DIY: R&R Fuel Tank Sending Unit (p/n 1295421117) with Photos

[aam]

Mine was reading like two gallons less.
Then last week, I filled it to the top.
You got it works, nothing is wrong.
I never had to fill it up all the way, if the pump clicks to me, that it is enough.
Now I know better.
Not that I really care. Lol.

Regards,
aam.

[lynns]

Originally Posted by Griffin48

Suggestion: Right angle needle nose pliers could be used if necessary in place of the inverted "u" bolt to remove the tank unit.

I found the following Crescent Double-X Bent Long Nose Pliers - Tools - Hand Tools - Pliers & Sets at Sears for $19.95 and they worked great.

[lynns]

My new, five month old, sending unit has been reading 7/8 th's of a tank when the tank is full so I pulled the sending unit and sprayed the electrical contacts with CRC- MAF electrical contact cleaner, let it dry, and reinstalled the unit and it now reads completely full.

Let's see how long this lasts.

[anaesthesia]

Hmm, I've had some speculations regarding the function of my fuel meter and refueling. It appears as if some gas pumps can't manage to fill the tank to full, regardless if you top off. Some do fill pretty well in my case, I don't know why... I blame the gas stations! To me it depends on the pump more or less!

While we're on it, how far do you dare to drive in the yellow section? =) Everytime I decide to fill up, it only fuels up to around 67-68 liters. According to the manual, there should be 12-13 liters left! Maybe my fuel tank sending unit needs cleaning after all!

Regards,
Robin

[lynns]

Mercedes fuel tank level sensor sender tool @ $29.99 w/ S&H | eBay

[RKH]

My experience is : if I drive for a while and pull into gas station to fill it up, it will 'click' off early and the fuel gauge will not show full. But if I go to lunch first and then fill it up, gauge will show full. So may have to do with pressure in the tank ?
Anyway, long as I don't run out of gas it doesn't really bother me. When the empty light comes on, I can go another 40 miles with what's left.

[lynns]

Originally Posted by RKH

Anyway, long as I don't run out of gas it doesn't really bother me. When the empty light comes on, I can go another 40 miles with what's left.

With the car it's an anal thing for me. But, if I had a bad fuel gauge while flying it could be more than a real problem.

[sd_cowboy]

Originally Posted by Griffin48

Thank you for a quality description of the task. It was very well put together.
Regards,
Griffin

I want to thank you too for this great thread! I just finished removing & cleaning my tank sensor as it wouldn't get much past 3/4 even when I knew the tank was full. The carpet in my storage boot was very well glued down so I ended up cutting a hole in it & will put in a patch once I know this sender is fixed.

I used a 2" wide "U bolt tool" as described and finally used the bench grinder my wife bought me years ago to grind the ends down to fit the socket holes. The sender turned easily & out it came for cleaning.

BTW, Autohaus lists a fuel tank sender seal part no. 1079971345 which is too small and does NOT fit so anybody else doing this R&R should save their $0.99.
mark

[board57796]

Glad it helped! Easy job, huh?

[sd_cowboy]

Originally Posted by board57796

Glad it helped! Easy job, huh?

Yes it was a very easy job thanks to your thread. Unfortunately, it didn't fix the sender so it looks like a new one for me.