ML270 diesel leak only when tank is full.

[stumo]

Hi I have just bought a 2002 ML270 CDi. I just picked it up today from the car yard, and I filled it up just round the corner from home (it was pretty much empty every time I saw it and when it was inspected etc - as per usual from a car yard).

Then as I sat there admiring it in the driveway, I noticed the leak, quite bad - enough for maybe 1 litre per hour. So I had a look and it is coming from somewhere above the fuel tank towards the rear of the tank. It has stopped now - after about 6 hours.

Note that I didn't fill it right up, I actually stopped filling because the total price was getting a bit high, rather than the tank, but it just so happens that it was full (on the guage) at that point too.

So I found a forum post about the ML320 having a leak problem when you replace the fuel pump (I guess that is the same as the low pressure pump in the ML270) in the tank, if you don't fit the sealing ring properly. Aparantly the fuel pump was replaced 20,000km ago.

So is this setup the same on the CDI?

How hard is it to lower the tank (once it is pretty empty) and have a look? I don't have a hoist, so it will be a sunny day on the driveway job?

Are there instructions/WIS anywhere, or will I have to bodge one up when I do it myself?

Cheers

 

[stumo]

I have found the answer myself now...

There is a hatch under the 60% rear seat to gain access to the pump. Otherwise it is a major job to drop the tank (diconnecting propshaft, shocks, rear axle carrier, etc etc) definitely not a driveway job. Hopefully it is just the pump seal - I will obviously start from there.

Fuel pump...
http://pointedthree.com/disc/forums/get-attachment.php?attachmentid=4160

Fuel tank...
http://pointedthree.com/disc/forums/get-attachment.php?attachmentid=2689


Cheers.