Fuel Tank Differences

[brians]

I put a fuel tank from a 90 into my 84 F250 and the fuel gauge stopped working. After a little research I discovered the newer Fords (90 and up, I think) use a different sending unit and fuel guage and the two are not compatable.

I have attached a picture of the 2 tanks and the 2 sending units. The one with the larger sending unit hole is the 90 tank and the smaller one is the 84 tank.

My plan is to cut the mount off the 84 tank (plasma cut around the outer circle), cut the retaining ring off the 90 sending unit and make a hole in it, then weld the 84 mount to the 90 retaining ring. I can then mount the complete 854 sending unit in the 90 ring and mount the 90 ring (with the 84 sending unit) in the 90 tank.

I'll post some pictures as I go.

Brian

 

[towcat]

Here you got it folks...this is proof that Brian has been sniffing welding fumes way too long
he just doesn't believe me that these senders have a short life span and not worth the grief. But hey, somebody has to be the official lab rat around here. Not to mention, its good that he's getting welding experience on these feul tanks since he's gonna be welding in a container for the heat exchanger on my waste oil project

 

[typ4]

Why not just change the sender reostat from the old sender to the new tank unit, unsolder and resolder, hook up the wire, good to go. btdt

 

[highest_vision]

Well, I'm going to leave the fumes thing alone.... but a newer body style sender won't work, you're right. Their internal resistance is different. I think sufficiently different that they wouldn't even register a reading on your gauge. 83-86 were something like 70ohms empty, 10 full. 87 and up trucks were 15 empty, 160 full. And the newer ones were 12v.
James