Porsche Repair: 944 Fuel Line Repair, fuel hoses, accurate gauge

Question
Dave,

I've been doing a pretty good job of keeping my '84 944 running regularly, but I'm getting some dry rot in my fuel feed and return lines in the engine compartment.

These are one piece lines, hose/ferrule/metal connections, all the way back to the rear of the car. No connections except to the fuel rail.

There has got to be a better way to repair the leaks with the lines in the engine compartment than to replace the whole fuel feed/return system. Besides this is costly and I can't find OEM replacements anyway.

thanks,

Phil

Answer
Hi Phil,

I too was unable to find any listing for OEM fuel lines in my source that's a pretty accurate gauge of "if its not listed here you can't get it".  

It's very hard to tell, but your rotten flexible fuel lines do eventually connect to hard metal lines leading back to the fuel tank.  There's no way the manufacturer would run those "soft" fuel lines under the car where they could be damaged!

I'd suggest finding those connections.   If you really can't see them from above they are probably lying flat on the firewall...so when you are on your back under the car all you see is inconspicuous and unmarked metal lines coming from the firewall area leading toward the back of the car.

You'd be better served to replace those two flexible lines in their entirety...and be done with it.  Get some very high quality fuel hose.  (I tried to get you some good  recommendations for fuel hose...what I found was "....the best is usually labelled with the word "fluroelastomer"...which is in my Haynes 944 repair manual.  I've never heard of this and the internet does seem to want to give up any good info on it this morning.  I use the best my local auto parts store has, although I've heard other foilks say that Earl's fuel hoses are best.)

Certainly, at this point you're going to want to do this job once and never mess with those lines again.

My own personal approach would be even more elaborate. I would find a way to extend the metal lines from under the car as far forward and as close to the fuel rail connection as possible (using brass compression fittings, tightened within a few degrees of their limit.  My new lines would be securely fastened to the car's frame or similar, so absolutely no vibration is transmitted to them.

Finally, and this is the key...I'd buy the best fuel line I could find, in the shortest length possible, so that the "flexible" part, the most vulnerable part, is completely visible every time I look into the engine compartment.  

There you have it.  If you have any questions, please write back using the follow-up feature of All-experts.

Thanks

Dave