mega oil pressure, is this a problem?

[GTwannaB]

just rebuild my motor and it has 1100 miles on it as of today so i figure its broken in pretty good.
my question is about my oil pressure , i dont know if too much is a bad thing or not? my oil pressure gauage is pegged and theres no numbers just high and low so i dont know how many pounds of pressure that is
anybody know?
and why is it that i put in thinner oil for winter and the oil pressure actually increased

 

[HISSIN50]

Year and make will help. Too high of an oil pressure can cause issues with the oil film between parts, as well as issues with filters, etc.

I would put another guage on there to you know if it is a gauge issue or not. With a new motor, I would run a real gauge anyhow, but that is just me.

Good luck.

 

[GTwannaB]

its an 89 motor in a 95 car,

 

[65ShelbyClone]

You should at least get an aftermarket oil pressure gage; the stock gages tell very little. More than 80psi cold/60psi hot is too much for a street engine. The rule of thumb is 10 psi for every 1000rpm.

Also make sure your factory oil gage doesnt have a short anywhere. It would take something like 100psi+ to peg the stock gage.

 

[bobbys9350]

Sounds like a gauge problem to me for sure......

Throw a good Autometer Mechanical gauge on there....
Good Luck

 

[sgarlic]

Is it pegged all the time, at hot idle, at cold startup, etc?

If so I'd definately suspect the gauge, or the sending unit.

FYI: Not that this necessarily applies to your situation, but my 4.6 has over 75psi at cold startup, and pegs the autometer gauge if I really get on it for the first few minutes when cold.

 

[GTwannaB]

good guess, i crawled under the car and changed oil it turns out that both the wires for the oil sending unit are cut
so that means its just a bogus guage reading right?

 

[HISSIN50]

good guess, i crawled under the car and changed oil it turns out that both the wires for the oil sending unit are cut
so that means its just a bogus guage reading right?

The OP sender only has one wire. It is a bell-shaped sender located above the oil filter.

Seems to me that the low oil level sensor (located on the side of the driver side of the sump) has two wires though.

Good luck.

 

[GTwannaB]

hhhhmmm i guess i had better take another look? can i see that sensor from looking down thru standing?

 

[HISSIN50]

hhhhmmm i guess i had better take another look? can i see that sensor from looking down thru standing?

yep. When standing, looking over the driver side fender, look down toward the oil filter. Then look above it and to the front of the car a little. You should see the sender, with its one wire attaching to the top of the bell.

Ohming out that wire with the car off can be revealing.

Good luck.

 

[GTwannaB]

thanks alot for the assist , ill post whatever i figure out if anything

 

[5.0Droptop]

My 347 will peg the 100 psi autometer gage when cold. It runs 60-70 psi when hot and crusing. Runs 35-45 at idle.
I cant use flimsy filters or it will seporate the crimp seal and leak. I have to run a more rugged stiff filter for no problems. I have a cheap motorcraft filter in the garage that it blew open to remind me not to buy thin flimsy filters. It was on there for awhile before it busted it but I dont want that happeneing again. lol

 

[GTwannaB]

it turns out that i have a different stile sending unit on there? I didnt know that that would make a difference but an expert looked before i said anything and told me that it looked different and that when there the wrong one the guage will peg

 

[HISSIN50]

it turns out that i have a different stile sending unit on there? I didnt know that that would make a difference but an expert looked before i said anything and told me that it looked different and that when there the wrong one the guage will peg

I still would do away with all that and just buy a real gauge and install it.

However, dealing with the stock guage and sender, I would go buy a new sender that is correct for your year of car at the parts store, dealer, etc (they are about 10 -15 bucks at parts stores).

What does this sender you have look like?

Good luck.

 

[The Shape]

Since he has an '89 motor in a '95 wouldn't he need to purchase the OP switch for a '95 for his stock gauge to work right? I was under the impression that the 94-95 cars oil pressure gauges basically just worked off of a switch where the needle just sets dead center of the gauge unless you drop below a certain psi (I think 7) . The sender on an '88 engine is an actual electric sending unit that alows the gauge to move with rpm changes and such correct???

 

[HISSIN50]

James, you hit on something I missed.

The SN95 oil sender is a tiny little guy, like a oil idiot light on many cars. You cant really see it from on top (if he has SN95 accessories). ANd it does not use the hex tube that foxes have.

So since it looks like James hit the nail on the head, if the sender is pretty small (a little beige cannister) then that sounds like an SN95 OP sender.

James, I have read that same info about the SN gauge calibration. It seems to move about the same as the fox ones, for whatever that is worth (I dont think either are reliable). Good catch.

 

[GTwannaB]

yeah its a little beige one

 

[GTwannaB]

are you guys saying that the sender does nothing at all until the car drops down to like 7 psi pressure? cuz im no mustang genious and i dont know the little stuff that isnt common knowledge

 

[HISSIN50]

are you guys saying that the sender does nothing at all until the car drops down to like 7 psi pressure? cuz im no mustang genious and i dont know the little stuff that isnt common knowledge

I first heard that from Andy (Rio 5.0), who knows his stuff. I have not referenced it from any official source though.

As for your gauge, the sender is either bad or I have a feeling that the wire is chafed and pegging the gauge.

But with James' info, you can see that a real gauge is a nice addition anyhow.

Good luck.