Right what I'm going to do now is remove the main jet and the pilot jet. Pilot jet is little
bit awkward, it's right at the front, you'll see in a moment. But we'll whip these both out now.
Now we've removed the main jet, we can just blow this out of an airline. I think it's
clear but we'll just give that a blow through. Just slightly, it might just have some fuel in there maybe.
That is nice and clear.
We're going to change this fibre washer to a dowty washer. Dowty washer has a rubber
seal on the inside of a metal washer. The fibre washer is fine when they're new, and maybe a new
one might help. But on this carburettor, when this was in place, I noticed when we put fuel in the tank
we were getting a leak. We pulled it up tight, the whole fitting, and we're still getting the drip. Now
you've got to be careful, you don't want to mess about too much with this height, it has to be correct.
But what I've found works really well, if you find you've got a persistent leak,
and the trouble is that people will over tighten this and you're going to strip that thread
out in that carburettor. Do away that fibre washer, and put your dowty washer in. And that rubber seal
will stop that fuel from coming through. Just make sure it goes on properly.
Actually I'm just going to wet that just a little bit,
round there. And put it on there, just as put it on just spin it round. And you can see you've got a nice
rubber lip seal on there. We'll put that back in place and that won't leak.
Just make sure that your carb needle, your slide needle, is in the top of the emulsion tube.
And screw up.
We've got a new dowty washer on there. We won't over tighten
that, it shouldn't need to be over tight.
Now we've got the main jet assembly back in place we're just going to take out the pilot jet.
See here, this assembly. This outer nut comes off, and underneath there is the actual jet itself.
Right now we've got to take out the jet itself, so it's easy to use a torque drive out of a little
socket set which has got a screwdriver straight blade. Small ring spanner. Hold it up and just
crack that off. It won't be tight, just pinched. Because it's brass it shouldn't be over tightened.
And as you can see now we're unscrewing, there is a fibre washer which you don't want to lose.
Just keep your finger on the bottom of your screwdriver bit, it's easier. Unscrew it.
and then your assembly comes out. We're just checking the pilot jet. Now this is quite a small
jet. This is the one that will block most easily, and you'll find when you try and start a bike,
you'll tickle the carburettor or give it lots of choke, and it'll fire up. And as soon as you
take it off choke, or after tickling it it's running clean, it won't pick
up. You'll find that your revs, they won't pick up, and you'll probably adjust your pilot jet itself,
the adjuster side of it, and you won't get any response. Because this
controls your lower rev range. This controls it until it picks up on the main slide.
So when you open up the throttle, lift the slide, the needle comes up, then you start to
draw fuel into the venturi and that's on your main needle. But your slow running
is all through this little jet, it's all metered through here. It's a very tiny bore so we make sure it is
clear. Actually I can't see out of this at the moment so we'll use an airline and we'll just blow it out.
Yeah we can see daylight through now, but it is tiny.
Pull it finger tight. We'll just nip that with the spanner.
So we've blown out the pilot jet and also the bottom nut,
I've blown that out as well. Just make sure there's nothing collected in the bottom.