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Premium Member
124 Posts
Discussion Starter #1 (Edited)
This thread is not completely done and I will add to it to get it completed as soon as I can.

If anyone has been inside of their fuel tank and found that the fuel sending unit rods were rusted and flakes of rust are falling into your fuel sending unit, I came up with a replacement procedure that replaces the stock steel rods and spring with stainless steel rods and spring that won't rust. You can purchase the materials yourself or I can put together a kit for you that has the parts needed to do the swap. If you are interested in the kit you can PayPal $26.00 along with your address to [email protected]

Below pic: Replacement kit stainless steel fuel sending rods,stainless steel spring and stainless steel retaining washer.

Step 1) Remove the fuel sending from the fuel tank.

Below pic: fuel sending unit removed from fuel tank.

Step 2) Look at the stock fuel sending rods. One has a spring and the
other side does not. At the bottom of the rod with the spring take note
that it has a notch cutout that has been turned outward to form a tab.
This small tab of metal is what holds the rod from slipping through the
bottom half of the fuel sending unit which holds the top and bottom
sections together.

Below pic: close up of small metal tab on rod w/spring.

Step 3) Using a pair of needle nose pliers grasp the small tab and
break it off or bend it down flush with the sides of the rod. This will allow both rods to slip through the holes that
hold them in position in the white plastic section of the fuel sending unit. Now the top and bottom are not connected
with the rods anymore the top and bottom are still connected with the
fuel sending unit wiring. Just don't get it all twisted up. Other than
that no worries.

Step 4) Once you pull the stock rods through the holes take an electric
drill and place the end of one of the stock rod into the drill chuck and
tighten the chuck on the stock rod. Now hold onto the top (yellow part)
of the fuel sending unit and run the drill at high speed.While running the drill the
rod will turn and once it heats up from friction you can pull out of the
yellow plastic sending unit top. So,once it starts to turn pull the
sending unti top away from you. This can be done by yourself,but is
easier with two people. One running the drill and one holding the
yellow part of the sending unit.

Below pic:

Below pic: Fuel sending rod removed using drill.

Step 5) Repeat removal steps above on the other stock rod to remove it

Step 6) Now you are ready to install the stainless rods.You will need two stainless rods, one stainless spring and
one stainless retaining washer provided in the kit. Take special note that the rods are
slighty different. One is just a plain rod. This plain rod mounts on
the fuel sending unit side without the spring. The other rod has a
small groove at one end. When installing the rods do not place the
grooved end into the yellow top of the fuel sending unit as this
grooved rod has to have the groove facing towards the bottom of the
fuel tank and sending unit.

Step 7) Using a heat source heat the end of the stainless rod. It
doesn't have to be glowing red hot,but hot enough to slightly melt the
plastic when you push it into the yellow part of the fuel sending unit.
I use a propane torch and only heat for 20 seconds. A large
candle probably will work to get the
stainless rod sufficiently hot. Once the rod is hot,push it into the
plastic sleeve on the yellow part of the sending unit that you removed
the stock rods from. While the rod is pushed into the sleeve hold it in place
until the plastic cools.It takes about 30 seconds. Don't get it too hot and push it in too far or it may melt clear through the top of the sending unit. Now check to see if the rod is going to hold
into the plastic by pulling on the rod. If it pulls out of the sleeve,
reheat the rod and repeat the above step. Repeat for the second rod.
Double check to make sure the rod with the groove has the groove
towards the bottom and is mounted on the side that has the spring.

Below pic: heating stainless steel replacement rod.

Step 8) You now should have both stainless rods mounted firmly into the
yellow top. You can loop the three fuel gauge wires around the rod as it was when you disassembled the unit. Its not necessary,but gives a neater look. Now slide the stainless spring onto the rod with the groove and line up both rods so you can slide the rods into the plastic
sleeves that are on the outside of the white bottom part of the fuel
sending unit. Once both rods are into the sleeves turn the fuel sending
unit upside down. Press down on the sending unit to compress the
spring. Now you need to place the retaining washer onto the stainless
rod with the groove. This is probably the hardest part of the whole
project. Place the retaining washer in position with the concaved side towards the bottom of the fuel sending unit. This will let the retaining washer get a better bite on the groove. Once the retaining washer is installed and you test the fuel sending unit for proper movement sometimes the washer will move up and down on the rod. This is okay as it still won't go past the groove. Using a nut driver push down on the retaining washer until it locks into the groove on the
stainless rod.

Below pic: shows correct orientation of retaining washer on grooved rod. Make sure the cocaved side faces the bottome of the fuel sending unit when installed on the grooved rod.

Step 9) Check the fuel sending unti for proper operation. Move the top
and bottom up and down compressing the spring and releasing to make
sure the fuel sending unit will have upward tension on it when
reinstalled into the fuel tank. The retaining washer may move on the rod,but it will not go past the groove at the bottom of the rod. See below pic.

Step10) Reintall the fuel sending unit into the fuel tank. Paying
special attention that the supply (black) and return (blue) fuel lines
on connected to their correct fuel sending unit fitting.

4 Posts
fuel tank sending unit

hi there, just wanna ask whats the use of fuel tank sending unit?how it works? and how to replace it?thanks in advance.

Premium Member
124 Posts
Discussion Starter #3
hi there, just wanna ask whats the use of fuel tank sending unit?how it works? and how to replace it?thanks in advance.
The fuel sending unit serves a couple of different functions. 1) it contains the float and fuel gauge sending unit that tells the dash gauge how much fuel is in the fuel tank. 2) pumps fuel to the fuel filter from the fuel tank. The fuel sending unit is located in the fuel tank and found under the rear passenger seat on a good number of the VW models. Most models have either a metal or plastic cover that you have to remove to access the fuel sending unit. There are two fuel lines and one electrical connector on the fuel sending unit. Black fuel line is supply fuel.Blue fuel line is return fuel. The electric plug supplies power to the fuel pump and fuel sending unit to operate the readout of the float.


Here is a thread that shows how to remove the sending unit.
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