Oil Pressure Gauge Installation

[RRoller123]

So, on my system, the sender (which is brand new, only the gauge was bought as used) has only a single wire (Faston tab). This actually makes things a lot easier, routing just the one wire, and I will use the idiot light that is already in the tachometer face as is, don't need two.

Curious about the seal at the oil pump, I am assuming that this small ring, which appears to be steel, clear chromated, is all that is required? Need to make some inquiries before I install the sender to be sure. Looks like maybe it is intended to crush on the conical part of the housing? This has to be paid attention to and done right, loosing all your oil through a bad sender fitting would not be a good thing.

[RRoller123]

Does the sender for the low oil pressure idiot light in the tachometer require any teflon tape or (God forbid) RTV, or does its seal rely exclusively upon the crush washer? Torque spec is 26 ft-lbs.

Thanks, Pete

[18Fiatsandcounting]

I've mostly relied on just the crush washer, and occasionally a single layer of Teflon tape, for both the gauge sensor and idiot light sensor. Either has seemed to work fine, and most of the leaks that I see from the gauge and idiot light sensors are from the body of the sensor itself, not from the fitting into the engine. On one of my sensors, oil actually dripped out of the rivet that attached the electrical contact to the end of the sensor.

-Bryan

[RRoller123]

Thanks!

[dinghyguy]

i actually agree with Bryan, the crush washer has been fine for me. I cant remember if i put a thin smear of gasket goo on the washer but i don't think so.

if you are not keeping the clock you may be able to use the plug and just move some of the wiring around to suit the sender, thus making use of the ground (white black) , and the light power wire (white red). The power wire on the clock is red black, but is powered all the time, so i didn't use that. I did see that the gauge wiring diagram has a device of some sort internal to the gauge connecting terminal 31 and + on my diagrams. Thus i connected a yellow/black wire to the + (or you could move the one from the tachometer) and also the grey/yellow (or also move it from the tach) and then your new wire from the sender. If you do that the gauge and idiot light will work. I am not sure if the gauge will work if you just connect the dash light and the sender wire (i doubt it)

Oh, both mine are '79 so not sure if the wire colors are correct for other cars.

cheers
Dinghyguy (with dual olio pressure idiot lights)

[RRoller123]

Thanks. That is helpful. I am keeping the clock, so still sort of stuck on where to put this thing. But that is just an aesthetic issue I have to answer. I sometimes see gauge sets mounted at the bottom of the dash, left or right of the steering column, or under the glove box above the passenger's legs. Seems like there is enough room there, if the wires are well protected. None of it is wonderful. I could pull the center console and do surgery to the steel support bars behind there and move the idiot lights down, put the gauges in above, but dammit, this has taken long enough, I am loathe to extend this project any further.

I wonder about fitting a new crush washer (have to cut the old one off the idiot light sender, won't spin off) or maybe reusing just that one with some teflon tape. The new Pressure Sender obviously has a new one. Never mind, just thinking out loud here, will measure the new one and see if I can find the exact same size somewhere. My kingdom for a nail, isn't it always the tiniest little things that slow us up? But rush too quickly ahead and meet our friend named disaster. My block fitting got painted, so I have to figure out how to get the paint out of there so there is a ground connection for the pressure sender, and then it should all work.

I agree that gauge will need power and ground as well as the light and sender wires. Can pull the light and ground from somewhere else, no problem, just depends where this thing ends up.

[Coolbreeze]

I could not find a Veglia oil pressure gauge; so, I used a Sunpro mechanical gauge. The replacement radio has a clock on its face, which meant the dash clock could give up its position to the new gauge. I like the greater needle swing on the Sunpro compared to the Veglia. The mechanical gauge is a bit harder to install than an electrical one, but it should be more accurate and reliable.

I would include a photo of my gauge in the dash, but I do not know how to post a photo with a message.

[RRoller123]

Thanks for following up, I have put this on the back burner for now, as I work on the idle issues, and break in the new engine. I do have the pressure sender installed, with no leaks, so that is half the battle right there. There are two ports on the oil pump available; cars with no oil pressure gauge have the idiot light port sensor in the rear port, and a cap occupying the front port, directly opposite the rear port on the pump. I moved the idiot light sensor to the front since it is smaller and less likely to interfere with the belts, etc, and put the pressure sensor in the rear position, where it is a little better protected. Eventually I will decide where to mount the gauge, and wire it up.

Pete