Please help me fuel gauge says 1/2 a tank and runs out of diesel

pabsh32

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Please help! I have a 1996 S202 C 250 td estate, and fuel gauge is saying 1/2 a tank of diesel, but over the weekend I have had to have recovery out to start it because it ran out of diesel and i know I need to replace the sender units but having limited fund i can only do one at a time which one am I best doing first, plus the recovery guy suggested installing a manual primer and a non return valve to make starting it easier any help or tips would be greatly appreciated.
 

alexanderfoti

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I would run it down to half and actually look in the tank via the sender hole and see if its half empty.

You can try and run some diesel injector cleaner through it which can help with dodgy tank senders.
 
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pabsh32

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The big problem is the sender units are on the bottom of the tanks worried about getting covered in 1/2 of diesel, is this a common problem with this model
 
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pabsh32

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I will try the diesel injector cleaner and see if that helps
 

alexanderfoti

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I wasn't sure if the 202 had saddle tanks. That is a good shout though, the common causes on 203's running out at 1/4 tank is the return flow from the common rail pump being too low. Not sure if the 250 TD has the same scavenging going on.
 
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pabsh32

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That was a great help thank yoy
 

LostKiwi

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I wasn't sure if the 202 had saddle tanks.
Definitely does:
B47015000083.000229.png
 
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pabsh32

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So if I am understanding it correctly its the right side where you fill up that empties and the left side stays full so if I replace the right side one first this would sort out the fuel problem
 

om613

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Quite rare that these saddle tanks play up on diesel.

Common issue with veg oil users - the higher fuel density affects the venturi link balancing them.
One tank empties whilst the gauge shows OK.
 

Dogfish

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I had "saddle tank syndrome".
V annoying!
Lived with it for ages then it let me down big time and had to be towed to Mercs who fixed it for a fairly reasonable cost.

New Sender not calibrated very well and runs dry at just under 1/8 left tank so I just keep a note of mileage and fill up with diesel as and when needed.
 


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