cewyattjr

On my E300D, there is a banjo bolt return line that brings fuel back to the fuel filter. I recently replaced this line with a new one, which, for whatever reason didn't include an o-ring. I noticed when I pulled the old one there was an o-ring, so I had to reuse it.

Anyway, when the car sits for only a few hours, I see this line (#7 below) clear (no fuel), so I'm assuming air is getting in.

So just a basic question -- is it important that the little hole in the bolt line up with the fuel line itself? I'm assuming so. I can look into tightening it up, but I am concerned I would lose the alignment if that's needed.

The new connectors are otherwise nice and tight, so am curious how I'd get air in there. I'm considering changing my fuel filter, 'cause that's easy, though I don't think that's a candidate for air intrusion.

Thanks!

Chuck

Lancelot

Could be another o-ring, could be air getting in at a totally different spot. Does the engine start up without a single misfire when you crank it after preglow?

cewyattjr

Hi Lance!

Yes, it turns over fine. That one was the only o-ring I didn't change out. I guess what I don't quite understand about the whole banjo bolt thing: I actually see the little hole in the main bolt, so I am wondering if it needs to somehow line up with the fuel line that comes off of the ring that goes around the bolt. Or maybe it doesn't matter?

To work with this particular line I have to remove the manifold so unfortunately "playing and testing" is kind of a labor intensive thing!

Thanks,

Chuck

Lancelot

If it turns over fine there's no air in the primary pressure system, so if you don't have any Diesel leaks I wouldn't worry too much about it. I believe the hole in the banjo-bolt doesn't need to be aligned. There some space inside the ring that goes around it to match the diameter of the hole in the bolt.