GerritD

Can someone tell me which of the 2 flex fuel lines is the supply fuel line ?
I had replaced my fuel lines but I am not sure if I put them back correctly since my car won't start......perhaps I switched the supply and return fuel line

Here's a photo :



thanks for your help

Gerrit

btw : my 928 is a 1980 Euro model

jwillman

On my U.S. 79 the fittings are different sizes so it should not be possible to cross the two when reconnecting.

GerritD

I know but the problem is that I replaced the line (but I kept the original bolts since it's a NLA item) from rear to front of the car. So it has been disconnected completely.
I noticed that these lines are crossing on my '80 928...and my supply line is the upper line you can see on this drawing. So my supply line that enters the connection at engine is a male connection.
But is it the correct one... ??

jwillman

I did my fuel lines recently and the hose sizes (inside diameters) in the engine bay of my U.S. 79 are different sizes as well. Did you do the lines one at a time? unless you mixed fittings the hoses should be correct. As the hoses are different demensions seems you would have had a hard time inserting the larger fitting into the smaller demension hose.

GerritD

Jim,

I did the lines at the same time (which I shouldn't have :-) because I replaced them by PTFE racing fuel hoses.
In fact I had problems getting the 2 new flex rubber hoses (the 2 hoses that connect the hard lines coming from under the car to the hard ones at the engine).These 10inch hoses are NLA at Porsche. 1 hose has 2 male connections, and the other one has 2 female connections. But the inside/outside diameters are the same.
Can you tell me if the hose with the 2 male connections , is connected to the fuel supply line ? According to the image it should be the one on top

jwillman

just went outside and traced my lines from the connections on the fuel distributor back to the flex lines. On my car the bottom flex line is the pressure line to the distributor.

GerritD

thanks for verifying, Jim ! You're really a great help because indeed I had to switch the 2 lines on my car to have exactly the same configuration as yours.
I verified this by letting the return line not connect and check whether fuel came out of the return line at engine side when trying to start. And supprisingly no fuel came out, so this means this is not the return line but the fuel supply.
So I switched the return and fuel line connections and now it works.
But my car still did not start...perhaps it is an ignition issue.

However I did not touch the ignition or motor parts for about 5 months.
..
and my search continues

jwillman

gerrit,

Good luck. My US 79 is also a project car thatw as a non-runner when I started. Keep posting what you have done and symptoms and the experienced folks here can surely help.

GerritD

Thanks Jim,

my '80 928 did run when I bought. only a lot of electrical issues due to cut wires and wrong wiring behind dash pod. I finally managed to identify and fix everything. A took me about 1 month to complete.
I will repaint my 928 in its original Grandprix White color.
btw your car looks superb...can you send/post me some more photos ? I'm just curious...

kr

Gerrit

ROG100

The hoses are very easy to replace.
You need 5/16" and 3/8" EFI hose and clamps for about $25.
They can be replaced in situ as well.
No need to use racing PTFE hoses as they are very over specified. I also do not know how the PTFE will stand up to ethanol either.

jwillman

Gerrit,

That's the great thing about a 20' photo! Sadly she is much rougher close up. Interior needs work. The exterior is a poor respray and I have paint bubbling and peeling on the drivers rear fender and rust around the hatch trim.

But she is a work in progress and 2 weeks ago she made it around the block under her own power

I have had a great time (most of the time) bringing her back from the edge and the folks on this site have been instrumental.