Oil Pressure Guage Mod: V8 Engine Help

[V8BoatBuilder]

After reading the thread on the Oil Guage Mod, I decided to do it on my 97 Mountaineer with V8.

I think i have located the oil pressure switch (sender) on the engine, but can anyone confirm its location?

Also, what is the best way to get to it? It appears to be in a really tight spot.

What senders will work for the V8? I took the advice on the othert thread and purchased a sender for an 84 F150 with I6, but the sender looks HUGE and the Neihoff part # is different. The sender Autozone gave me:
Niehoff: #FF135C, OP24771

The inlet is 1/2" NPT, and the sender overall is 3 1/2" long and 2" in diamter.

Any advice would be great. Esp how to get to the sender on the 5.0 Block

Thanks,
Aaron

 

[Maniak]

That sounds like the right part....

I've noticed there are really only 2 oil pressure sending units for ford..

The small one.. which is "open" from 0 to 5psi.. and shorted from 6psi up...

the big one which is low resistance at higher pressure.. and high resistence at low pressure.. (I can't find my paper with the numbers on it)...

You do just litterally pull the old sending unit out.. and put the new one in.. Just remember to do something with that stock 20 ohm resister on the back of your dash.. If you don't.. it reads low and slow all the time...

I compared my last 2 sending units.. and the Neihoff part # didn't match.. but the others did.. I'm working on an install article (with pics) for the 4.0.. and hope to have close to 8 different part #'s (including fords) for the sending unit..

~Mark

 

[Opera House]

Sure would like to know

the resistance of that Neihoff unit. All the senders I've looked at were either 180 or 250 ohm units at 0 psi. I was thinking of making a little electronic conversion box so one of these units would work and adding some "negative resistance" so I dont have to remove the 20 ohm resistor.

 

[Maniak]

You dont' actually have to remove the resister.. You just want it bypassed... I have a wire across it...

You can see how your gauge reacts by using a POT.. to vary the resistance...

I did this when I was first testing out this mod..

I took the wire off the sending unit.. and put 1 end of the pot to that wire.. and 1 end to ground...

I then varied the pot to get my gauge to move....

I then measured the resistance of the pot to get an idea...

100ohm barely makes the needle move...
10 ohm makes it go all the way to the end of line.. (not off the scale)...

To know what it was going to do on my truck (my new sending unit) I ...

screwed a 1/4" npt quick connect onto my sending unit and plugged it into my air compressor.. and hooked it up to my sending unit... (gounding it to the truck of course)..

I then turned on my compressor and stopped it at different intervals.. I stopped it at 5psi, 10psi,40psi and 60psi... this gave me something to look at on the gauge.. now I know where the needle will be at 5psi, 10psi 40psi and 60psi... I was just curious...

the thing to remember is 20ohms is just a hair higher than 1/2 way up the scale.. 10 ohms is just about the the end of the upper scale.. and 100 ohms is just about to the bottom of the scale... so make sure the sending unit you have has specs that sound right.. (e.g.. chevy sending units run backwards compared to fords... I learned that one the hard way)..

~Mark

 

[Maniak]

Here is the autozone part that matches the sending unit I used this time...

Dead Link Removed|~S334|~1

you can compare the specs of this sending unit to the one you got..

~Mark

 

[V8BoatBuilder]

Went back to autozone - found the exact Neihoff P/Ns from the original thread.

The sender looks almost the same, still has the 1/2" inlet, but the body is a little smaller in Diam.

FYI, It cost $5.99 and was listed for a 87 F150 5.0 V8 with Guage.

I'm about to put it in, I'll try to snap some digital photos and do a write up. It seems strightforward, with the exception of actually getting my hand and wrench around the sender!!!!

-Aaron

 

[V8BoatBuilder]

Setbacks...

How the hell do you get into that cramped spot on the front of the V8?

And it looks like the sender body is too wide - it won't clear the block.

Other people who have the V8 - how did you do the MOD?

Thanks,
Aaron

 

[V8BoatBuilder]

bump.... still looking for advice on reaching that sender on the 5.0.

 

[Maniak]

Does this link help?


This article was written for Cobra Mustangs.. which I "think" had the 5.0.. but possibly the 4.6.

On the 4.0 motors the oil prressure sending unit actually plugs into a fitting that is then screwed onto the block.

Thie moves the sending unit away from the block a few inches. This may be what you need to fit the larger sending unit on the 5.0..

If you can't find that part, I think I have a blown 4.0l that may still have that part on it.

Edit: Lets try this again....
Dead Link Removed

~Mark

 

[V8BoatBuilder]

Mark,

The link didn't show up, but i d'll do a search for it. I'm going to try and find some 1/4" pipe and maybe that will fit it, but if that fails, the peice from the 4.0 would be great.

-Aaron

 

[Maniak]

I guess it helps if I actually put the link in the mesage...

I fixed it above.. and will post it here so people get notified of the fix..

Dead Link Removed

sorry about the cranial flatuence

~Mark

 

[Texan01]

My friends old 85 5.0 LX had an extension that moved the sending unit about 4 inches away from the block. you could theroetcially put it anywhere you wanted to with the right combinations of angles and straigh pipes.