs (maybe even up to 60), and around 50-60 when first starting up and cold.  The oil pressure is even a little higher than I thought it was so that's good.  The factory gauge didn't move with along with the mechanical, and never got below 40.  So I'm pretty confident my engine is safe, but now need to figure out whether to try to trace down the problem with the factory gauge, or replace all of the gauges with new ones.  Casper said he mounted 2" gauges in the factory console without a lot of work so that may be the way to go.
Title: Re: Oil pressure too high?
Post by: shanebo on May 28, 2011, 11:53:19 PM
I think Tougeagle replaced his stock gauges with aftermarket....They look real nice....bright and easy to see too.
Title: Re: Oil pressure too high?
Post by: vangremlin on May 28, 2011, 11:55:22 PM
Quote from: shanebo on May 28, 2011, 11:53:19 PM
I think Tougeagle replaced his stock gauges with aftermarket....They look real nice....bright and easy to see too.

Didn't he mount them up in the little cubby hole above the radio on his non-A/C car?  If I fill my cubby with gauges, I'm going to need one of those floor consoles with a cubby hole - wonder where I could find one of those lol
Title: Re: Oil pressure too high?
Post by: thereverendbill on May 29, 2011, 12:56:03 AM
that is what I am going to do with the gauge console I have for the kammy ..... just replace those stock gauges with a set of autometer gauges plus I think 2 clocks in the car would look pretty tacky
Title: Re: Oil pressure too high?
Post by: Eagleearl on May 29, 2011, 05:17:42 AM
If the gauge is moving when the turn signal blinks it is probably the ground is weak and needs to be cleaned up. A mechanical gauge would probably be more accurate though.
Title: Re: Oil pressure too high?
Post by: vangremlin on May 29, 2011, 09:00:23 AM
Quote from: casper on May 29, 2011, 01:10:38 AM
i put in all new mechanical gauges in my console. theres a molded in ridge around each gauge face. i took the dremel, and trimed those ridges out and the new autometer gauges fit great. 

Casper, you're talking about the molded in ridge on the front of the console, right?  Thanks.
Title: Re: Oil pressure too high?
Post by: eaglefreek on May 29, 2011, 02:45:33 PM
Quote from: casper on May 29, 2011, 01:10:38 AM
i put in all new mechanical gauges in my console. theres a molded in ridge around each gauge face. i took the dremel, and trimed those ridges out  
That's exactly what I did with mine except I went with electrical gauges. I don't like the idea of pressurized oil in the passenger compartment.
(http://img.photobucket.com/albums/v637/svoman2300/utf-8BSU1HMDAzMjAtMjAxMTA1MjktMTMyOC5qcGc.jpg)

Title: Re: Oil pressure too high?
Post by: vangremlin on May 29, 2011, 03:25:48 PM
Quote from: eaglefreek on May 29, 2011, 02:45:33 PM

That's exactly what I did with mine except I went with electrical gauges. I don't like the idea of pressurized oil in the passenger compartment.

Which four gauges did you put in - looks like oil pressure, oil temp, engine temp, and volts?

I have a factory oil pressure gauge in my 97 Ford Expedition and it makes me laugh - the pressure never changes.  Drops to the bottom of the scale when you turn it off, but otherwise its at about 70% of the scale, no matter what temp the engine is at, amount of oil, weight of the oil, etc.  Looks the same today as when I bought it new, 197,000 miles ago!
Title: Re: Oil pressure too high?
Post by: eaglefreek on May 29, 2011, 03:31:42 PM
Quote from: vangremlin on May 29, 2011, 03:25:48 PM
Quote from: eaglefreek on May 29, 2011, 02:45:33 PM

That's exactly what I did with mine except I went with electrical gauges. I don't like the idea of pressurized oil in the passenger compartment.

Which four gauges did you put in - looks like oil pressure, oil temp, engine temp, and volts?

I have a factory oil pressure gauge in my 97 Ford Expedition and it makes me laugh - the pressure never changes.  Drops to the bottom of the scale when you turn it off, but otherwise its at about 70% of the scale, no matter what temp the engine is at, amount of oil, weight of the oil, etc.  Looks the same today as when I bought it new, 197,000 miles ago!
The other temp gauge is transmission temp. After having it in there about 6 months, I'm confident my transmission cooler does it's job quite well and may be replacing it with my new AEM wideband O2 gauge if I don't find a convenient location for it..
(http://img.photobucket.com/albums/v637/svoman2300/aemwidebanduegoblk.jpg)
Title: Re: Oil pressure too high?
Post by: tougeagle on May 29, 2011, 10:42:07 PM
I made
Quote from: vangremlin on May 28, 2011, 11:55:22 PM
Quote from: shanebo on May 28, 2011, 11:53:19 PM
I think Tougeagle replaced his stock gauges with aftermarket....They look real nice....bright and easy to see too.

Didn't he mount them up in the little cubby hole above the radio on his non-A/C car?  If I fill my cubby with gauges, I'm going to need one of those floor consoles with a cubby hole - wonder where I could find one of those lol
Quote from: vangremlin on May 28, 2011, 11:55:22 PM
Quote from: shanebo on May 28, 2011, 11:53:19 PM
I think Tougeagle replaced his stock gauges with aftermarket....They look real nice....bright and easy to see too.

Didn't he mount them up in the little cubby hole above the radio on his non-A/C car?  If I fill my cubby with gauges, I'm going to need one of those floor consoles with a cubby hole - wonder where I could find one of those lol

The facia plate that fits over the gauges is removable, my center console never had a cubby, I made it into one by simply removing the gauges and plate, and using that plate as a mounting medium for my gauges.

(http://i72.photobucket.com/albums/i161/Wolf_n/Eagle/Mods/Interior/100_0100.jpg)

The oil temp gauge sending unit fits right in place of the 5/16" female pipe plug just above the oil filter and the oil pressure gauge unit fits where the old temp switch was located. I used copper line.

As a note, my oil is around 17 psi at idle and around 45-55 when driving, warm. Keep in mind that high oil pressure isn't necessarily a good thing. Higher pressure means less flow. When the engine is cold my oil pressure at idle is 70 psi, with 5w30 synthetic oil, because oil is thicker when cold and therefore flows slower..
Title: Re: Oil pressure too high?
Post by: vangremlin on May 29, 2011, 10:59:53 PM
Quote from: tougeagle on May 29, 2011, 10:42:07 PM

Didn't he mount them up in the little cubby hole above the radio on his non-A/C car?  If I fill my cubby with gauges, I'm going to need one of those floor consoles with a cubby hole - wonder where I could find one of those lol

The facia plate that fits over the gauges is removable, my center console never had a cubby, I made it into one by simply removing the gauges and plate, and using that plate as a mounting medium for my gauges.

The oil temp gauge sending unit fits right in place of the 5/16" female pipe plug just above the oil filter and the oil pressure gauge unit fits where the old temp switch was located. I used copper line.

As a note, my oil is around 17 psi at idle and around 45-55 when driving, warm. Keep in mind that high oil pressure isn't necessarily a good thing. Higher pressure means less flow. When the engine is cold my oil pressure at idle is 70 psi, with 5w30 synthetic oil, because oil is thicker when cold and therefore flows slower..
[/quote]

Your point about the higher oil pressure not necessarily being a good thing is why I was concerned when mine spiked up - I was concerned that something got plugged and oil wasn't getting around inside the engine.  The mechanical gauge helped rule that out.

My statement about the cubby in the console was just giving Shane a hard time - I just sold him a console with cubby lol.

And I notice you have the hole in your dash where the passenger mirror adjuster used to be.  I replaced my mirror and was stuck with the same hole.  If you go to the hardware section in Lowe's (where the screws are) you'll find a black one inch plastic plug that fits perfectly in there.  Its in the drawers with automotive type parts, also near the desk plugs.  Looks great to fill in the hole.  I'm sure other hardware stores like Ace would also have them. Cost about $1 for 2 of them.
Title: Re: Oil pressure too high?
Post by: shanebo on May 30, 2011, 02:01:06 AM
Ya know a set of digital gauges would be real sharp...Dakota digital makes a whole bunch of different and really cool guages...Somewhere, I dont remember where, if it was here or somewhere else on the net a guy did put a full digital set instrument cluster.
Title: Re: Oil pressure too high?
Post by: tougeagle on May 30, 2011, 09:31:45 PM
Quote from: vangremlin on May 29, 2011, 10:59:53 PM
Quote from: tougeagle on May 29, 2011, 10:42:07 PM

Didn't he mount them up in the little cubby hole above the radio on his non-A/C car?  If I fill my cubby with gauges, I'm going to need one of those floor consoles with a cubby hole - wonder where I could find one of those lol

The facia plate that fits over the gauges is removable, my center console never had a cubby, I made it into one by simply removing the gauges and plate, and using that plate as a mounting medium for my gauges.

The oil temp gauge sending unit fits right in place of the 5/16" female pipe plug just above the oil filter and the oil pressure gauge unit fits where the old temp switch was located. I used copper line.

As a note, my oil is around 17 psi at idle and around 45-55 when driving, warm. Keep in mind that high oil pressure isn't necessarily a good thing. Higher pressure means less flow. When the engine is cold my oil pressure at idle is 70 psi, with 5w30 synthetic oil, because oil is thicker when cold and therefore flows slower..

Your point about the higher oil pressure not necessarily being a good thing is why I was concerned when mine spiked up - I was concerned that something got plugged and oil wasn't getting around inside the engine.  The mechanical gauge helped rule that out.

My statement about the cubby in the console was just giving Shane a hard time - I just sold him a console with cubby lol.

And I notice you have the hole in your dash where the passenger mirror adjuster used to be.  I replaced my mirror and was stuck with the same hole.  If you go to the hardware section in Lowe's (where the screws are) you'll find a black one inch plastic plug that fits perfectly in there.  Its in the drawers with automotive type parts, also near the desk plugs.  Looks great to fill in the hole.  I'm sure other hardware stores like Ace would also have them. Cost about $1 for 2 of them.
[/quote]

I'm going to use an interlock cable from rocky mountain supply to put in that hole, to shift the transfer case from awd to 4 low as needed. One of these days though....
Title: Re: Oil pressure too high?
Post by: shanebo on May 30, 2011, 11:44:14 PM
My cubby has a guage in it!!!...it shows me how much change I have.... ;D
Title: Re: Oil pressure too high?
Post by: tougeagle on May 31, 2011, 01:10:35 AM
Quote from: shanebo on May 30, 2011, 11:44:14 PM
My cubby has a guage in it!!!...it shows me how much change I have.... ;D
lol, nice