Fuel pipes - which way round?

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maf260
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Post Thu Jun 16, 2011 9:41 pm

Next question - I'm about to connect up the fuel lines to my M52 conversion. I know that some have fitted them the wrong way round (flow & return) - what is the correct way please? On the chassis rail one sits higher than the other and on the fuel rail it's the same. Is it a simple case of top one to top one, or do they fit the other way round?
E30BeemerLad
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Post Thu Jun 16, 2011 9:48 pm

On the fuel rail (assuming you are using the M52 fuel rail) the rail with the pressure regulator is the return line.

I can't remember which one is which under the car. Whichever one goes to the passenger side front of the fuel tank is the return, so follow it from the tank to the front of the car.

Or if you have the wiring done, flick the ignition on and see which one showers the engine bay with fuel :D
maf260
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Post Thu Jun 16, 2011 9:53 pm

The engine has a M50 inlet manifold - would the fuel rail be different to M52? Wiring's not done yet, so can't have fun with the fuel pump! Trying to avoid all of the obvious mistakes before I make them if possible!
E30BeemerLad
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Location: Norfolk

Post Thu Jun 16, 2011 9:56 pm

If you are using the M50 inlet manifold with the M50 fuel rail, that looks more like a box section, then the feed is to the front of the rail.