Fuel Return Line

teahead

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I hope to do this one day, but maybe take the fuel source line, and get some straight pipe and have it parallel the bends???
 

JMinPDX

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Lucky for me 1974 e9’s and e3's had a return line for emissions control purposes. The 74 tank also has a built in spout for the return line. It made installing fuel injection easier.

As I recall the return line runs parallel with the fuel line. Looks like the return line for a 74 e3 may still be available, item #2:

http://www.realoem.com/bmw/enUS/showparts?id=6213-USA-05-1974-E3-BMW-30SBav&diagId=16_0405

You may be able to incorporate the factory line.

The 74 e3 tank will not fit earlier cars.

Good Luck

John
 
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e30strube

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My fuel line has been off the car for a couple years now, so I don't know the factory routing. Does anyone have an undercar pic by chance? Does the line just run on the outer edge of the car, then return back towards the tank just in front of the rear wheel?
 

duct-tape

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I'm commenting but I'm not 100% sure and I should go out and look, but I think it runs in the tunnel, along the driveshaft
 

JMinPDX

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My fuel line has been off the car for a couple years now, so I don't know the factory routing. Does anyone have an undercar pic by chance? Does the line just run on the outer edge of the car, then return back towards the tank just in front of the rear wheel?

Yes the fuel lines run along the drivers side edge just inside the rocker edge.
Then they make a left before the rear axle following the contour of the underbody above the axle more or less. The lines enter the trunk, the return line above the spare tire and the fuel line in the corner near the gas tank. That’s how they’re run on a 74 e3.

Here are pics I’ve found of a 74 e3:
From the engine:
E823D921-C9BA-41AE-964B-6DBEC4EE308B.jpeg


Then inside the trunk:
722F7913-1D8B-4BE1-BC32-FE33BA4F4919.jpeg
 

e30strube

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I ordered the return line from BMW yesterday. There are 5 available in Europe for ~$30, so it's cheap. There were no dimensions of the pipe, so I would assume it comes pre-bent. I will update the thread once I get it for future reference.
 

teahead

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I'm kind of confused.

I would think 16 12 1 111 538 (#1 in the diagram) would be part of the supply line since it's hooked up to the fuel pump???

I would think #10 would be the return fuel line.

fuel.jpg
 

e30strube

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I ordered 16121111535 , which was linked in JMinNJ's post. The dealer said there were 5 available in Germany at ~$27. Teahead, it looks like you referenced the Coupe part, which looks to be a different part. I believe the routing of the line is also different under the car.
 
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