bing 64 carb, choke tube

[phintz]

Hello to everyone, I took my kitfox 6 over to my trusted rotax mechanic today to balance my carbs. I noticed a little rough idling and again on short final. We pulled the top engine cover off and behold my choke tube that threads into the top chamber of my left carb was popped out and not threaded in. This actually opened my choke some. This explains my rough idling. Now my question is , has anyone had this happen to them? I looked at CPS.com (california power systems) and I found the top chamber for $117 (part 961-250). The threads look like they are OK on the tube but look stripped on the chamber. My thoughts are order a new chamber and locktite that bad boy in. My father (retired farmer) wants to take the small tube to a machine shop and have a longer one made so the treads come through the bottom so we can put a nut (along with bailing wire and duct tape). Looking for another opinion. I would say this is not the best set up!

If anyone wants pictures I will get them!

Thank you like always,
Patrick
Kitfox Series 6
912uls/warp drive prop

[gregsgt]

My thought is that I can't see any way that could become stripped without someone over tightening the tube into the cap.

[kmach]

Yes ,I have had some problems with the bent tube threads and a carb top, usually from bumping the setup when it is tight while working on something else.
The carb tops have the metal throttle/choke plate attached to the carb top in two threaded "C"s. You can swap carb tops from side to side , once you remove the throttle plate, at the choke bent tube, and the bolt/nut at the front. This swap will give you usable threads on the carb top for the choke brass bent tube threads, the front of the throttle plate has a machine screw with nut so no threads really required.

If I had that happen again I would consider trying loctite 648 retaining compound, I have used that on other items and am very impressed with it.

[Av8r3400]

I agree with Greg. The only way this could happen is to have the choke tube either overtightened, cross-threaded or otherwise abused.

[phintz]

Not sure, possibly over tightened but I can't say. Thanks for the input

[cap01]

Had this happen also. Rather than replacing the carb top , welded a nut to the bracket. Now I don't have to worry about stripping that out.

[HighWing]

My father (retired farmer) wants to take the small tube to a machine shop and have a longer one made so the treads come through the bottom so we can put a nut (along with bailing wire and duct tape). Looking for another opinion. I would say this is not the best set up!

Patrick, I am retired, but not a farmer, but your dad and I think a lot alike.

My engine was a low time previously owned 912 from a pusher configuration. Lots of different stuff on the carburetors. I priced those little bent tubes and decided I could make my own. Thread length is only a matter of a little extra length and a couple of more turns on the threading die. I also lined the tube with some Nylon tubing - flared on both ends to secure it in place hoping to reduce the metal to metal friction - cable to tube.