Author Topic: BE 646  (Read 165579 times)


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Re: BE 646
« Reply #390 on: June 19, 2022, 12:27:56 »
It's a quite long time ago that I posted something. Everything started end of March. I wanted to install the fuel tank and checked the position of the exhaust pipes. Previously, I checked the fuel tank in conjunction with the exhaus pipes --- which leads to a tank modification --- and I installed the fuel tank and checked clearance to the nuts of the rear triangle control arms. Everything was fine. But during the installation of the fuel tank I had to recognise that the fuel tank must be installed first and after that the bolds of the rear triangle control arms must be installed. It doesn't work the other way round  :( .

Second I detected that the exhaust pipes do not hit the fuel tank but the fuel tank straps.

So, to make a long sad story short, I decided to build a new fuel tank with new fuel tank straps. How complicated can this be? I guessed it is a one or two week work  :o . Well, it was a little bit more complex ...
bending the lower part:

welding the studs to fix the fuel tank in the straps:

welding the baffle plates:

and the side plates. It is important to weld the abutting edges from inside before the sides plates are welded to the rear body:

preparing the feed pipe and the inlets for the fuel sender and the outtake:

welding the feed pipe into the body:

preparing the upper plate with enforce braces:

welding all together:

Now, the great pressure check:

I forgot 5 millimeters between the body and the top plate:

and as expected the feed pipe has not perfect although I tried to weld them from inside:

After fixing all these problems the fuel tank holds the pressure over the night and the final water test showed no bubbles.