Fuel Gauge Calibration

[AndyB.]

Yes, just lights aside from the fuel gauge.

 

[4x4prepper]

What did you use as a test bench voltage , 13.2 v ?

 

[AndyB.]

What did you use as a test bench voltage , 13.2 v ?

13.8v

 

[Bronco648]

I zeroed the trimmer on the instrument voltage regulator until the needle was on F.

I clearly need to do this as my fuel gauge reads well above F when the tank is full.

That said, is it easy to find the IVR? And, is the "trimmer" some sort of adjustment screw on the IVR?

TIA

 

[AndyB.]

You’ll have to remove the gauge cluster to access the IVR. The trimmer is the little screw on left above the post in this picture.

when disconnecting the IVR electrical contacts, use a small screwdriver to pry—don’t pull on the flexible printed circuit board.

 

[Bronco648]

I'm guessing the IVR is attached to the back of the instrument cluster?

 

[AndyB.]

Yes. Here’s a picture from an eBay listing. The IVR is above the wiring harness connector.

 

[Bird76Mojo]

Could a fuel gauge be calibrated close enough by filling the tank and then adjusting the IVR until the needle read a hair over full? Right now my 85 is WAY off. It's empty when reading 1/4 tank and read way over full when you top it off.

Nevermind. I did it and it worked fine. Though the oil pressure and the water temp seem to read lower now as well. That could be a sender issue though since this truck has been through multiple hands and god knows what parts were used after the engine rebuild. I suspect it needs the same oil pressure sender that I used in my V8 Ranger to make the gauge read in the middle.

 

[Bronco648]

That could be a sender issue though since this truck has been through multiple hands and god knows what parts were used after the engine rebuild.

I tried three different sending units and installed an oil pressure gauge (which I believe came with the truck). The electrical units always read in the lower part of the scale. The pressure gauge read 60+ psi except when the engine was really hot (like when I was trying to diagnose a failed electric choke). I removed the pressure gauge because it wouldn't stop leaking and I was afraid the cheap plastic oil line would pop out and the oil would exit the engine. None of the electric sending units leaked even though they seemed to read low. Maybe a braided steel line and that Bosch pressure gauge is a better solution. At the time, I had other fish to fry. I was also using the oil viscosity that the engine rebuilder recommended. As you opined, a thicker oil might be in order. HTH

 

[Bird76Mojo]

I tried three different sending units and installed an oil pressure gauge (which I believe came with the truck). The electrical units always read in the lower part of the scale. The pressure gauge read 60+ psi except when the engine was really hot (like when I was trying to diagnose a failed electric choke). I removed the pressure gauge because it wouldn't stop leaking and I was afraid the cheap plastic oil line would pop out and the oil would exit the engine. None of the electric sending units leaked even though they seemed to read low. Maybe a braided steel line and that Bosch pressure gauge is a better solution. At the time, I had other fish to fry. I was also using the oil viscosity that the engine rebuilder recommended. As you opined, a thicker oil might be in order. HTH

I still think I'll look up which model of oil pressure sender I used on my V8 truck and install one of those. It got the gauge to read in the center. Glad to see you're still on here. Are you still in the Ranger/BII game? Looking at buying another one?

 

[Bronco648]

I still think I'll look up which model of oil pressure sender I used on my V8 truck and install one of those.

I have owned a bunch of Mustangs in my day and recall the oil pressure sending units from the 289/302. IIRC, its the same unit as the one that is (was) on the engine currently; Standard Motor Products, PS60. Even the Motorcraft part number is the same; E6ZF-9D290-CA. Maybe I got three duds?

Glad to see you're still on here. Are you still in the Ranger/BII game? Looking at buying another one?

I now own a 2011 RCSB 2.3/auto in Oxford White. Just installed a sliding rear backlight on it over the weekend.

I could use some bodywork. If you know of any white doors, tailgate or even a bed, let me know. I'll drive down and get them. None of those items, that are currently on the truck, are rotten but they're starting to rust and I would like to replace them eventually.