So if bending the arm doesn't give enough span, then you can adjust the gauge so it tops out correctly?
Fuel Gauge/Fuel Sending Unit issue
- Thread starter sleepycruiser
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sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #22
So I need to bend the arm down I guess.
Mine is the different newer type, but the principle is the same, so yes.
The actual sensor has a certain range, but the arm can only cover part of that range because the fuel tank impedes its movement.
Obviously there's only so far you can bend it, and if you test it outside of the tank, then you have the full range of motion anyway.
The actual sensor has a certain range, but the arm can only cover part of that range because the fuel tank impedes its movement.
Obviously there's only so far you can bend it, and if you test it outside of the tank, then you have the full range of motion anyway.
sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #24
It is weird that both the old and the new one are acting the same. I’d think that the new one would have been set up correctly. Maybe the gauge gets ‘tired’ over the years? No idea.
@sleepycruiser did you ever get this sorted out? Dealing with something similar on my 70’ and have yet to get it resolved. Thanks!
My 72's fuel gauge has never been right since I got it in 82 (reads past F for a long time, then quickly drops to 1/2, might be "on or not" until E which is correct. Used odometer as a better indication of fuel/distance. Added a 12.5 gallon aux tank from Datsun B210. Managed to balance the resistance so the aux tank would read from 1/2 which is full to E which was empty on the gauge.
sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #27
I haven’t figured it out yet. Someone suggested bending the metal arm to change the float location but I haven’t tried that.
Kayaker
SILVER Star
When I purchased my LC in 1972, the gas gage, like that of Charliemeyer007 above, would read above full when full, they would slowly make its way to half a tank over the next 200 miles of driving. When it hit the 1/2 mark, I could drive 50 miles until it was dead empty. Over the years I got accustomed to it and would start looking for gas at the half tank mark. Interestingly enough, I pulled the tank in 2012 to look for rust in the floor pan and the bottom of the tank, seemed prudent after all those years. Having drained the tank, I painted it and the floor board, and reinstalled it. After that, the gage read correctly for the first time ever! What a shocker! I guess all that movement in the sensor arm with the tank dry did something to free it up. Anyway, just recently, it has started acting up again. Shows full after a fill up then drifts slowly down to just above full where it sits until I drive a hundred miles or so then it starts tracking the actual volume. No idea what's up now but I'm just watching the odometer and waiting to see if it corrects itself. If I get aggravated enough, I may pull the tank again and toss it around to see if it heals itself again., or I may invest $125 in a new sender unit. Ah, the joys of Cruiser ownership.....
sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #29
What is weird is that I put in a new sending unit and it had the exact same symptoms of not showing the correct fuel amount…so I took it out and put the older one in. They reacted the same. I grounded the sending unit and the gauge went all the way to full so I’m not sure what the issue is.
As with the majority of FJ-40 electrical issues seem to be, BAD GROUND!
sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #31
I’ve checked the ground on the sending unit and the gauge and neither made a difference. Anything I’m missing beyond that?
Checking to see if a ground wire is present is really not enough. You need to remove the wire, clean the mating surfaces which could be as simple as wire brushing but sometimes involves sanding to remove paint or heavier corrosion.
Most of life’s issues actually.. most cars.. most house wiring funky issues (“loose ground/neutral”) Yelling at your wife(husband) kids or dog… road rage… your likely not well grounded!
sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #34
Thanks for the info. I ran a separate ground from the sending unit and I did from the gauge as well just to test. When it gets a little warmer I might take another stab at it.
Worth checking the fuse and the feed all the way through to the gauge also.
They're a funny thing because of how they work. A bad connection anywhere in the loop can mimic the sender to some extent as it warns up
They're a funny thing because of how they work. A bad connection anywhere in the loop can mimic the sender to some extent as it warns up
Kayaker
SILVER Star
Just for fun, I disconnected all the wires from my sending unit, then cleaned and reattached them. No change. Did the same on the dash gage; pulled the dash, cleaned the contacts and reinstalled. Again, no change. I then ran a ground wire (like Sleepycruiser) directly from the battery to the sending unit but still the gage reads 3/4 tank when full. The one thing I haven't done, is run the tank almost empty to get the float to fall as low in the tank as possible, before filling up. Ever since the gage started acting up, I've filled up well before the tank is empty. If that doesn't work, looks like a new sending unit may be in my future.
sleepycruiser
I will get by….I will survive -Touch of Grey LC200
- Thread starter
- #37
I’ve also been told that bending the float wire (down I think) could manipulate the tank into correcting since the float would be higher up when it has gas…but I’m not sure.
