oil pressure gauge

[roy c]

Hello again oil pressure gauge is not working, is the sending unit by oil filter?
swap out see what happens

 

[crazy4offroad]

Correct, by the filter.

 

[smurph20]

Maybe on the fi motors but mine is on the back of the block just below the dizzy buts its carbed too.

 

[crazy4offroad]

That's where the pressure switch for the dummy light goes, the sending unit for the gauge wont fit there, it goes by the filter.

 

[smurph20]

Thats where mine is hooked up and its for the guage thats why im saying maybe for a fuel injected motor but my carbed motor is behind the dizzy

 

[crazy4offroad]

Mine is carbed and it is by the filter. Weird.

 

[smurph20]

Im guessig as long as its getting a pressurized oil signature it doesnt matter

 

[bucket]

The factory used both locations, and either will work if there's clearance. From what I've seen, they were usually mounted up behind the dizzy (trucks and cars). IIRC, my '84 has one down near the filter too, it had something to do with the original choke I think. Then when FI came in, I think there were two sending units again, but this time, the big honkin new style gauge sender is down near the oil filter. I think the smaller old style unit up behind the dizzy ties into the fuel pump circuit, in case the fuel pump relay fails.

 

[smurph20]

My 92 S10 is reversed of what you said. The one down by the oil filter is the one for the fuel pump kill

 

[bucket]

My 92 S10 is reversed of what you said. The one down by the oil filter is the one for the fuel pump kill

Interesting, I never paid much attention to how my '91 is set up.

But since you mentioned it, that pressure switch is actually there to supply power, not kill it. It's a back-up in case the pump relay fails. So if you ever have an extended crank, it could just be due to a failed pump relay. It's common belief that it kills power, but it actually isn't set up that way.

 

[smurph20]

When the one by the oil filter failed it wouldnt start without it so wether it kills power of supplies power without it wont run lol If i loose oil pressure on the guage its shuts off immidiatly which is nce cause that saves the motor if in fact there is no oil

 

[bucket]

When the one by the oil filter failed it wouldnt start without it so wether it kills power of supplies power without it wont run lol If i loose oil pressure on the guage its shuts off immidiatly which is nce cause that saves the motor if in fact there is no oil

That's really odd. I've pulled up diagrams on a few of them and confirmed, and people have driven their trucks in the shop with ZERO oil pressure. One was a '91 C2500, and it didn't even have an oil filter on it.