Oil Pressure Gauge Installation

[RRoller123]

I bought a gauge and sender from Csaba years ago, finally getting around to installing it now. Seems we have plenty of time these days....

AR Instructions, for reference:

https://autoricambi.us/fiat-blog/oil-pr ... tructions/

Anyone have any tips or tricks to this? I am particularly interested in how and where you breached the firewall. I have no place on the dash, so I am still undecided where i am going to put this. I am loathe to ruin the glovebox door and sacrifice it for gauges, but with future Altimeter, Barometer, and AFR gauges coming, I may have no choice.

Pete

[18Fiatsandcounting]

Pete, a couple thoughts:

You only need 2 wires to go through the firewall, right? The ones for the oil pressure light and the gauge itself. The other wires on that connector on the gauge are going to be connected somewhere in the wiring behind the dash but they wouldn't go through the firewall. So, those two wires could slip through where the wiring harness already goes through, yes?

What gauges do you currently have in your dash? There are wooden dash panels that have the 2 large holes plus 4 smaller holes, so you could have fuel, temp, oil pressure, and clock. Or do you already have something else in the dash?

Also, do you already have the oil pressure sending units, both for pressure and the light, or is that part of the kit?

-Bryan

[dinghyguy]

If you have the oil pressure idiot light in your cluster you can add on to that for the new gauge idiot light (gives you two) and then you only need one wire to the engine bay. I went through the hole under the brake fluid reservoir . Easy and the wire can be added to the exiting bundle heading down to the starter.

I assume you have the proper oil pressure sender and Y to enable the oil pressure switch to be maintained.

I put the gauge where the clock was, but am looking to put a 6 gauge arrangement in when i redo the dash wood

cheers
Dinghyguy

[geospider]

I just did this.
Yes, ran 1 wire through the spot Dinghyguy used: easy.
also put it in the clock position and used the dash light hot and ground from the clock wiring and used the switched power from the water gauge. All seemed to work fine, EXCEPT; the gauge pegs max when key is turned to the on position. I guess I have great oil pressure... I always thought that meant something was grounding at the sender. ideas?

There is a write up from I believe Focodave, when 81spidermatt was working on it. that is what I went by. Feb, 2014.

Geo

[18Fiatsandcounting]

Geo, I just checked on my spider, and with the ignition in the on position (but not started), if you ground the wire to the pressure sending unit, the gauge pegs. So, my guess is that your gauge is seeing ground when the ignition switch is in the on position, and not the electrical resistance it should be seeing.

Any chance you have the wires reversed between the gauge and the low pressure light? How does your gauge behave when the car is running? Does it start at about mid scale when first started and then drop somewhat as the oil warms up, or ???

-Bryan

[RRoller123]

I have a custom dash, and no more of the flitch of Madrone Burl available that I made it from. Sold a large flitch of it to someone here years ago. This means that I can't really reconfigure the gauge set, so it is going to have to go on either an underneath panel, left or right of the steering column, or under the glove box, probably in a blacked out frame. None of these are wonderful solutions, and the Glovebox position would be the best, but I hate to lose the glove box. It is always something.... (I have to admit that I have the box here with the sensor and Gauge in it and I haven't looked at it in some time).

What a about a gasket or seal at the oil pump where the sensor goes? That would be critical. I wonder if one comes with the complete gasket set, as I have a remnants from this build, maybe there is one in there?

Pete, a couple thoughts:

You only need 2 wires to go through the firewall, right? The ones for the oil pressure light and the gauge itself. The other wires on that connector on the gauge are going to be connected somewhere in the wiring behind the dash but they wouldn't go through the firewall. So, those two wires could slip through where the wiring harness already goes through, yes?

What gauges do you currently have in your dash? There are wooden dash panels that have the 2 large holes plus 4 smaller holes, so you could have fuel, temp, oil pressure, and clock. Or do you already have something else in the dash?

Also, do you already have the oil pressure sending units, both for pressure and the light, or is that part of the kit?

-Bryan

[RRoller123]

Yes, the block/oil pump setup has 2 ports, and I can leave the idiot light in place, and add the pressure sensor on the backside, (opposite) side of the housing, which is actually oriented towards the front of the engine.

If you have the oil pressure idiot light in your cluster you can add on to that for the new gauge idiot light (gives you two) and then you only need one wire to the engine bay. I went through the hole under the brake fluid reservoir . Easy and the wire can be added to the exiting bundle heading down to the starter.

I assume you have the proper oil pressure sender and Y to enable the oil pressure switch to be maintained.

I put the gauge where the clock was, but am looking to put a 6 gauge arrangement in when i redo the dash wood

cheers
Dinghyguy

[geospider]

Actually I left the idiot light where it was. Put the sensor on the front port of the oil filter housing and added the pressure sending unit on the rear side. Did not hook up a wire for the idiot light on the pressure gauge: why have 2.
wondering if the connection at the sending unit has the issue.
Yes, it stays pegged always.

geo

[RRoller123]

Just noticed my idiot light pressure sensor did not come back from the engine rebuilder, so that is something else I have to address now as well..... Tim, we need to check your block.

[RRoller123]

Exactly as I will do it.

Actually I left the idiot light where it was. Put the sensor on the front port of the oil filter housing and added the pressure sending unit on the rear side. Did not hook up a wire for the idiot light on the pressure gauge: why have 2.
wondering if the connection at the sending unit has the issue.
Yes, it stays pegged always.

geo

[geospider]

RRoller,

I will be interested to hear how it turns out, esp if our wiring is the same. trying to figure out why my gauge pegs. thinking something wrong at the sender: must be immed grounding.
geo

[dinghyguy]

On both my cars i added the oil pressure gauge and kept both idiot lights functional, no issues with the gauge reading or the lights. I figure if I decide to remove the gauge and reinstall the clock the original light will still be there for either this idiot or the next one. I did replace all but the ALT idiot light with LEDs so current draw don't matter.
Having said that one oil pressure idiot in the car at a time is fine as well, just depends on preference
cheers
dinghyguy (twice the usual idiot.....)

[18Fiatsandcounting]

trying to figure out why my gauge pegs. thinking something wrong at the sender: must be immed grounding.
geo

Geo, here's what I would do: Disconnect the wire from the oil pressure sensor (not the idiot light sensor). Turn the ignition on. If your gauge pegs, it's not a problem with the sensor. If the gauge needle doesn't move, my guess is that you have a bad sensor.

-Bryan (can easily surpass Dinghyguy at being twice the idiot)

[geospider]

I actually tried this (even with only 1 idiot light)
did not peg: no reading at all, of course.
Will call AR on monday
wondering if there is a way to fix; guessing it is somehow "grounding itself"

thanks,

Geo

[18Fiatsandcounting]

Sounds like a bad pressure sensor, Geo.

-Bryan