# 1986 Nissain Pickup Oil Light & Gage



## BKJ (May 18, 2011)

Hello, I have just had the motor rebuilt in my pickup. The oil light comes on and the factory gage reads low oil pressure at times. Mechanic has check and said it has good oil pressure and the light and gage (he says it is an electrical gage, not mechanical) work off from a relay that is bad. Does anybody know where this is, the proper name for the relay and if it is available? Thanks for your time.


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## smj999smj (Jan 1, 2006)

Info would help. 1986 was a split year: 1986 models are 720's and 1986-1/2 models are D21 hardbodies. Which do you have? 4WD or 2WD? Which engine? AT or MT?


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## BKJ (May 18, 2011)

*More Infor on 1986 Oil light problem*

Sorry, I forgot to add the following information. It is a 1986 Nissan 720-D, the engine size in 145.6 cu in, automatic transmission, 2WD, Extended Cab. Thanks for your help.


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## zanegrey (Dec 5, 2005)

DID YOU PRIME THE OIL PUMP...?


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## BKJ (May 18, 2011)

I am not sure if he did or not, he is a veteran mechanic, so I would hope so. I have about 2000 miles on the motor, so I feel like there is oil pressure there, the light does not stay on all the time, just at times & he has checked the pressure with the light on. This mechanic is a friend of mine whom I have been doing business with for about 20 years, so I don't think he would lie to me.


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## smj999smj (Jan 1, 2006)

There is no relay in the oil pressure warning circuit. The gauge works strictly off of the oil pressure sender. Typically, the sending unit goes bad or a wire to it "open" or "short circuits" to ground. I can send you the wiring diagram, if you'd like. Send me an e-mail to [email protected] and put "RE: 720-D wiring diagram" in the subject line and I'll send it to you.


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## minitrkingking (May 10, 2009)

I had this problem on my 720s 84, 85, 86' all three were the same issue with your same symptoms. The oil pressure sending unit on the pass side of the motor is most likely bad. Good news is that it's only about $10 and fairly simple to replace. You will need a special socket that is also about $10. Oh yes, it is right under the intake manifold with a wire plugged to it, just pull the wire straight with force.


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## BKJ (May 18, 2011)

Thanks, I was leaning toward replacing that, but was making sure that was it and not a relay. I was not that familiar with the nissan's wiring. Can this be purchased from auto zone, or is this a nissan part, part & socket, thanks.


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## minitrkingking (May 10, 2009)

no problem at all. I bought all 3 of them and the socket at autozone, they will only need to know if you have an oil pressure gauge on the dash. Hope this helps


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## BKJ (May 18, 2011)

Could you please send me the diagram, I tried to email you, but it was returned. My email is [email protected]. I am also having trouble locating the oil pressure switch. Where is it located and what is the best way to get to it. I was wanting the wiring diagram because he may have pinched the wiring going back in with the motor. Thanks in advance for your assistance.


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## BKJ (May 18, 2011)

Could you be a little more specific on the location. I have looked around the oil filter, but I still can't locate it. Can I see it from the top, or do I have to remove a pan or something from the bottom. Thanks


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## minitrkingking (May 10, 2009)

I don't have any diagram, but I'll try to help here. It is a nut about 7/8 of an inch (aprox.) it is unique in that it has dimples in the corners of each side so the special socket won't strip it. On my trucks both with and without motor accessories like a/c, power steering etc... it has been easier to reach from the top passenger side. When they go bad they leak oil like a mofo so it could be covered from sight, and even feel different than it is. Should have a wire that simply pushes on the post (looks like a spark plug) my wires were white or a dull yellow color. I'd say it's about 6 inches above the oil filter and a couple inches toward the front of the motor. I could not really see it and use my hands at the same time so I located it, wiped it good with a rag, then felt around till the socket fit. I forgot to mention that it DOES NOT need to be threaded all the way in, it has excessive threads and only needs to be about 2/3 in the motor, (you'll see what I'm saying). Hope all this helps. I'll try to find a picture for you as well.


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## minitrkingking (May 10, 2009)

http://contentinfo.autozone.com/znetcs/product-info/en/US/wl2/PS100/image/4/
This is right off the autozone site. These are what all mine have looked like but there is potentially a different one for trucks with no gauge.


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## BKJ (May 18, 2011)

I have found my switch, it was just before the oil filter on the passenger side. I went to autozone, and they have 2 different ones listed, one with a gauge and one with a light. My truck has a light and a factory gage in the console. The auto zone one listed for a gauge look right except for the wiring. My truck has two flat connectors and the autozone one has two round pins. Any ideas, or suggestions. The only two options I see is to change my harness to adapt to theirs, or order one from nissan.


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## minitrkingking (May 10, 2009)

I'm at a loss... mine have 1 wire, all round pin. At least you found it! Good luck, remember to post your solution so we can benefit


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