Fuel Line Disassembly

Found a fatal kink in the single section of fuel line running from the "quick-release" coupling.

Can someone provide detailed instructions on how to separate this coupling please - I've done the usual searches and am none the wiser.

What sort of pressures do the fuel lines run at - I'm concerned garden variety reinforced fuel hose may stretch with detrimental effects on injection performance / pattern.

Worm drive clamps over rubber fuel hose on the existing barbed fittings looks like a leak waiting to happen ...

Any common or garden efi fuel hose will be fine, the pressures aren't absurd.

If the 'Quick Release' (Snigger!) refuses to do so easily after de-pressurisation, (Disconnect the pump's electrical connection and spin the motor on the starter to relieve it.) then I just whip off the tank and injector lines in one piece, throw the tank on its back like a stranded turtle and then have a go at the stupid QD fitting in a place where I won't risk busting the elbow!

Lubricating the female part of the fitting with Vaseline or rubber grease will help for future removals.

Note if you *Do* bust the elbow they are available as a separate part, just not for Guzzis!

Pete

Pete Roper wrote:

 ...... If the 'Quick Release' (Snigger!) refuses to do so easily ......

Pete

Yeeess Pete - said Quick Release coupling is most definitely worth SEVERAL teeth grindingly "Oh How We Laughed" sniggers - what a perverse cunnuva contraption it actually is !

The tank and injector lines (with injectors still attached) is lying in Missionary Position 1A on my sacrificial slab following the installation of one Wilbers rear shock and a major reseal job on the connecting pipes and drains from the airbox. Those drain lines are a potential source of raw, unfiltered air entering the engine if the tube is damaged along its length or poorly plugged / sealed. I've treated these drain tubes as "visi-gauges or sight tubes" that are normally sealed at the accessible end but can be opened, drained of any water or fuel and resealed.

The single fuel line is damaged and condemned to the bin. Since the fuel line is finished, I was just gunna de-pressurize the line at the fucked pipe with a scriber and then massage the coupling. I see the grey "sheath" part of the coupling has flats on it. Do I squeeze / compress the coupling lengthwise to reverse the normal sealing effect of pressure in the lines and then turn the sheath .... or should I just go for the sharp steel blade, cut the sheath and remove the nuisance coupling permanently then reconnect new fuel line directly to the 90deg tank fitting ?

Every bike / machine has its own service intricacies - this poorly performing "quick release " coupling is just part of the art ..... but a seriously fucking annoying part

Agreed. Gave me no end grief. Blade runner fixed it the first time refitted with a standard hose clamp.

Until Oz1200 posted.
1) "Disconnect wires to fuel pump"
2) "Ignition on and crank engine"
3) "Push me - pull you" on the quick connect.

Don't know why the dumb arsed local Guzzi mechanics couldn't tell me that, maybe they wanted to sell me a new fuel pump when I broke it. ?????

The bike is powered down at the moment with battery and tank with lines removed so the plan is to de-pressurise the line with a sharp stabbing implement ("take that ya bastard - and I fucking meant it too") and then massage the coupling. It's the disassembly method with the coupling that's the issue now

Just like an air line fitting. Push the line and coupling towards the red plastic spigot and then pull the collar towards the pipe. You should then be able to withdraw the coupling from the spigot.

pete

If you are going to replace it with new hose and clamps, just cut the bastard in half.
I cut mine longitudinally near the QR mechanism and then sliced round once I was past the male barb.
This only shortened my fuel hose by about 20mm.

Then refitted with standard hose clamp, I now have the option to remove with a screw driver if I'm not able to pump the line empty.

Well as in many failed endeavours that require the patience of a saint and an extra set of hands in addition to my existing 9 and 2/3 fingers, the NON QD coupling has ultimately surrendered under the tender mercies of sharp steel (opened with the sharpened end of a small screwdriver).

I cut the external sheath away and then cut out the 4 grey plastic locking lugs that grasp the flange on the red 90deg elbow. This allowed the barbed external section to slide off the internal red elbow.

I don't want to fuck with the primary elbow fitting - there's a serious dose of mission creep lurking around this connection and its equally troublesome internal mates.

Sooo the current plan is to use boiling water to heat a high spec plastic hose (Esdan Airbrake SAE J844 Type B 3/8" - fuel suitable) and force this heated hose over the barb at the 3 way junction to the injectors and the barb on the external section of the original elbow assembly. I will seal the external section onto the prime internal bend with additional O rings along the 9.5mm long "collar" space now left by the removal of the main locking lug part that was cut away for disassembly.

I've got a fuel-proof (but sadly not fool proof) fiberglass resin that will be run into the rear of the assembled inner and outer original parts of the elbow assembly to provide additional sealing plus lock the sections together.

Routing of the new fuel line has its own issues. The line of best fit for the injector "branches" seems to be across the top of the front of the airbox with the 3 way connector positioned at the right of the airbox for maximum interference with the rest of the rats nest of pipes / cables etc

It looks like the 90deg tank elbow needs to be angled at approx 30deg left of the bike / tank centreline for the fuel line to clear the alternator. The current plan is for the fuel line to run forward from the elbow on an angle to avoid the alternator then bend in a vertical curve back to the 3 way connector at the right of the airbox. I'm going to also chase up some heat shielding for the new plastic fuel line or maybe just go for stainless braided hose from the outset. The stainless braided hose has the problem of bend resistance and additional weight (compared to plastic tube) that will be transferred to the low spec, plastic tank elbow.

None of this is cast in stone yet. The plastic tube might be more trouble than it's worth so it depends on what sizing I can source in stainless braided hose. Brain surgery it may not be, but in the confined cluttered spaces that are available to run "services" through on the GRiSO, any shift or change has CONSEQUENCES.

So the end result of my plastic fuel line fuckup has been the purchase of a length of 5/16" ID Gates fuel injection hose, about 8 small O rings and 2 lengths of woven fiberglass tubing for heat insulation.

I kept the original tank elbow minus the grey QD parts. I fitted as many O rings as possible into the external socket section and then squeezed the O ring equipped socket over the inner male shank. This provided a reasonably well sealed join between the 2 sections. Next step was to use a fuel impervious vinyl ester fiberglass resin to encase and fix the entire assembly together. I simply ran some duct tape around the assembled parts and poured the liquid resin into the duct tape "mold" - sealed perfectly and permanently.

The best fit for the new fuel hose ran forward from the resealed elbow, fits well resting on the alternator in the space between alternator and fuel tank then back to the injector branching at the right of the airbox.

The new fuel line is protected from high temperature and abrasion by 2 layers of fiberglass tubing. Autobarn wanted a ridiculous price and a pipe specialist Pirtec wanted $70 for 700mm of heat protection tubing - fuck you very much I said under my breath and went to an large electric motor rewind workshop and bought 2 lengths of approx 700mm of high temp resistant fiberglass tubing of increasing size so one fitted inside the other for the princely sum of $6 each.

The job is done at a low cost, plenty of safety / strength redundancy - no leaks or issues.

Hi Lenz, a bit late to say now, but the length of said hose is not critical, it only supplies fuel under pressure to the injectors. I did this same mod 12 months ago and made the hose a lot longer. Now when removing the tank I can pick it up and turn it sideways to reach the disconnect easily.

The best fit that I could sort out to route the new pipe had the length at ~ 700mm which is significantly longer than the original plastic line. The new pipe is slightly bigger in the ID also. Overall a simple hose line with 2 worm drive clamps is a hell of a lot more functional than a short, kink-prone, temperature vulnerable plastic hose hooked up to a "quick detach" fitting ..... that doesn't detach at all.

Thanks for the info mate

Help! I was removing the tank to get access to the cracked breather hoses.. now I have this issue.

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You'll need to pull the fuel pump to replace the barb. The broken one should now be easier to remove from the female fitting, just be careful not to damage the 'Teeth' in the female fitting.

The barb is available as both a Ford and Aprilia/Piaggio part.

I did one yesterday on my spare tank. The hose was knackered already and the fitting didnt want to come off so I just used some dykes and cut the fitting push pul ring and took a little jewelers type flat screw driver and popped out the 3 little pieces in the fitting and it fell off..that way I didnt have to take a chance on mucking up the red fitting on the tank

On my other tank which I currently use , a few months ago I pulled the original fuel lines then used a exacto razor and cut the plastic hose at each  fitting saving the original barbs then used some nice quality automotive fuel injection hose with good high pressure fuel line clamps and about 6 inches from the red tank barb I installed a metal fuel line quick release fitting in the line that AF1 sells..so in the future I don't have to dick around with and worry about breaking that red fitting on the fuel pump every time I want to pull the tank..........Bob was my uncle.