Repairing tube fuel sender unit?

[KMW]

Hi, I have two tubular fuel sender units neither of them working.
Does anybody know how to dismantle these?
Was thinking of trying to repair them before buying a new one.
After all they are broken already, can't get any worse.

/Anders
Charlestown

[skills@eurocarsplus]

what year bay, and what exactly is wrong? i rebuilt the sender in my 70 single scab. i will tell you what i did, maybe it will help

(i am a early bay guy, so i am unsure if anything past 71 is the same)


ok, assuming that you have the unit in your hand (and it looks like a 68 to 71 sender ...again i don't know what a 72 up looks like) what you need to do is carefully fold over the lock tab washer doo dad that holds the tiny nut from backing off. i think the nut was a 4 or 5 mm. take the nut off, and CAREFULLY pull the tube off. you may need to gently twist the tube a bit, but i think there is a notch that won't let you spin it all the way around. either way, go ez with it.

once you get it off, you will see a THIN wire that goes from the top of the sender to a 'T' at the bottom, and returns back to the top of the sender. look at the shaft, and make sure the float slides freely. look at the float, you will see contacts on it. carefully, clean the contacts that ride on the thin wire, and make sure that the contacts touch the wire when you are done cleaning them

my problem was i had a bad connection between the unit and ground. if you look, you will see the signal wire to the gauge passes thru the body of the sender, thru fiber washers and is rivited to the unit. the rivit makes the ground for the gauge by keeping the tail end of the thin wire grounded to the unit. (it will be a coil looking brass/copper ring you are looking for) it was near impossible for me to get under it to clean and retain enough spring tension to make a ground, so i cleaned everything real good and soldered the brass/copper ring to the body of the sender.

holy hell it worked just be real careful not to over heat the solder area, you don't want to get the wire too hot. you need to move with surgical precission with the whole operation to have any luck.

i never took pix of my repair. if you get it apart and post pix, i will photo shop them with discriptions of what i needed to do to make it work.

hope it helps

[KMW]

Mine is a 1960 Karmann Ghia Convertible.
58-60 KG had a unique fuel sender, before there where no fuel gauge.
After (61-) it's the same float on pin as in the beetle which got a fuel gauge in 1961.
58-60 KGs use a standard VDO tube sender with VW logo similar to what is used in bays.
That is why I asked here instead of in the KG forum, much more likely to get an answer here.

I've loosened the tiny nut, no looking tab on mine, but the tube won't fall apart.
No surprise since it has been assembled for 50 years!
There is a notch which stops you from wiggling it more than a fraction.
Before using force I wanted to know exactly how it should split.
I know the basic layout inside and I think the problem is corrosion.
Grounding is not the problem, besides I've mounted an extra grounding cable to make sure of good ground.

If I get it apart I will take pictures to show how it looks and what can be done.

Thanks for the help so far, Anders

[regalasr]

PM Icy. He fixes the tubular senders. At least he used to.

[busfreak_71]

You usually need new resistance wire. Tricky to find the right stuff. I know I need a new sender in my '73.
_________________
'71 Tin Top Westfalia
'99.5 Bora TDI
'85 Jetta Coupe
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Resident Off-Grid hippie and diesel advocate.

[foxtail1]

Some times the wires get gunked up. I fixed my by just cleaning off the two wires. Also check the contactors you might have to bend them.
_________________
As they say, "You never know until you ask the question."

64 bug
64 bus
59 ghia
71 bus

[SGKent]

my experience with these is that the wire and contacts wear and corrode. You can clean them but in a few months they will be bad again. I went through this on my 1971 several times in 350,000 miles. My suggestion is to contact any of the vendors like BusDepot as they show the tubular style available.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[foxtail1]

Use a detergent gas....

Just being a smart ass.....That is good to know.

Thanks..
_________________
As they say, "You never know until you ask the question."

64 bug
64 bus
59 ghia
71 bus

[KMW]

Sweden is not a county in Minnesota but a country in Europe.
Sending the unit twice over the Atlantic to have it repaired is not an option.
I will try to repair it, only costs some of my time.
If that does not work I'll get a replacement from an European dealer.

Thanks for the advices, Anders

[60ghia]

I took my tubular sending unit apart and had to resolder the thin wire to one of the contacts. Unit seems to work fine now.