Just took delivery of a new '02 F4. I live 500+ miles from the nearest dealer (purchasing dealer 1800 miles away). Saw the threads on cracked/leaking fuel lines. Looked under my tank at the fule fittings. The white (rearmost) fitting is dry. The black (forward) fitting is sticky/shiny. Very slow leak. The engine cavity under this fitting has collected dark, brown gas varish. How can I tell if the fitting is cracked or just needs new o-ring(s) other than trail and error? I'll replace the O-rings in any case but concerned about the fitting. The lines do not look like they are binding on anything. As an aside, the oil filter did not have a safety strap on it.

Thank you

-- Walter Siegmund (wallycycle@yahoo.com), February 27, 2005

Answers

You might as well get a new set of fuel coupler.The standard ones are a bit brittle,especially the white one.It will crack easily if you disconnect the coupler wrongly or if you handle them rough.It could also start leaking if it's not fitted properly from the factory.This happened on my Brutale.I replaced them with the ducati ones.I have heard that aftermarket fuel couplers are available in stainless steel or billet aluminium and they offer better fuel flow over the standard ones. Regards,

-- Iskandar Z (yojo@tm.net.my), February 27, 2005.

If it was the coupler I would expect to see a larger leek. The 'O' rings are very easily damaged on refiting the coupler so this is where I would look for a slow leek. You should be able to pick some up at any bike shop, get some spares as they are so cheeo you can carry replacements for every time you have the tank off, not that you should need to very often.

-- Mark M (m.magenis@btinternet.com), February 28, 2005.

Ryan-Herco carries the metal ones in the US the 4 fittings will cost about $30-35 as I recall. Colder Products Corp is the manufacturer

Base – fits into tank LCD10004

Insert – fits on hose LCD23006

-- Bill (rgsnumber19-general@yahoo.com), March 01, 2005.

Walter: I'm quite not sure if you have the same problem I had. Mine was not leaking fuel when turned off but as soon as the engine runs, the fuel was spraying a little and like crazy as it got worse(fuel injection). Much like Iskandar pointed out, the coupler is made of plastic and had deteriorated with heat coming from the engine. With the engine running, try to detect if there is actual fuel leaking from any part of the coupler, if not, feel the o-ring between the coupler and the tank itself. Even if it is just the o-ring, it's best if you replace the coupler anyway since it would fail real soon.

-- Jonathan Policarpio (jpolicarpio@hotmail.com), March 01, 2005.

The lines are pressureised by the fuel pump, as soon as you turn the key, so any leek will always get worse with the ignition on.

-- Mark M (m.magenis@btinternet.com), March 03, 2005.