I'm looking for a carb part that broke on the rebuild of my 72 roundtop 3 screw carb .  I've attached a few pictures. The picture with the red arrow is showing the front carb. I actually need the part for the rear carb.  Not sure if there is a difference. The other picture shows the actual part that I need.  If you look at the bottom of the part you can see that it has broken off.  It appears to be some sort of plastic.  The choke linkage attaches to this.  I have the linkage.  I thought about trying to epoxy it back together but since it moves anytime the choke is on, I'm not sure how well it will hold up. Any help would be greatly appreciated.

Thanks
Paul

Try reaching out to Z Therapy to see if that's a part they stock. I think it's part ZT154. https://ztherapy.com/products/masterprices/master_price_list.htm

It looks like 72 nozzles are rare to unobtanium on the open market. MSA has 4 screw nozzles.

Someone more knowledgeable than I am will have to advise more.

 

 

There's no way I would trust epoxy on that. You need a replacement.

and if you replace one, I would replace both. Even though they might be expensive. They tend to have some wear in the orifice and a matched pair will be easier to tune and get running right. I might also consider replacing the needles too if they show any signs of rubbing

Thanks for the info guys.  Ordered a pair from z therapy yesterday.  Pricey, $120 / pair, but when your this far into a restoration what's another $120. On a related note, if the one on the front carb comes off without breaking, I'll have a used nozzle available it anyone needs on.

When you install the new nozzles be sure the attachment points on the choke linkage (flat bar with bent ends) are exactly parallel with their mounting points. The linkage piece frequently needs a bit of a twist on one end or the other to re-align it. Misalignment will cause the nozzles to stay down in the choke position.