I don`t think it makes any difference where the bolt is aligned.

I just snug it down, and don`t use a torque wrench. but then I have the filter housing with the #2.

Charlie

The above is correct. The idea behind a banjo bolt is you don't have to line the hole up. The banjo fitting has a channel machined so the fuel/air can flow around it and through the bolt.

jbach, find another mechanic! Please!

Really?

Looking at the banjo bolt I would have never thought that fuel/air would be able to flow around it to the outlet port without first going through the center section of the bolt. There really is enough clearance? Whats the point of drilling the center section and horizontal hole if there exists enough clearance to circumvent that?

I'd like to just take the opportunity to clarify with you the steps of fuel flow in our w123 series.

1. Fuel flows from the primary (clear plastic filter) through the lift pump.
2. Fuel exiting the lift pump flows to the inlet port on the secondary filter housing into the filter itself through the various holes that punched into the outer diameter of the secondary fuel filter.

3. Fuel passes through the membrane into the center section of the secondary filter up through--and I guess around?-- the the banjo bolt.
4. From the banjo bolt, fuel is then delivered directly to the IP.

Do I have these steps correct?

The fuel flows from the lift pump to the top of the filter housing, down through the hole (pic 3), through the filter, up through the banjo bolt, around the banjo fitting and on to the injection pump.

The lower rubber "O" ring prevents the dirty fuel from going to the IP, directing it instead back to the tank. The upper "O" ring prevents any leak from the bolt.

I believe it would be possible to have everything line up, but that would take excessive engineering to be used on a production line.

So, yes, you have the steps correct and a hollow (banjo) bolt is necessary to facilitate the process.

The final answer to the leaking spin-on filter bolt!

I posted this about 5 years ago:

Use a "Nu-Lip" bonded aluminum washer (18Ø). It has a bonded lipped seal on the inside diameter of the washer and seals perfectly even at finger tight. I am still using the original washer I fitted on my car when it was new 26 years ago! They are great for all banjo bolts and available at all specialist hydraulic stores. No need to use a wrench on the bolt when you change the filter.