205 Petrol - Fuel Return Pipe.

alanshep · Unread post by **alanshep** » 04 Dec 2006, 19:05

Hello.

I'm in the process of changing the engine on a 205 1.1 (TU Engine).

The Haynes book mentions disconnecting the fuel return pipe but there isn't one on the original engine or even on the car as far as I can tell. The original engine used an in line fuel filter with the output of the fuel pump direct to the carb.

The replacement engine has a filter fitted next to the carb with provision for a fuel return pipe - but there is no pipe to connect to it!

I have 2 questions:-

Firstly, should there always be a fuel reurn pipe fitted to the 205 ?

Secondly, in the apparent absence of a fuel return pipe is it OK to use an in line filter and then connect the fuel pump output direct to the carb - as per the setup with the original engine? (I suppose the carb needle valve has to withstand the fuel pump pressure in this arrangement).

Thanks

Alan

Unread post by **CitroJim** » 04 Dec 2006, 21:03

Hi Alan,

The only 205s to have return lines to my knowledge were Injection models and Diesels. Carb equipped models never did IIRC

Provided you are using a mechanical fuel pump, you should be fine with the set-up you are proposing to use.

AndersDK · Unread post by **AndersDK** » 05 Dec 2006, 00:44

Standard car mechanical fuel pumps dont deliver more than approx 0.25bar fuel pressure. Easy for the float needle valve to withstand.

You will find that the return fuel stud on the carb is directly connected to the fuel inlet stud on the carb. Only a small fine gauze mesh filter is found between the 2 pipe ports.
It would be perfectly allright to blank off the return fuel stud in case you only have a feed line.
Opposite : if you have a single stud carb and both a fuel feed and return line, its common practice to use a T-piece close to the carb to connect everything up.

Any inline filter is commonly fitted as close to the carb as possible. But may also be found prior to the pump to protect this.