W202 fuel tank question

[danny allen]

Just bought a w202 c180 and the guy I bought it off said there is some kind of problem with the fuel tank.

he claimed that the can "ran out of fuel" if it went under half full on the gauge

he seemed to think the car had 2 fuel tanks is this the case?


cheers


danny

 

[vijilants]

The fuel tank is a "saddlebag type".

There are two fuel level sensors, one on each side. These control the levels between both sides.

You have a faulty sensor or the interconnect pipe between the two is blocked.

If you are replacing the sensors, replace both.

 

[vijilants]

Sorry, I was in a bit of a rush earlier so did not manage to complete my post so here goes:

The two fuel level sensors keep both sides of the tank level plus also send the reading back to the fuel guage on the dash. What has happened in your case is one side of the tank is empty and the other side still has fuel, but the fuel is not flowing from one side to the other.

The sensors are in excess of £200 for the pair if I remember rightly if you go to MB. Euros also sell these but I don't know how good they are and personally I'd stick with the original part.

Also when you remove the sensors, ensure that the pipe that connects the two sides of the tank are also blown clear with compressed air.

 

[danny allen]

how do i get to the sensors and the pipe that connects the tank?

thanks in advance

danny

 

[spock500]

I pulled mine apart during a veg oil conversion although this was for a diesel.

The saddle tank system on the diesel doesn't use sensors although it does have two sender units to keep the correct fuel level reading.

I think the CDi's also have an intank lift pump but not sure about the petrol variants - there maybe a tank strainer that's blocked, take a look here for my adventure

vegetableoildiesel.co.uk - C250D Saddle tanks - Powered by XMB

 

[danny allen]

would i be correct in thinking that each tank has a seperate drain then?

 

[spock500]

Yup, the two senders are held in by alloy rings - MB do a special tool to remove them but you can tap them round with a small punch.

Once they are finger loose rotate until fuel starts to drip then get the bucket ready - the other way is to pressurise the tanks which MB recommend then use a special hole to screw in drain pipe.

 

[danny allen]

could i not blow an airline back through the fule line to clear it?

 

[vijilants]

could i not blow an airline back through the fule line to clear it?

Nope,

The pope connects both sides of the tank together.

 

[vijilants]

Nope,

The pope connects both sides of the tank together.

Sorry....that should have read pipe .

It is not connected to the fuel feed lines.

 

[danny allen]

funnily enough it seems to have cured itself

I thought I'd let it go below half a tank to see what happened and touch wood there hasn't been a problem yet

 

[Smartchoice]

I have this problem please can I get pictorial instructions on what to do?

 

[mr. shr]

Yup, the two senders are held in by alloy rings - MB do a special tool to remove them but you can tap them round with a small punch.

Once they are finger loose rotate until fuel starts to drip then get the bucket ready - the other way is to pressurise the tanks which MB recommend then use a special hole to screw in drain pipe.

I know this is an old thread but today I discovered that one of my senders is leaking.
I've found that the metal centre bit bit of the sender is slowly dripping. Is this the alloy ring that you refer to above?
How do I remove this bit please?

 

[spock500]

I know this is an old thread but today I discovered that one of my senders is leaking.
I've found that the metal centre bit bit of the sender is slowly dripping. Is this the alloy ring that you refer to above?
How do I remove this bit please?

Hello bud, The centre part is the sender itself which is held in place by a ring. If you look up it has four notches similar to a watch back which a special tool locates into. It's similoar to the top left in the attached pdf below. http://www.baumtools.com/uploads/files/Fuel Sender Tools.pdf Mine came out by tapping gently with a small punch.

 

[mr. shr]

Hi, thanks for replying.
I think we're talking about a slightly different thing. The bit where the leak is coming from is the small metal disc thingie in the middle of the sender.

From what I understand, the ring you're referring to holds the whole sender unit. But the bit I'm talking about is right in the middle of the bigger outer ring.

I was under the impression that the small metal ring thingie that I'm talking about could be removed and resealed without taking the whole sender out.
Is this not the case?

(I've started another thread on this that shows a pic of what I'm trying to describe).