inaccurate fuel guage sender
Thread Starter
Melting Slicks
Joined: Oct 2010
Posts: 2,276
Likes: 337
From: "ɹǝpunuʍop", Adelaide, South Australia
inaccurate fuel guage sender
have just put a brand new tank sender in my 72.
but the dash gauge still shows under the full mark when filled to the brim.
so according to the willcox papers,
"For a fuel gauge from 1968-1976 to function properly you must
have 0 ohms when empty, 45 ohms at one half a tank and 90 ohms at full tank."
i have refilled the tank, and when filled to 1/4" under the fill tube,
i'm only getting 76ohms on a test meter between the sender pin and ground.
so does that mean that i'll have to remove the sender and bend the float arm down slightly to get a fuller reading?
also the pickup sock n tube appears to sit high in the tank, ie; leaving a fair amount of fuel behind at "empty"...
but the dash gauge still shows under the full mark when filled to the brim.
so according to the willcox papers,
"For a fuel gauge from 1968-1976 to function properly you must
have 0 ohms when empty, 45 ohms at one half a tank and 90 ohms at full tank."
i have refilled the tank, and when filled to 1/4" under the fill tube,
i'm only getting 76ohms on a test meter between the sender pin and ground.
so does that mean that i'll have to remove the sender and bend the float arm down slightly to get a fuller reading?
also the pickup sock n tube appears to sit high in the tank, ie; leaving a fair amount of fuel behind at "empty"...
Le Mans Master
Joined: Jun 2006
Posts: 6,400
Likes: 1,226
From: Tampa Florida
have just put a brand new tank sender in my 72.
but the dash gauge still shows under the full mark when filled to the brim.
so according to the willcox papers,
"For a fuel gauge from 1968-1976 to function properly you must
have 0 ohms when empty, 45 ohms at one half a tank and 90 ohms at full tank."
i have refilled the tank, and when filled to 1/4" under the fill tube,
i'm only getting 76ohms on a test meter between the sender pin and ground.
so does that mean that i'll have to remove the sender and bend the float arm down slightly to get a fuller reading?
also the pickup sock n tube appears to sit high in the tank, ie; leaving a fair amount of fuel behind at "empty"...
but the dash gauge still shows under the full mark when filled to the brim.
so according to the willcox papers,
"For a fuel gauge from 1968-1976 to function properly you must
have 0 ohms when empty, 45 ohms at one half a tank and 90 ohms at full tank."
i have refilled the tank, and when filled to 1/4" under the fill tube,
i'm only getting 76ohms on a test meter between the sender pin and ground.
so does that mean that i'll have to remove the sender and bend the float arm down slightly to get a fuller reading?
also the pickup sock n tube appears to sit high in the tank, ie; leaving a fair amount of fuel behind at "empty"...
To me, it sounds like the sending unit is not adjusted properly, or maybe it was bent before you installed it.
Melting Slicks
Joined: Aug 2005
Posts: 2,683
Likes: 34
From: Working on the car NY
My gauge is inaccurate in both my 1967 and 1969. The '69 FWIW also has a new sender. In fact 
the '67 stalled out on the street right in front of my house 2 years ago. I thought it was the plugs and embarrasingly replaced them right on the street. I car still didn't fire. Gas gauge read over half. Don't know why, but I checked the tank with a flashlight - dry as a bone. Put gas in and it fired right up
.
I now visually check the tank before I use it and use the odometer figuring how much I'm still good for. YMMV
the '67 stalled out on the street right in front of my house 2 years ago. I thought it was the plugs and embarrasingly replaced them right on the street. I car still didn't fire. Gas gauge read over half. Don't know why, but I checked the tank with a flashlight - dry as a bone. Put gas in and it fired right up.I now visually check the tank before I use it and use the odometer figuring how much I'm still good for. YMMV
Team Owner
Joined: Sep 2006
Posts: 31,285
Likes: 4,374
From: Westminster Maryland
Hi,
I found that the float on a replacement sender wasn't as buoyant as the original so I moved the old float to the new sender arm. It now floats on the surface of the gas giving an accurate gauge reading.
The end of the filter 'sock' rests on the bottom of the tank.
Regards,
Alan
I found that the float on a replacement sender wasn't as buoyant as the original so I moved the old float to the new sender arm. It now floats on the surface of the gas giving an accurate gauge reading.
The end of the filter 'sock' rests on the bottom of the tank.
Regards,
Alan
Le Mans Master
Joined: Jun 2006
Posts: 6,400
Likes: 1,226
From: Tampa Florida
Perfect timing on this thread. I just did a bench test on my new tank and sending unit. The screen sits on the bottom of the tank and the sending unit is reading 0 ohms, so hopefully it will read correctly when it is full of gas.
