Meatful

Are there supposed to be washers on either side of the fuel hard line? See picture below showing possible crush washer points A and B where I slid on copper washers to illustrate.
And what is the torque spec for the end nut (not shown in picture)?

Thank you!

1986.5 928S AT

Speedtoys

http://www.autoatlanta.com/porsche-p...section=201-05

https://members.rennlist.com/pirtle/s4torque.htm Suggests 8FtLbs??6.5.0

Meatful

Thank you Speedtoys. Even with the washers and the cap nut torqued down I have a steady flow of gasoline coming out of the junction. When I got the car it did not have washers at points A and B. Really confounded, so I ordered a new fuel (hard)line, cap nut, and washers today to play it safe.

ammonman

Likely that whoever put it together without the copper gaskets tightened the cap nut so hard they deformed the banjo fitting on the hard line resulting in the leakage you have. BTW, you can re-used the copper gaskets if you anneal them first.

Meatful

Great point Ammonman, also since found a pinhole in the hardline in a different spot, so multiple failure points. I guess the previous owner couldn't smell.

slownrusty

Porsche recommend only 14-ft.lbs of torque for that 19mm cap nut, so take it easy and don't overtighten it against the new copper crush washers.

dr bob

Once the steel nut was tightened onto the steel banjo with no washer, you were doomed to a life of leaks. Get the new S-pipe and new nuts, in addition to adding new washers. I've polished sealing faces on otherwise unavailable banjo fittings and nuts where they have been galled from wrench abuse, and it's no fun and the risk of failure is high. Fortunately the S-pipes for the 928 are still available (as of this writing anyway) so no need for the recovery steps. Look forward to a time when we'll be fabricating custom fittings and hose sections for more and more of these pieces; it's just a matter of time. Kind of tempting to stock a couple spares of the S-pipe for the inevitable time when they fall off production schedules.

I've gotten in the habit of smearing the washers and the threads with a little Teflon thread sealing paste before assembly. Then reduce the tightening torque by 10-20%. It acts a lot like anti-seize but is fuel-proof, which common anti-seize compounds are not.

Over-torquing the nut risks stretching and bending the hollow banjo bolt, will gall a dry sealing washer, and will work-harden the washers even more than usual. You pretty much get one shot at tightening onto dry (unlubricated) washers, and they must be soft with perfectly parallel smooth faces when you start if you expect them to seal. Further, the banjo must line up perfectly; you can't expect the nut to un-twist a distorted S-pipe solely by squeezing on the shoulders of the banjo fitting itself. Plan on counter-holding the banjo on the new S-pipe as you tighten the nut, in parallel with holding the check valve on the pump itself, so there's less chance of distorting the pipe. Same applies to disassembly next time, even with the threads and washers lubricated by the Teflon paste. Similar guidance applies to all the other banjo fittings and seals on the car, including the fuel filter and the power steering connections, plus the sealing cap on the fuel rails and the metal-to-metal fuel connections at the fuel rails.

husker boxster

What is a proper amt of time with a benzine torch to anneal an old washer?

Gage

Apply heat until copper is dull red (do this in low light to be able to see the color), quench immediately in cold water.

Speedtoys

Heat it with the tip of the blue flame until it turns black.
KEEP GOING until it turns glows bright red (black is not bad, its part of the trip)
Drop in water.
Done.