Leaking float chambers

I can't believe it's the August bank holiday, and all I've managed is a
too-rushed hack up & down M5 M6 to Falkirk & back in the rain six weeks
ago.

Latest joy with the Boxer has been knackered diaphragms and complete
carb re-builds (just when the weather's been nice - deep joy). I can
only hope it hasn't knackered the exhaust ports too - it happened some
way from home and I had to limp back 2-up at 50.

Now the wretched thing is dripping from one float chamber. I know it's
clean, flat and smooth around all the mating surfaces. I know it has a
brand new cork gasket. I know I didn't swap the bowls over by mistake
(they're handed anyway). I know I'm losing patience (and petrol).

I've bent the float arms slightly, which seems to help a bit, but I
don't want to overdo it and run lean/misfire when it's wide open.

Anyone got a favourite bodge (apart from Araldite)?

Regards,

Simonm.

 

SpamTrapSeeSig was seen penning the following ode to ... whatever:

A fake pound coin to a half-eaten doughnut that you've got dirt in the
petrol and/or worn float needles. Dripping from the float chamber on
ShiteOldBoxers almost *never* is a problem of the mating surface,
because the fuel level should get that high in the first place.

Here's what you need to do:
Order a set of new floats/needles/axles from Motobins or
Motorworks. While you wait for them, remove the petrol taps and clean
out the mesh filters in the tank. If you find red powdery residue or
flaky stuff there, you need to clean out the tank and remove the old
coating, because it's coming loose. Do whatever you need to do to the
tank, then put the taps back on. Fit inline fuel filters.

Replace floats, needles & float axles with the new items that should
have arrived by now. Do set the float height according to the
manual. While you've got the float needles out, clean out the seats
with really nasty carb cleaner - if the tank coating is coming off,
chances are that it's baked itself to the needle seats and will
prevent them from shutting properly.

Don't, that's not the problem.

Don't bodge them either, that'll end up costing a lot of dosh.

 

Timo Geusch was seen penning the following ode to ... whatever:

Grrrr. ^^^^^^ shouldn't, of course.

 

SpamTrapSeeSig was seen penning the following ode to ... whatever:

The problem with the float isn't visible, but the styrofoam-type
floats on these Bings have the nasty habit of getting heavier over
time. The ones on my GS looked perfect, just ever so slightly
discoloured. I bought new ones because I suspected a problem with the
floats, and the new ones were noticeably lighter. Appearantly the
float slowly soak up petrol, and the heavier they get the later they
close.

Also, the rubber tips on the float needles harden - again this isn't
visible - and this badly affects their ability to seal.

Don't I know that...

Put it this way - if you don't you've potentially got *two* different
types of crap coming off the insides of the tank. Can't be a good
thing. I'd do the job properly if I'd have to.

Forget about the needle seats - they hardly ever wear due to the
rubber tips on the needles. *If* the seat is worn I'd say you got more
overall wear in the carb than is good for it. I've *never* seen a worn
needle seat on these, and I've seen a few very manky Bing carbs.

 

SpamTrapSeeSig was seen penning the following ode to ... whatever:

Yes, but only if you get it right - there's a danger of making the
bike run to lean.

TBH I haven't used Petseal - my comment was more on the general
side. If you recoat the inside of the tank, not cleaning it properly
out would probably be a bad idea, especially if you have to get the
new stuff out as well...