Fuel line pressure on 97 1100 sport

[Colorobo]

How do you bleed off line pack on the fuel lines to remove tank? Specifically the line coming to the regulator on the right side of tank?

[Weegie]

Are we talking 1100 Sport injection?

When you undo the clips on the lines there will be some spillage, but anytime I've had the tank off on mine (and that's a lot) neither inlet (petcock side) to the system nor return (fuel regulator) needed anything special.

Simply undo the jubilee clamps or whatever else is holding the lines onto the petcock and the regulator then pull them off

Be prepared for fuel to run out the lines but it doesn't spray everywhere if that's what concerns you at least mine never has.

[Colorobo]

11oo sport injection does not have quick connects under tank.

 

[docc]

2 hours ago, Colorobo said:

11oo sport injection does not have quick connects under tank.

 

Seems what Weegie calls a "jubilee clamp", we Yanks call worm-gear clamps, or just "hose clamps."

Pretty fun history on the whole "Jubilee Clip" thing on Wiki.

So, the 1100 Sport-i is set up like the first generation V11 Sport (External fuel pump/ filter/ regulator). Once the system sits for a bit, the pressure just bleeds off. As Weegie says, you can then release one of the [hose clamps] and catch a bit of fuel. I typically take off the return line to the regulator and drain the filter atop the spine frame. Looks to be 100 ml or so, but not pressurized.

 

[Lucky Phil]

16 hours ago, Colorobo said:

How do you bleed off line pack on the fuel lines to remove tank? Specifically the line coming to the regulator on the right side of tank?

Same as a v11 Sport there is no real need to. The only thing that will cause there to be residual pressure in the lines is the internal check valve in the pump at the discharge. I've never seen one that actually holds pressure after it ages. So when the pump shuts down any pressure in the line dissipates through the pump and back to the tank outlet. If the pump check valve is actually working you will get a small amount of spillage when you remove the hose from the regulator but it won't be spraying everywhere. As the fluid is incompressible and tiny release of fuel either from undoing a line or leakage via the leaking check valve will dump the line pressure immediately. It's never an issue in the usual scenario. Some people with the in tank pumps pull the fuel pump fuse and start the engine apparently which runs briefly but I've never had the need to do so. 

Ciao

[Weegie]

7 hours ago, docc said:

Seems what Weegie calls a "jubilee clamp", we Yanks call worm-gear clamps, or just "hose clamps."

Pretty fun history on the whole "Jubilee Clip" thing on Wiki.

 

 

Forgive me docc

"Two Nations divided by a common language"

[Colorobo]

thanks

 

[Tinus89]

On 3/21/2021 at 8:26 AM, Lucky Phil said:

(...)The only thing that will cause there to be residual pressure in the lines is the internal check valve in the pump at the discharge. I've never seen one that actually holds pressure after it ages. (...)

I have, on mine. After changing the fuel filter, wanted to remove the tank again (after priming the setup a bit) for some other work. The fountain of fuel (probably aided by an air pocket in the fuel filter) was quite considerable, and unexpected after sitting for about 60min between priming and tank removal.

[Lucky Phil]

7 hours ago, Tinus89 said:

I have, on mine. After changing the fuel filter, wanted to remove the tank again (after priming the setup a bit) for some other work. The fountain of fuel (probably aided by an air pocket in the fuel filter) was quite considerable, and unexpected after sitting for about 60min between priming and tank removal.

Ok. but was it a a pressure spray of fuel under 45psi or a gush of fuel from the line draining? you always get a stream of fuel when you pull the reg hose and depending on circumstances its either a constant trickle for some times or if its got air behind it a bit more of a flow situation.

Ciao  

[Tinus89]

16 hours ago, Lucky Phil said:

Ok. but was it a a pressure spray of fuel under 45psi or a gush of fuel from the line draining? you always get a stream of fuel when you pull the reg hose and depending on circumstances its either a constant trickle for some times or if its got air behind it a bit more of a flow situation.

Ciao  

The distance covered was over 2.5m, so that would class it as a pressure spray right?

[Colorobo]

So what is the best way to bleed off pressure?

 

[Lucky Phil]

16 minutes ago, Colorobo said:

So what is the best way to bleed off pressure?

 

Well some claim you can pull the pump fuse and start the engine on the residual pressure to bleed it off. Personally I just loosen off the regulator hose with a rag around the joint. Even with 3 bar pressure you get SFA out of it. There's only maybe 100ml in the hose between the pump and the reg and as we know from school science with an uncompressible liquid you only need a miniscule reduction in the volume to dump the pressure.

Ciao  

[Colorobo]

Thanks.