C270 Saddle tank balance issues

[nel5on]

Maybe you can suggest something....
The C Class mercs W203 2000-2007 have a saddle tank due to the driveshaft, and a pump from the left to the right(no pump to the motor, it has a mech pump for lift to the engine), with the pick up on the right, and sensors to balance the tank. These fail, in many different ways, leaving your car half full on one side and empty on the other...but still on the side of the road.
(to fix this with new parts via Merc cost 500-600, and car value is lowish anyway)

It is a plastic tank, so I am considering to slimplify things by drilling both sides on the low points and running a "balance" pipe. It has to clear a drive shaft, but a anti roll bar is below the driveshaft, so I suggest I route it along that to the other side.....I'm thinking the size of the pipe will limit the fuel slosh from one side to the other.

I cant see why this cannot be done.....or am I missing something. I can use fuel pipe, correct fitting(not sure what they are) and thinking will shield the fuel line across the sway bay inside conduit.

If this seems correct, can you suggest a correct plastic fitting or another option?

Thanks in advance,
Nelson

[colnerov]

Hi, personally I would either put another pick up in the left side from the top of the tank and either 'T' it into the other one or have a change over to pick up from either side. Alternatively replace the sensors with a manual switch to control the transfer pump or have it running all the time to keep the right side filled up and the excess going over the hump until the level drops to keep the right side with petrol for the pick up.

Colin

[bmw2101]

i think you would need quite a big bore pipe to do it manually?

i take it the pump takes from one side returns it to the other ?

[v8ian]

I don't think a pipe any bigger than the feed pipe to the engine is needed as its only a balance pipe,

[bmw2101]

jyust thinking about that again, it must have feed and return in one side, can you put a pipe from the full side pick up and T it into the return of the other side, i think it would venturee effect and pull fuel over?