I have a 86 E350 cutaway with dual tank and the front gage is reading Empty regardless of the fuel level in the tank.

I'm looking to troubleshoot the problem but the wiring colors in the Haynes are not the same as on the truck.

I found another diagram and the colors aren't the same too.

I would like to test my wiring before dropping the tank and can't find the right colors to test the fuel sender.

The wiring from the front tank has a green, brown and couple of black wires.
Also the fuel selenoid valve has 5 wires (red, green, green, brown, orange)
I can't find these colors on any diagrams.

Thanks for your help.

 

What engine do you have?
Is this an RV?
Is it FI?

This one matches your colors:
http://i54.photobucket.com/albums/g91/subford/Fuel/1987FuelpumpselE1505.gif

 

It's a Motorhome with a 460 carburated.

I looked at the drawing you posted and I think you have the right one!

I'll check this afternoon with my meter to spot my trouble.

Thanks a lot.

 

You more than likely can use that diagram for wire colors to check out your gauges but I think that one is for a FI Van.

Here is one that I would think would be wired the way yours is but the wire colors are wrong for your year. This one is for 1983 and 1984 460 carbureted with the hot vapor bypass.

http://i54.photobucket.com/albums/g91/subford/Fuel/1983FuelElCT.gif

 

Thanks but I already had this one.

The first you sent has the exact colors for the switch and the selenoid valve.

I ran my tests yesterday and the results with the connector at the selenoid unplugged were:

rear tank - full - sender reads about 18 ohms.
front tank - empty - sender reads about 70 ohms

I also received at the plug, the pulsed 5V.

I went to the gas station and fill the front tank and took another reading on the front sender. That time it reads open circuit. The gage is still marking empty.

I'm now almost certain that the problem is on or in the tank. I will have to drop it.

 

I drew that one for a guy with a 1983 F250 but other than the wire colors it should be wired like yours.The senders should read:
73 ohms Empty
22 ohms half a Tank
10 ohms Full Tank

Open wire (disconnected) from the gauge the gauge will read the same as it does with the Ignition Switch off, Below Empty.

Grounding the wire from the gauge the gauge will read more than full.

 

Thank you SubFord. and others.

As I wrote above, my tests ran on the senders told me that the gauge itself works OK but the sender in the front tank is not responding. Its reading is good for the empty position but when the tank is full, sender doesn't give the good resistor value.