I have a 1989 F250 w/ 7.3 IDI and dual tanks. I want to replace both tanks and I'm having trouble finding sending units for a diesel. Will the sending units for a gaser work? I know they will fit into the tank because it's the same tank for either gas or diesel. I noticed they sell gas senders either with or without a new electric pump. Is it possible that the senders without a new pump are to be used on diesels? Do the gas and diesels have the same electrical plug connector?

 

Gasser fuel pickups will actually not fit in diesel tanks, not without some mods at least, for one the locating tabs are 180* off IIRC. Either way, why you wanna replace the pickups? The ones in our trucks have no fuel pumps on them (cause the fuel pump is on the side of the engine, like a carbed gasser) and don't really go bad unless rust eats them, what does fail is the sender unit float (develops pinhole leaks, fills up with fuel, and sinks to the bottom of the tank), the sender unit itself (the contacts wear out and cause erratic readings), and the pickup shower head at the bottom of the tank (falls off, cause truck to run outta fuel at 1/4 tank) - all of these are replaceable separately, and there's no need to buy the whole big expensive assembly when all you may need is just one part of it... So, what's the issue with what you have in there now?

 

While I have not done a side by side comparison of a tank removed from a diesel and one removed from a gaser, the part number when ordering a replacement tank is the same (gas or diesel). Further reinforcment of this assumption is the fact that most descriptions for these tanks state they will work in either gas or diesel. This leads me to believe they are the same. With that said, you can logically conclude either of the senders will fit in these tanks.
The reason I want to replace both senders is because they have erratic readings. They read "Full" till the tank is all but empty. AND Since replacement of these parts requires a fair amount of de-construction, I'd like to replace them with new to avoid the possibility of having to tear it apart again!
Does anyone know if the electrical plug-in is the same on both gas & diesel???
Another group that may have answers are the guys who have done gas to diesel swaps or diesel to gas swaps.

 

pretty sure the gas and diesel senders are different. I would think partsguyed.com should be able to get you OEM senders for around $85.00 each.

 

Sounds like more of a wiring issue than a sender issue.... if there is a break in a wire, or a short, it will give you very strange readings. Since you have dual tanks, you can run off one for a period of time while you work on the other. I would be tempted to pull one tank at a time, and do some looking to see what is going on. It could be something as simple as a PO having the tanks out and bending the sending unit arms the wrong way or something affecting the readings.

I learned long ago I don't rely on fuel gauges, I fill the tank, and keep an eye on the distance driven to know what I have available to me before needing a fillup.

 

Still looking for someone who can answer the question! "Will my diesel wiring harness plug into a gas sending unit"? OR "Does anyone know where replacement diesel sending units can be purchased"? I tried the suggestion previously mentioned regarding website partsguyed.com and it doesn't work (nothing comes up).

 

www.partsguyed.com Here is a link to partsguyed. I think he should be able to help.

 

May be just the Bronco tanks then, as when I was installing mine I had to jump through hoops to make the diesel pickup unit fit like it should in it. If the regular pickup tanks say they work both for gas and diesel, then they probably do...

Here's the thing with the connectors - the pickup you need for your diesel truck has 3"-something base diameter, the only gasser pickups with the same size of base are those with the pumps inside the tanks and their harness connector is way different - gasser pickup assemblies that have no pump on them may have the right connector, but they also have a base of about 2" and will clearly not fit your tank. I'd imagine you can both a tank and a pickup assembly for non-EFI truck (so those with the 2" base), but I'm not sure if those would have a proper size. IIRC the sender units are identical between my '90 IDI and whatever EFI gassers I found at the junkyard, I measured my diesel and two gassers and they all had the same resistance values when empty and full - I know one of my senders dies I will be swapping in one of these good gasser sender I have now, may not be a 100% drop-in swap but they sure as heck look close enough to where they'd work with minimal mods...

 

The link worked! After entering the appropriate information for my truck it came up with a sending unit description that did not specify front or rear. This tells me the sender is simly that, "just a sender". Meaning its a repair part for my current in tank assembly. I would rather buy the entire in tank assembly.

 

Yes, the front and rear sender units are identical, it's the pickup assembly they're mounted on that's different...

 

This sending unit thing has been a real journey! Nobody has them (at least I cn't find them)! Plenty of gasser units at various prices but no diesels. So here's the plan, I ordered two replacement "Poly tanks" each are 19gals. My plan is to remove the bed, and remove both tanks. During replacement I'll order a new "gasser" sending unit (without pump) from Advance auto parts here in town. While I have the diesel sending units out, I can compare and see the differences with my own eyes. If there's significant visual differences, I'll simply return it. If it looks like it will work with minor mods, I'll gamble! I'll let you know what we find.

 

As promised, here's what I've learned. Bed is off. Leaky tanks are out. Diesel sending units are out of the tanks & testing reveals neither one works correctly and since they are badly corroded I plan to replace them. Since I've been unable to locate complete replacement diesel sending units, a gaser sending unit was purchased for comparison to the diesel unit. It should be noted there's only one tank style and it's designed for both fuel types and both sending units fit into this tank. The differences between the two sending units are: #1. The electrical connector plug for the diesel has two pins and the gaser has 4 pins. #2. The gaser sending unit is designed for an electric"in-tank" fuel pump, so eliminating the pump for use in a diesel will require lengthening the pick-up tube. Now for testing, with the gaser sending unit simply laying on the rear tire, I used jumper wires to connect it the diesel two pin electrical plug. The gaser sender works! When I move the float to full, it reads "full" on the diesel gauge, and when I move it to empty, it reads "empty". Next I needed to find a way to make a "nice" electrical connection. Since the diesel plug doesn't fit, I clipped it off and purchased a new gaser 4-pin plug from NAPA (pn# ECH FPC100) price was 8 or 9 bucks ea. Yes it has 4 pins but I only need 2 for the gauge so the other two are empty.

Hope this helps somebody and if I knew how to post pictures, I'd send some.