Fuel sender unit - what to use in NWMP aux fuel tank (1 Viewer)

[Source3]

I am trying to figure out which fuel sender unit to use in my planned purchase of this aux fuel tank from Northwest Metal Products - Since 1977. I am following bsevans setup (https://forum.ih8mud.com/40-55-series-tech/84831-man-fre-auxillary-tank-question-4.html#post3348360) and will be purchasing this switching valve Light Truck 6-Port Motor Driven Valve on Pollak so I can use my stock fuel gauge (9/72) for both the stock main tank and aux tank. The stock fuel gauge is reported to require 120 ohms empty and 17 ohms full (have not tested my gauge, just what I obtained from reading).


From a comment from bsevans and genesmith5720 at https://forum.ih8mud.com/40-55-series-tech/136807-conferr-aux-tank-internal-layout.html#post1838771 (referring to the Conferr tank; similiar design to the NWMP tank), it appears they both used a modified stock fuel sending unit.

The tank is baffled, but it will not interfer with the fuel gauge sending unit if it is installed on the left side of the tank (I do not know what the right side looks like inside of the tank). The baffle I can see is more towards the center of the tank. I had to weld an extension so the sender would operate properly.

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Does anyone have words of wisdom or pictures of a modified stock send unit?

Others have reported using UNIVERSAL FUEL LEVEL GAUGE SET FOR ALL 12-VOLT NEGATIVE GROUND SYSTEMS - JCWhitney, but I think that the fuel gauge that came with the kit was used?

Other suggestions are welcomed. I do not want to add another gauge as I do not want to clutter up the dash by adding another gauge.

Thanks.

 

[Downey]

After the Con-Ferr tanks were discontinued, we sold the NWMP tanks until we made our own fuel cell (at which time knowbody wanted the NWMP tank). When we did sell the NWMP tank, they never installed a hole for the sending unit, so we drilled our own holes before delivering the tanks. We drilled for a factory sender (120/17 ohms in your case). As I recall, we drilled on the right (passengers) side of the tank, 5" back from front wall of the tank to hole center, then far enough to the right side that the float would be near center (most ideal location) but not hitting the center baffle. Also, indexing on the bolt hole pattern had to be such that it pointed the float off into the correct direction. With our nylon seamless fuel cells this is not a problem because we use a trick digital sender (probe) that mounts into our aluminum panel, in a location on the center line pre-determined by us. Hope this info helps.

 

[Source3]

When we did sell the NWMP tank, they never installed a hole for the sending unit, so we drilled our own holes before delivering the tanks.

After I figure out which fuel sender to use, I can send the unit to NWMP and they will drill and install the sender. NWMP still ships the aux tank without any holes for the sender.

 

[Source3]

Ok, I am in the process of ordering a NWMP tank. The next step is to order the sending unit. It appears that I can order a stock fuel sending unit for a 1973 FJ40. Then bend the rod to the float to accommodate the depth of the aux. tank. If needed, it looks like I can weld on extra length to the float rod.

EDIT --> Just found this link: https://forum.ih8mud.com/40-55-seri...put-fuel-sender-maf-aux-tank.html#post4146746 discussing adding length to sender rod.