Tech write up: gmt800 fuel sending unit retrofit

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Location
Everywayah, Maine
First Name
Nick
Truck Year
1978
Truck Model
K10
Engine Size
5.3
So let me start off by saying that I wanted to use as many parts from my 2001 donor truck as possible. I realize that you can use a factory sender with an ep381 pump, but I already have a good gmt800 sender in the garage. If you don't feel like buying a new sender and a new pump, and you know someone who can build these rings for you, this is certainly an option.

Upsides to this swap are these sending units being way more common second hand (in my area at least)
The technology is newer
No clamps inside the tank
The sender isnt going to rust
And it has the same quick disconnect fittings as the fuel rail.

The only downside is that to build these rings you really either need a lathe or a plasma table.

Note:The sending unit will not retain the fuel level sender. I wanted to use an aftermarket fuel gauge to get rid of the huge one in the cluster, that way I can retrofit my autometer tachometer in.

I started out with 3/8 thick mild steel for the bottom ring. The OD is 6.00 and the ID is 4.00
I center punched the center of the plate. Drilled it to 1.250, and started by getting the size scribed on the plate

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Why cant the sender portion be used also?
 
Joined
Jun 29, 2015
Posts
38
Reaction score
1
Location
Everywayah, Maine
First Name
Nick
Truck Year
1978
Truck Model
K10
Engine Size
5.3
After cutting the original ring out, I got this one welded in

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Quick disconnect an fittings installed
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Installed!
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