Carburettor Rebuild Time... Help!

[Drew400]

Hello all,

Time for your expert advice on a different topic please - carburettor rebuilding.

I have inserted an image to support my questions.

The bits have all come back from cleaning, plating, etc. and are gagging to go back together. However, both my manual and my photos are slightly inadequate to help my lack of experience and memory!

I recall pulling out the main jet with the leaf spring and after that the needle jet 'fell' out of the carb body. However, I'm trying to put them back and the needle jet will only go in as far as (i.e. flush to) the bottom of its channel in the carb body. Thus, there in not the space to push in the main jet behind it. Naturally, I don't want to force it as that would presumably mean it won't fall out again if I invert the carb body. Is this making sense?

Also, my set of carb gaskets from David Silver includes some small ones (o-rings really) that I don't know what they're for, Do you?

Thank you all in anticipation of further help to my (increasingly) long-term project.

D.

[Trigger]

Drew, Number 2 is correct (not sure if the is round the right way)  But, have you changed the O'ring on the main jet? One O'ring is for the main jet. One is for the air screw . You will need two on each side of the T pipe that is the T pipe that goes between the carb body's. You should have one on your float body. And one is for the drain screw.

[Drew400]

Thanks Trigger, much appreciated.

Any thoughts on why my needle jet won't slide in far enough to allow the main jet to slot in behind it?

Cheers,

D.

[Trigger]

Drew, i think you are on about the tube? Try putting it in the other way. I can not see clear from your picture, its not you its my eyes. The jet only goes in upto the o'ring and then the leaf spring holds it in.

[Drew400]

Yes indeed (the tube with all the holes in its side). I've tried both ways, although the way I've photographed is the correct way, I believe. If it would go in a bit further there would then be space to insert the jet, as you say, up to the o'ring. I'm very reluctant to push it in harder! Hmmm.

p.s. Delayed reply due to watching another Marquez MotoGP win (at least the first 12 laps were exciting!).

[Norniron]

Insert it like this pic

[Trigger]

The 400 expert has made his comment

[ewanhughes]

Have you seen this before Drew?
It really is the badger's nadgers of carb rebuild documents!


http://www.docstoc.com/docs/97200467/CARB-REBUILD-101

[Drew400]

Thank you again, all.

Cheers,

D.

[Clem2112]

One thing 

The airscrew has no O ring .... Just the spring.

[Clem2112]

O rings are for the main jet, float valve and the drain screw. The 4 larger ones are for the fuel feed connector tubes or the inlet tee.

[Drew400]

Thanks again, I'm now clear on the gasket set.

I'll have another go at inserting the needle jet tube in the next few days. Maybe it's just a bit of a tight fit after the carbs were cleaned, but it's still a source of slight worry to me (I don't like pushing hard on carb bits as they all seem so delicate!).

Cheers for now,

D.

[Trigger]

Spot on Clem. You are right about the air screw. Drew, wipe a little Vaseline on the tube to see it it will slide in. Has the tube been cleaned?

[Drew400]

Thanks again Trigger,

I have cleaned the tube only with petrol and airline, but the carb body has had the full sonic and vapour blast treatment.

I'll try the old Vaseline trick when I next get into my garage. Sadly, the day job gets in the way of the rebuilding classes, eh?!

Cheers,

D.

[Trigger]

Drew, the tubes need to be nice and clean and all the holes checked. As Norniron once said, You may think that they are clean but, have a look with a microscope. He was right.