Wanted - XS1B BS38 carburetor bowl

[Sarilhos]

Hi;
Just run in some bad luck, pilot screw is so seized, i'm unable to take it out.
Now it has a screw extractor broken inside.
I think it has no salvation.

So I'm looking for a carburetor bowl, for my XS1B, late model;

It's like the one in this thread :
http://www.xs650.com/media/albums/carbs-xs1b-1971-detail-pictures.2667/
http://www.xs650.com/media/xs1bcarbs-017.22714/

PS: anyone had any luck in fitting some hellicoil ?

Thanks

 

[TwoManyXS1Bs]

Rare part. That may be difficult.

Are you talking about the Pilot Jet?

There *may* be another way to save it.
The pilot jet sets atop and inside the "pilot well".

Carefully drilling straight down and centered into the bottom of the pilot well may give you access to the backside of the pilot jet.

Start with a small drill, just enough to be able to get a small diameter punch in there, and punch out the broken extractor.

The hole can be plugged later with sealant and a small ball bearing...

 

[Sarilhos]

Resume of what i did, maybe it can be use as a do and don't do, guide.

while trying to refurbish my carbs, only one pilot came out as it should.
The 2 mains and the other pilot where sized and unable to use a screw driver to take them out.

The 2 mains I used a torx screw pointer and a little tapping with a hammer and they came out nicely.

The sized pilot I tried the same method use for the mains, but it bend the torx point,
then I use carb cleaner, WD40, heat ( tried cycles of heat and ice to see if it would break the sized),
always using a torx to try and take it out, and no result.

Finally decided to use a screw extractor,
tried it several times (heat and no heat), until it broke inside the pilot



Now I'm trying to drill without doing to much damage,
it's timely process, even broke the smaller drill (need to buy a new drill, to finish),



I think that in the end I will no longer have threads to put the new pilot.
But thinking on adding this M5 thread insert.


If i manage to succeed,
still have two problems to solve (any suggestion, will be gladly accepted):

1- the thread insert is M5, 5mm and the pilot jet is 4.9mm,
so there's a little amount of play for the jet , when screwed inside the thread insert.
it's probably not sealed enough between the treads, probably some gas will pass.
Any type of sealant that it could be use to help with this ?

2 - how to set the correct height of the pilot to the bottom ?
In an original situation, is the pilot screwed until it touch the bottom ?
what would be the height from the bottom of the pilot to the bottom of the pilot well ?

Carbs are a critical part, and getting good ones fine tuned is hard.
now I have to deal with a not perfect seated pilot ....


PS: TwoManyXS1Bs, thanks for the previous post.

 

[TwoManyXS1Bs]

Okay, how about a second crack at that pilot jet.

Member Jsmith1107 had the same problem, stuck pilot jet.
Study the picture of his successful extraction in post #7.

http://www.xs650.com/threads/need-bs38-float-bowl.48906/#post-498578

Notice that his pilot jet fractured in the weak zone of the air bleed holes.


The two parts of the jet causing the tightness are the threads, and the 45° sealing tip. Those two create a locked condition.

Note the location of the air bleed holes.


Also, be advised that you want to avoid any procedure that damages the 45° cone-shaped sealing surface.


With all that in mind, you may be able to weaken the area of the bleed holes with a tiny drill or dentist's bit.


Sufficiently weakened, the jet should crack mid-body, freeing the threads from the binding of the 45° surface. Once unthreaded, the separated tip should simply fall out.

Just a thought...

 

[Sarilhos]

Thanks for those great tips.
I've bought 1,2 and 3mm drills to try and break the pilot jet.
still fighting to drill through the broken screw extractor (trying to not cause any more damage, so its very slow)

If the jet is pressed against the metering orifice (the 45º degree critical area),
that answers to my n2 problem described above.

 

[TwoManyXS1Bs]

Here's some more pics of the pilot jets.

Note the ring-shaped contact mark on the used/original jet.

I believe that the opening in the bowl, at the bottom of the pilot well for the 45° seat, is close to 2mm (0.080"). If you decide to do the "drill thru the well from the bottom" routine, I'd recommend just doing with a 1mm (0.040"), or, if necessary, 1.5mm (0.062", 1/16"). You'll want to drill through the pilot jet orifice, which will be about 0.45mm, and will help to keep the drill centered. Once drilled, a 1 or 1.5mm long punch or drillbit can be used to tap out the broken extractor...

 

[Sarilhos]

Hi;

So I'm still failling to drill out the old pilot with the broken screw extractor,
broke a few 1mm and 2mm drills, I decided to stop and take it to a professional turner.

Mean while I found a carburetor with the bowl that I needed in UK and receive it today;
I've read the the threads in this forum on how to identify carburetor's;

When looking to the Photos of the carburetor that was for sale in UK,
I've notice that the carburetor was differente from mine,
but I was 100% sure that the bowl was the one I needed;

So I thought maybe this is some European special that was not in the threads.
But it was not;

After a closer look, the carb is from a 72/73 model,
but someone manage to fit a 70/71 bowl, damaging the carb but not the bowl .... Lucky me









They just remove/broke the little brass tube on the bottom boarder of the carb, above photo
and did very little trim on the bowl side so it could fit, bellow photo



My bowl to the new carb



Thanks for all the help;
If I manage to save my bowl, I will keep you posted.