Fuel Gage Not Working: How Bad Are They?

[lotzagoodstuff]

Good evening. My front tank has never read anything but empty since I bought my truck and although I never run out of fuel, I am getting most of the other small things fixed so I figured I would tackle the non-reading gage. I am assuming that it's a sending unit issue and after doing a quick search on sending units, and it sounds like even brand new replacements are pretty crummy. I think I can get to the sending unit without pulling very much out, and if I can get the full and empty resistance values, I can even test the fuel gage by plugging in a couple of resistors to see if the gage moves properly.

My real question is: if I do all this and end up fixing or repairing the gage, how long can I expect it to last?

As always, any input is appreciated.

Thanks

R. J.

 

[subway]

well i just did the rear tank on my 94 and could only find the sender from ford. it cost me about $150 for the sendor and $20 extra since they decided to change the connector so i had to solder the new one in. i had to drop the tanks but you should be able to get the midship one out without dropping it. mine would always read empty also, so it sounds like your sendor is bad. does your gage work with your other tank? if so that would rule out the rest of the wiring.

from what i have heard from others is these things have a limited life span and putting in used is a real gamble.......i cant personally vouch for that though, but makes sense.

these are the values i found when i searched for them. 158 ohms verses 16 ohms empty

 

[Agnem]

You will need to confirm that it is the sender. The tank selector valve can cause an empty reading as well. Pull the plug on it, and ohm out the sender.

 

[lotzagoodstuff]

Yes, the rear tank reads fine so what I usually do is track my front tank mileage from full down to 1/4 tank and then switch, but sometimes I forget and the misses is always questioning when we are going to run out of fuel . Mel, can you tell me what the full and empty values should be ? Yes, it is full right now which will make anything I do a more messy/stinky job .

Thanks again

R. J.

 

[lotzagoodstuff]

Sunken Float

Thanks to all for the tips on pulling out the sending unit without dropping the front tank, not too terrible a job at all. Upon pulling out the sending unit, I see that the plastic float is cracks and thus my tank is always reading empty. I measured the resistance of the sending unit and although it jumped around a little before I cleaned it, it reads 16 ohms empty and 170ish full. Cleaning it with brake cleaner definitely helped.

I looked online and it looks like all the Ford floats are pretty similar, even back to the 60s on carbureted cars. I do not want to put a plastic one back in, does anybody have a part number or source for a brass unit? I think I am going to end up at the dealer as the local parts stores can't seem to understand that I just want the part on the end of the rod, not the complete sending unit.

Thanks

R. J.

 

[flatlander]

Well just FYI, if you decide to buy and install a fuel pressure gauge instead, it will NOT fluctuate until app. 20 seconds after your engine runs out of fuel and dies.

 

[Michael Fowler]

In checking my Ford Parts Book for 1960-1964, it appears that Ford does NOT service the float apart from the sending unit.
The nice thing about Ford parts numbers is that they follow a fairly simple system.
First is a prefix that gives the year, and vehicle line. Ford uses a letter to denote the decade (C=1960, D=1970, E= 1980,F=1990 etc), the next number is the year of that decade. i.e. E9TZ would be a 1989 Truck line part.
The second group of numbers is the basic part number, all fuel sending units have a basic part number of 9275.
The last part is a sufix that gives changes, or other differences. For instance all frames have a basic part number of 5005; the suffix will be used to differentiate wheelbase, and or how heavy duty it is.

Anyway, There is no part number for the float, the sender only is listed. Therefore I doubt that you will find any help from a Ford dealer.
You could use cork for a float. Manufacturers used cork for years

 

[poolguy]

For what its worth, several of my small engined equipment use a brass float.
Perhaps a small engine shop could help.

 

[lotzagoodstuff]

Brass Float

Thanks for the information, I have found several that look correct online, all of these appear to be very similar to what I removed:

All of these links look really close, one is for a mustang and one is for a first generation F100:

http://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000016a~Z5Z5Z509955~P5.95~~~~~~~F

http://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000021f~Z5Z5Z565054~P7.50~~~~~~~F

http://store.cal-mustang.com/showdetl-7-6234-21-0.html

I have also found a part number that reads COAZ-9202-B which I am going to call the local dealer with tomorrow:

http://www.gudim.com/ReplacingCorkFloats.html

I will post pictures and confirm a part number and price if I get one.

Thanks

R. J.

 

[dwaymar]

Go to NAPA and look in the help section thats where i got mine for under 6.00

 

[Diesel JD]

I was going to say that I thought someone had gotten a replacement float at NAPA, but i assume it was just a plastic float as was the original? Also it seems someone had switched out the entire sender assy for an older style Ford vehicle fuel tank...but I can't remember who that was...I know he was on the Diesel Stop years ago, and I don't remember if he ever switched over here or what mods he said you had to do...the stock units do suck though...my newish sending unit still shows empty when I really have 7 or more gallons left in the tank....similar to the old unit except the old unit sorta jumps all over the place except when its full or empty. Anything just about would be an improvement....

 

[rkpatt]

I jsut found this thread after posting a similar one . Front tank has been pegged above F for a couple of years. This just happened wiht to rear tank . I will check both of the sending units with an ohm meter . If they are bad, is there anything (like a universal from JC whitney etc ) else I could using other than the $150 +Ford units .

Also what is the best option to access the rear tank sending unit ? Remove the tank or the bed ( procedure ?)

Thanks

 

[lotzagoodstuff]

Correct Float Part Number

Replacement float number is COAZ-9202-B, $4.77 dealer cost, about $11 retail, brass construction, appears to be the same for many other years of Ford vehicles.

Truck is repaired and reading fuel correctly.

R. J.

 

[subway]

I jsut found this thread after posting a similar one . Front tank has been pegged above F for a couple of years. This just happened wiht to rear tank . I will check both of the sending units with an ohm meter . If they are bad, is there anything (like a universal from JC whitney etc ) else I could using other than the $150 +Ford units .

Also what is the best option to access the rear tank sending unit ? Remove the tank or the bed ( procedure ?)

Thanks

not that i have found, it hurt coughing up the money but it is nice to have a working tank again. i think cheeper jeeper was going to play with a generic from jc whitney but i haven't heard anything.