928autobahndreamer

Finally getting around to replacing the fuel lines. I managed to replace the infamous U line without much difficulty. Honestly that hose was pretty tough. I don't think it was due for failure anytime soon.

However, the the fuel line that comes off the fuel pressure regulator seems to have a tight U bend that seems even more worrysome. I know that Roger was very concerned about taking a high pressure hose and bending it more than a certain amount. When I take the fuel line that he supplies and try to match the routing of the origonal it seems to pinch the line a little. This has me questioning if I am looking at the right area. So I have included a picture.

I am looking at the line coming off the back of the fuel pressure regulator to the left of the U-line (already replaced). Maybe Rog can chime in here and straighten me out.

Thanks
Steve

Rob Edwards

That line is unique to the '87 S4. However, the rubber portion of the feed line near the jump post also has a tight radius to it, for that I had to make an extra long loop of fuel line there (2-3 extra cm) so it wouldn't kink. I suspect you need to do the same thing at the rear FPR. Hopefully there's enough room between the MAF and above the throttle cable for extra looping.

NickT

Maybe see if you can get the hard line that goes there on the '88. 928 Inlt should be able to hook you up.

Mrmerlin

to use the hard line you need to replace the FPR to accept the newer style fitting, if you add a bit of line to the hose it will be OK try test fitting it to see how much you need , make sure the throttle cable doesnt rub on the line when you get things back together

Rob Edwards

just for posterior-ity sake, here's the configuration on a '90. You can see Rog's new clamps on the rubber segment of the fuel return hose at the back of the metal 'U' and at the connection on the fuel cooler:

ROG100

Steve,
Sorry been busy and just catching up on my Renn reading.
The 87 is special in this area, and as Merlin has said already, make a bigger bend to the hose. Just double check that you are not rubbing against anything else.
Roger

928autobahndreamer

Thanks everyone for the replys. I love this site. Fuel lines should be done tonight.

928autobahndreamer

Well, the fuel lines didn't get "done" until tonight. Just haven't had the time to do any wrenching. I still have some concerns about the fuel line mentioned earlier. I added quite a bit of extra to the loop and the line still wants to flatten some. I am not sure how much this is going to impact fuel flow. I tried to get a picture but it doesn't show really well. Do I need to be concerned about this?

I also am very glad I changed out this line. It was incredibly brittle. I practically came apart in my hand. Just after I took this picture I was able to tear the line in half just by twisting slightly. This could have been very bad.

the flyin' scotsman

Wow............glad you caught that in time.

The '88 + is modified for a reason...........it may be easier to upgrade and have less of an issue. I replaced this line with no concern.....YMMV

928autobahndreamer

Thanks Malcolm, it looks like I have another thing to add to my to do list. Man, I am starting to fix things and the list is getting longer instead of shorter.

ROG100

I do not like the look of that hose.
I have another hose I have been considering adding to the kit for the 87 cars.
Let me send you one to try out. I think it will solve the problem.
Best,
Roger

928autobahndreamer

Thanks Roger. I tell you what, I really appreciate how willing you are to help. It is vendors like you and a community like rennlist that makes it possible for me to own my dream car. Again, thanks for all the time and effort you put into making sure these cars stay on the road.

Who knows, a few more miles on that fuel line and I don't think my fire extinguisher would have been enough.

Steve