I wonder if this is why some engines have a no start situation?

I too would also like that parts list. To bad Ford is doing this in such a fashion. I think you would have internal damage if the computer waited until 7 PSI to shut us down, especially if it were to run at that pressure for a while.
Seems to me that the set up on the international engine would also be tied to the computer. That is unless it has a totally different computer on the international version. Anyone want to venture a guess, if the computer just sees ground, or a certain voltage due to the switch internal resistance? If it is a voltage(due to variable resistance), then maybe the old unit would not need to be teed in, Just simply connect to the new analog unit.

Bob A. Does the ranger you speak of shut down without the wire grounded? If so, definately could not harm the puter to connect it with the variable resistor in the sending unit. Just would see less ground. See that all the time when the key is on but no t running. Worst that would happen, it would not start.

Parameters are available to the computer. Is this one of them? Perhaps this is more than a switch, but if there is a resistor on the dash, then it may just allow the guage to SEE one pressure?? Anything above 7 psi shows mid guage?? I remember this being done with a 89 ambulance with the IDI 7.3 that we had by FORD, so no one would worry about the oil pressure. I had a 93 IDI 7.3, and the pressure went really low. Pulled the sending unit, started the engine momentarilly, with a rag over the opening. Cleaned the sending unit and reinstalled. Oil pressure was fine. Something in the port obstructing the inlet on the pressure sending unit, I guess. Simple things. Ford can't figure out.

Lariat

 

There isn't a shut down problem with the connection to the analog sending unit

 

New Information

On page 56 of the PSD Manual it lists the EOP (engine oil pressure switch)
The followinf is a quote:
- The EOP is a switch that closes a circiut to ground after engine oil pressure reaches approximately 5 - 7 psi.
- This switch controls the oil pressure gage on the instrument panel. When pressure is above 7 psi the gage will read normal and if the pressure drops below 6 psi the gage will show 0.
- The information from the swiitch is not fed back to the PCM in any way and is to be used as a reference only.

The idea that this is a fuel shutoff is incorrect.

 

Well then it should be much simpler to connect an analong sending unit to the dash guage. Now to only find a source for this unit, which will fit with that AN fitting. Any ideas???
Lariat

 

Check out this URL, it lists some manufacturers, and P/Ns of analog oil pressure sending units:

http://rogueperformance.com/oilsw.html

 

Thanks Bob A and Choctaw Bob,
Do we know if these sending units depicted at the link are AN fittings? I know from prior converstaions about setting up with a by-pass filter that this was not your standard fitting like it use to be. I ass_u_me that we will need to get an AN type fitting to pipe thread to do this. Is this correct?
Lariat

 

The problem as I see it is that we also have to calibrate the gage even if it can be made to work. A high reading is how many pounds?

 

Seems to me, if the guage does indeed work, that you could put a temporary mechanical guage in line, get the reading, what is normal at idle and perhaps 2000 RPM. Long as the guage stays at those points, "pressure" is irrelivant. Well, it is, but it is nice to have the dash guage, actually fluctuate. I would expect you could "parallel a real pressure guage" with the idiot guage on the same sending unit. Might be wrong. Please correct if I am.
Lariat

 

I don't think that it's important that a particular reading on the gauge is "X" number of PSI. If you have a newer truck, what would be important is changes in the gauge reading over time.
This would indicate something was having wear (bearings, oil pump, plugged oil pick up screen, etc.).

 

Bob A,
That is exactly my thought.
Lariat

 

Any kind of oil pressure change is an indication of something going on inside the engine. For instance, on this message board there have been several that have reported engine over full of oil. This was caused by injector failure. The crank case full of diesel would have registered immediately as low oil pressure. Any of these engines could be subject to extreme bearing and ring wear in short order.

I have installed a mechanical oil pressure gage on every truck I have ever owned and on all race cars. I had an Auto Meter electrical sending unit fail that cost me a race. So I won't use anything but a mechanical gage.

I guess it's experience but as soon as I can (this week) I will get an AN pipe fitting to a 1/8" compression and mount the Auto Meter Oil Pressure gage beside the Auto Meter Pyrometer Gage that is already mounted. It doesn't mater what the dash gage reads.

 

If the oil line ruptures, or a fitting comes loose on a mechanical gauge, the results can be catastrophic also.

I do, however, have the OEM mechanical gauge on my Mercedes 300D, and it works well!!!

 

You just want to make sure the plastic line is not laying against the turbo housing - yikes!

I have had one copper line fail after 100K miles of oil field road. I like adventure so I always carry some tools!

 

I've posted my solution to Ford's oil pressure gauge before but it may be helpful to do it again. I removed the Ford pressure sender, it was an NPT thread, 1/4" if I remember correctly. I used an adaptor and a length of 300 psi hydraulic hose to reach over to the passenger side battery area where there is some room to work. I used a "T" threaded to the hose to accommodate the Ford sender and a Westberg oil pressure sender and gauge installed in an "A" pillar pod. I had to extend the wire to reach the new location for the Ford sender. I used a 1/2" all thread rod secured to the battery tray to mount the "T". Oil pressure is 60psi @ road speeds, 20 psi at hot idle and pegged at cold start up.

 

Good solution! You can always spot a Hot Rodder!