Oil Sending Unit

Vetteonr

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Mar 10, 2022
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6
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Prescott, Arizona
I just discovered that the yahoo who owned my jeep before me must have removed the oil sending unit. They installed a plug where the unit would go and left the wire hanging there. Does anyone have any ideas on how to remedy this? I'll attach a photo. Thanks!
IMG_1162.jpeg
 

Flyer58

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Apr 12, 2020
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Magnolia, Texas
Short answer is remove the plug and install a new pressure sending unit and plug in the connector. It should be a standard 1/4in pipe thread.

Long answer is those sending units have a history of splitting open and sending all you oil out over the road and if you don't catch the pressure needle fluctuating then the sound of an engine running without oil will.

This happened to the previous owner of my 92 YJ and it trashed the engine. As a test I put a temporary plug in along with a few quarts of oil but the engine was too far gone. The sending unit was spraying out about a quart every minute.

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SirDoopYJ

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Stick Red, Louisiana
Short answer is remove the plug and install a new pressure sending unit and plug in the connector. It should be a standard 1/4in pipe thread.

Long answer is those sending units have a history of splitting open and sending all you oil out over the road and if you don't catch the pressure needle fluctuating then the sound of an engine running without oil will.

This happened to the previous owner of my 92 YJ and it trashed the engine. As a test I put a temporary plug in along with a few quarts of oil but the engine was too far gone. The sending unit was spraying out about a quart every minute.

View attachment 119628

View attachment 119629

View attachment 119630
Were you able to salvage the original head? or was that toast too?
 

Flyer58

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Apr 12, 2020
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Magnolia, Texas
I can install the new sender but my question is about the wiring. As you can see in the photo the plug in part is not there.
Ok I see that now. You'll have to search online for an oil pressure switch connector for your year/model YJ along with a pressure sending unit. I got my sending unit at AutoZone.
 

Gilaguy23

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Apr 12, 2021
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611
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Q town New Mexico
The connector is nothing but a female spade connector on my 91. Of course the OEM one has a plastic boot over it but its fine without it. Personally Id install an aftermarket oil gauge and sender as the oem gauges are as about accurate as Biden and his mouth piece Pistaki.
 
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machoheadgames

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May 19, 2020
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Dallas, TX
On 92-95 the oil pressure switch has a 1 wire connector. Buy the connector, the sending unit, splice on the connector and plug em up.

Personally my gauges have never been anything but fully accurate. The older 87-91 gauges are in general, a lot less reliable. There are still problems with some of the later ones too but I have seen many that work perfectly fine.
 

machoheadgames

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Thanks macho. I was looking at those on rockauto and was concerned that it is a one wire set up and the connector has two wires.
Oil pressure circuit is a simple one wire setup. There is only one terminal inside the sending unit itself. For whatever reason, Jeep decided to use a two terminal connector for it. You'll be good with those parts for sure.
 

Sunsport

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Dec 5, 2020
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Halifax, Nova Scotia
As others have said, looks like a quick fix for you - install a new unit and replace the connector. I have never had one leak on mine, but my original did go bad and was reading pretty much pegged all the time. I replaced it with one from rock auto and it has been good ever since. About 10 minutes to change (or less) on my 4.2.
 

machoheadgames

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Did you just twist those wires together and put elec tape on them or are they soldered? Just curious.
Not sure what he did but in my mind a mechanically crimped butt connection with weather sealed heat shrink is pretty much always best. I don’t like soldering as I find it to be more work to install and not any better performance or durability than crimping. In other words, I see no reason to solder.

I don’t consider twisting/taping wires with electrical tape to be a viable install ever really. After a while electrical tape gets gooey and starts coming apart and eventually that connection will fail.
 
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Flyer58

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I usually brush on some liquid electrical tape over the crimped connectors and never had any problem other than it dripping on clothing but one it sets it lasts forever.
 

Stoopid Jeep

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Dec 25, 2021
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North Idaho
Since we're sharing. I solder every splice and wrap it in adhesive lined heat shrink. When done properly, the splice is less than an inch long and is barely noticeable. It fits in a wire loom and is a lifetime fepair. I'm super OCD about wiring. Butt connectors make my eye twitch.
 

machoheadgames

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Since we're sharing. I solder every splice and wrap it in adhesive lined heat shrink. When done properly, the splice is less than an inch long and is barely noticeable. It fits in a wire loom and is a lifetime fepair. I'm super OCD about wiring. Butt connectors make my eye twitch.
I think if you saw what I use you would agree they are a lifetime repair.
 
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