Topic: How to seat needle jet down in carb body

[PennyDreadfuls]

I'm terrible at IDing these parts, so let's use pictures. 


(http://www.partzilla.com/images/diagrams/honda/134043/ILLUST/E1340/431801.png)

I was checking out the carbs on my 1977 Honda CB550K and unscrewed the [13] Needle Jet(?) and the [3] Needle Jet holder just fell right out (even though the other [3] Needle Jet holders in the other carbs are stuck firmly down in there). I dropped it back down into the carb body but it just won't seat right and allow the [13]Needle Jet to be screwed back down in.

It shouldn't take any "persuasion", correct? Is it a matter of getting it perfectly centered? What am I missing here?

[tomkimberly]

There should be a slot on the outside of the jet and a pin inside the bore on the carb body, make sure they are aligned.

Tom

[PennyDreadfuls]

I just realized there were more than one set of numbers on that diagram — here are the numbers outlined in red pointing to the parts in question:



This is the part that I can't get to seat correctly:



There's no slots or alignment marks on it, it is perfectly round and smooth.  In the other carbs, if I look down through the intakes, I can see the correctly seated parts poking through into the intake channel. This one just won't drop down through.

[iron_worker]

You probably will need to get some sort of wooden dowel and gently tap it into place with a hammer. Make sure you use something softer than the needle jet to press it in or you could damage it. Also, make sure you put it in the correct way. The tapered section should point up to mate with the jet needle.

Also, #13 is the main jet holder/emulsion tube. This piece, once threaded in, should hold the needle jet (#3) in place.

I think Tom maybe have been referring to the slide.

IW

[TwoTired]

Part 3 is normally pushed home by part 13.

Are the parts you are using Keihin parts?  If not, it's time to compare dimensions with what you took out, or look carefully into the seating area for a burr or foreign matter.

[PennyDreadfuls]

You probably will need to get some sort of wooden dowel and gently tap it into place with a hammer. Make sure you use something softer than the needle jet to press it in or you could damage it. Also, make sure you put it in the correct way. The tapered section should point up to mate with the jet needle.

Also, #13 is the main jet holder/emulsion tube. This piece, once threaded in, should hold the needle jet (#3) in place.

I think Tom maybe have been referring to the slide.

IW

That's great info. I'll use a bit of gentle persuasion and see how it goes. I can tell via the other carbs what the orientation is suppose to be so I should be able to get that right.

[PennyDreadfuls]

Part 3 is normally pushed home by part 13.

Are the parts you are using Keihin parts?  If not, it's time to compare dimensions with what you took out, or look carefully into the seating area for a burr or foreign matter.

Yes they are all original Keihin parts. I looked down in the seating area and didn't see any foreign matter in there but I'll check again.

[lucky]

Time to get the calipers out before something gets broken or stuck.

[tomkimberly]

You probably will need to get some sort of wooden dowel and gently tap it into place with a hammer. Make sure you use something softer than the needle jet to press it in or you could damage it. Also, make sure you put it in the correct way. The tapered section should point up to mate with the jet needle.

Also, #13 is the main jet holder/emulsion tube. This piece, once threaded in, should hold the needle jet (#3) in place.

I think Tom maybe have been referring to the slide.

IW

My bad, I was thinking of the emulsion tubes in Mukini carbs.

BTW, +1 on using a wooden dowen, or wooden chop sticks (time to go get some chinese food).

Tom

[PennyDreadfuls]

I ended up getting it seated using a bit more persuasion than I thought was appropriate, but it popped in — and on with the rebuild.

Thanks for the help. Cheers.

[iron_worker]

NP

Glad it all worked out.

IW