OK,
I bought an autometer oil pressure gauge, and had planned to just run it off the port behind the distributor, and not touch the unit by the oil filter. That old fitting isn't coming out. I'm gonna give it 'til tommorow with some penetrant, but I'm now looking at other alternatives. Questions are:

A) Can I run the new gauge off the port by the filter, and simply NOT plug in the oil pressure switch for the fuel pump?

B) Is that stupid? Older cars didn't have this, correct?

C) is there a way to run my new autometer sender and still keep that oil pressure switch?

Thanks,
-Boob

 

The OPSU at the oil filter, if it is the 3 wire job, runs the OEM guage and has the fuel pump circuit as you mentioned. Not sure if this helps any, but as an FYI...

On my car I took the two wires for the fuel pump circuit, and I have them connected together using a relay - that is wiring my fuel pump on when my key is on. The 3rd wire that was for the guage, I have connected to the older style oil pressure guage that I installed there (oil filter), so that my OEM guage still works. (I've done this 'cause I swapped to carb and ditched the ECM, fuel pump relay, etc - I was originally TBI).

I guess what I'm trying to infer is that, the single wire of the 3 that sends signal to the OEM guage works fine with or without the fuel pump wires. Not sure if that helps you.

 

Oh - also....FYI

If you connect the fuel pump wires from the OPSU together, the fuel pump will run, ALWAYS, regardless of the key - that circuit gets a direct connection to the battery.

I'm assuming the new guage has it's own sender that you need to use. The simplest thing I guess would be to remove old OPSU, pull the connector up to the top of the engine bay and tuck the connector away so you'll have access to it later (in case you need an emergency way to make the fuel pump run), and install the new sender for the new guage there. This way, you should still have fuel pump run from ECM (I think - I'd love to know for sure if you try this!).

 

Well, after a lot of cursing, Wd40, and more cursing, I was able to get that plug up on the china wall out, so I'm going that route. I appreciate to info and ideas.

...one thing I was thinking about though, when I had almost given up on the upper connection idea: Why not run a "T" down by the filter? Hook up the new send completely independant, just like I'm gonna do up top, and keep the entire old sender and switch together, working the same as it does now?

Thanks again.

 

Doesn't matter where you access OP.
Ultimately you would have it at the front of engine ( older SBC blocks had the the oil gallery tapped and plugged there ) so as to get earliest indication of oil pressure change as a result of the OP sender being furtherest from the pump