rubber ring / jet assembly pipe to float chamber leak Q.

[Chief]

Hi,
Just went to set idle speeds etc for engine adjustment, but on turning on the ignition petrol started dripping from the end of the jet assembly pipe connected to the float chamber.
We kept tightening the nut but it doesn't seem to have made any difference, the leak persists.
One thing we should ask is, what exactly keeps the jet pipe from coming out of the nut, because you could just give it a tiny (no force required) pull and out it pops.
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Just been shown that there's a small black rubber grommet on the inside of the float chamber, if this wasn't seated correctly would this cause such a leak?
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Lastly, the new jet came with this squashed looking white ring of plastic/rubber, does this serve a purpose, and if not why was it supplied?

Thanks

[MoggyTech]

Sounds like the nylon pipe has come off the Ferrule that fits into the base of the float chamber. Sometimes happens if the jet assy is fitted to the carb before the nylon line is connected to the float chamber. For HS2 carb Haynes manual page 69 shows the order of parts. Either that or if this is a new part, another example of poor quality ?

[Willie]

the idea of the black rubber ring is that it sits around the petrol pipe
and, when you tighten the nut the ring is tightened onto the pipe producing not only a petrol tight union but also clamping the pipe to hold it in position.

[dunketh]

If the metal ferule bit, as mentioned above, has come off the pipe you've had it.
Easiest to buy a new jet, they're only cheap and come with the pipe attached... either that or ask one of the folk around here for one.

I'm sure there are plenty of folk with spares kicking about gathering dust.

[Chief]

This was a new jet. So far it's now all okay, no petrol leaks, so fingers crossed, last time though it wasn't leaking then two weeks later it was, so time will tell, though last time we didn't even know there was the black rubber ring in there, so hopefully that was it.
Only problem was the thread inside the float chamber was damaged, so it's been "re-threaded" by my screwing the jet bolt in (3 days on and my hand still bears pressure marks from the struggle).

[dunketh]

What sort of carb is it? Might be worth asking around for a new float chamber. If I can find my HS2 one you can have it foc, assuming you still have a HS2 carb.

I found with mine I was being too careful with it. Whacking it up super-tight did the job. Nuts to mechanical sympathy!

[Chief]

Hi,
Thanks for the offer, but with any luck it'll hold

[bmcecosse]

You can't really be relying on luck where petrol pipes are concerned - if it can still come out with "tiny (no force required) pull" then that is not good enough - it's going to let you down at best and cause a fire at worst! The pipe must resist a good hard pull with absolutely no leakage - otherwise it's dangerous and must be replaced.

[MoggyTech]

Got to remember what lives just below that float chamber, the exhaust manifold, please take no chances.

[Chief]

I didn't mean it quite like that when I said I hoped for luck, I meant that I hope it stays a good tight fit.
To be perfectly honest i'm a hypochondriac when it comes to cars, the slightest change in noise (new stainless steel exhaust sure has a different noise to the old steel one), the slightest bit of heat haze gets me worrying about things going wrong, so don't worry I have no wish of having a burning vehicle.
I didn't actually dare giving it a good hard pull (I guess it depends what we define as a good hard pull), but a small tug didn't make any difference to it. Also on our test drive we kept stopping and checking every few yards and there were no signs of any leakage. We were taking it to the garage to tune the idle as we weren't too sure about the noise and wanted a second opinion (and no leaks all the time they were tuning, and pulling the accelerator cable etc).
Currently though the car isn't going anywhere so I could give it a tug, while trying to get the radiator out

[bmcecosse]

You have much more faith in that 'garage' than I have !!