Who makes a good Oil sending unit?

[flyboy1100]

correct on sending unit measurement. One note, cheap voltmeters are horrible on measuring resistance.

i don't have a Fluke, but i have a semi-decent craftsman branded one. will do it tomorrow

 

[foamypirate]

i don't have a Fluke, but i have a semi-decent craftsman branded one. will do it tomorrow

Random question, are you using thread tape on the sending unit when installing it?

 

[yevgenievich]

i don't have a Fluke, but i have a semi-decent craftsman branded one. will do it tomorrow

The cheap ones I am referring to are harbor freight special ones. They are good to identify if there is power present, but not much use after that. Any decent meter should be ok

 

[flyboy1100]

Random question, are you using thread tape on the sending unit when installing it?

i tried with and without. when i did w/o i just used Permatex thread sealant.

what should I be using?

 

[foamypirate]

i tried with and without. when i did w/o i just used Permatex thread sealant.

what should I be using?

Thread sealant should be fine. Sometimes tape can mess up the ground through the sending unit to block/fitting, and throw off the gauge.

 

[flyboy1100]

Thread sealant should be fine. Sometimes tape can mess up the ground through the sending unit to block/fitting, and throw off the gauge.

the bwd s768 had some thin thread tape on it so i left it. guess i will pull it out tomorrow and reinstall with...

1. thread sealant
2. nothing?

 

[yevgenievich]

It would need gobs of tape on it to cause an issue, but just in case worth a try without any

 

[flyboy1100]

Definitely not using gobs. 1 wrap was it.

Sent from my Nexus 6 using Tapatalk

 

[flyboy1100]

Haven't tested it yet, but of it is pegged at zero, it is grounding itself out right? That could just be a wiring problem. My old one didn't work great, but it was leaking too.

Sent from my Nexus 6 using Tapatalk

 

[flyboy1100]

not pegged at zero when i tested it today, but it was stuck at about 18psi. tested the Ohms and it was a steady 22.5. rev'd the engine to about 3000 and it climbed to 25.7. i know i have more oil pressure than that! so clearly the sending unit isn't changing its resistance with pressure

so what is killing my sending units? i haven't checked the wiring diagram but I assume that the sending unit is the last part of the circuit which is creating the resistance before going to ground? i tested the voltage on that wire and it was zero which could confirm my theory here?

 

[flyboy1100]

Both shorted out unit measure 1.8 ohms steady. My new one bounces between all kinds of random numbers and open. Im questioning this though. No pressure should just 0 all the time and not bounce around i would think. EDIT: new one also reads a steady number (must of had bad connection when testing it)

tested voltage on the wire between it and ground and it is a steady 10.35v and 0 Ohms. is this correct? didn't see any cuts or other deficiencies in the wire and traced it all the way to the firewall connector. gauge was still pegged far right when open and at 0 when grounded (and showing 10.35v)

i didn't hook up the new sender because i don't want to fry it just in case that is what is happening. about ready to give up on this and just get a mechanical gauge


Sent from my Nexus 6 using Tapatalk

 

[bucket]

Stuff like this can be frustrating. I'd temp wire another known working gauge to the sending unit and see what it does. I don't think it's possible to fry an oil sending unit

 

[flyboy1100]

Stuff like this can be frustrating. I'd temp wire another known working gauge to the sending unit and see what it does. I don't think it's possible to fry an oil sending unit

there should be voltage at the line though right? i mean it is the ground side, but voltage still is flowing from positive to negative. Should it be the full 12v or even up to the 14.8 my alt is outputting?


i wish i had another gauge, but i think my 60psi gauge got tossed out accidentally

 

[flyboy1100]

there is something funky going on for sure. not sure if the gauge is to blame at this point, or just multiple bad sendors. it will work, then after a while only indicated 10-20 psi. maybe the next time you start it up it will indicate 60+ as it should with cold oil and cold temps, or 10psi. who knows......

where is the best place to mount a mech. gauge? i would love to have it in the cluster, but for removal of the cluster that seems like a pain in the butt!

 

[Georgeb]

For what its worth I had an issue like this and it was the connection between the printed circuit and the gauge on the cluster. The little clips were corroded and it was not conducting correctly. that gauge was all over the place!