Stripped threads in idle jet

[flameeater]

Hello all, been a while since I have been around here. A while back I tried to strip my carb (I can't tell if it is an authentic MS, or a very old replica, but it ran ok... It is cast iron instead of aluminum) When I got into it it seems that almost all of the brass was near fused to the cast. I managed to strip most everything down but when I finally got to the idle jet it just crumbled. I ended up drilling it out with some reverse bits. and I cleaned up the threads that were there with my tap and die kit.

Problem now is, I cannot get a new idle jet to screw in. The threads are there, and the tap I used is the right size according to the new jet I am attempting to install, but I think they are either stripped towards the top, or perhaps the threads that existed beforehand were bigger than the tap (the tap does seem a bit loose in the hole). I THINK, just by eyeballing this thing, that at some point someone JB welded the old jet in.

So 2 questions here...
1. Is there a way to save this thing? Has anyone had any luck using a helicoil or similar thread repair? Or would that just be a bad idea for a carburetor? I have never used one before.

2. I went ahead and rolled the dice on what is supposed to be a genuine carb, with the name on the bowl and all. I think I ended up paying around $70 or so after tax and shipping, but it will most likely need to be rebuild also. Any tips from you old hands with this thing so I don't screw up another idle jet hole (assuming it was not JB Welded, and I somehow screwed this up)?

I did try a cheap Chinese carb to see if it would get me by in the meantime, but apparently (and I tried 2 of them) they are only made to let your tractor put around on flat ground. If you need to go up hill you have to do it in reverse, what a joke. Carbs are not really a difficult technology, and I wonder why these newer replicas act that way. They close that float valve way to soon uphill. I may try to throw a set of brass floats in one and see if it improves at all, the new ones are plastic. Aside from the hill problems they both ran great. Tractor that can't pull a hill is useless to me though.

 

[Kondoge]

Chinese carbs ain't no good, they started using metric instead of standard on them or at least here in Canada they do as for why they run poorly its because they are mass produced as cheaply as possible, cutting corners to make it cheap. I might say depending on the rebuild kit the needle may be different thread? Could be that you are trying to thread a metric needle into a standard thread which works out not great.... never tried to repair the needle threads myself but maybe somebody else has. what kinda tractor you running 9N, 2N or 8N? if it's an 8N the carb could be a Zenith carb too.. most of the experts here are probably asleep about now.

as for only being able to go up a hill backwards that's just silly. Hey its a backward horse just gotta put a 3 point on the front no? (Joking) if it cant pull a hill imagine what it would do pulling an implement....

The Zenith carb

 

[flameeater]

Oh, yea I suppose I could have been a little more specific. Its a 48 8n. I think it is the tsx 33 (it has no markings or tags). If it is a replica it is much closer to the original than the current batch of aluminum replicas.

 

[Kondoge]

is it brass coloured?

 

[flameeater]

The carb itself is kind of black, looks like it used to have red paint on it. For sure it is the MS TSX line, not zenith.

As for the hill thing. I fiddled with it for a long while, and it is certainly a fuel delivery issue ( on the cheap carbs, not the one I am trying to fix). I let it die on the hill, and pulled the plug on the bowl, and only a small amount of fuel would come out. Pulled the line, and it flowed as pretty as you please. I adjusted the floats to .25 from the body (i think it is supposed to be .26 but I figured .25 would let them close a little later), and that did not help either. It actually would pull a scrape or box blade just fine... until the nose started to rise.

 

[flameeater]

The one I am trying to repair looks almost exactly like this one, aside from the name on it. Mine has no identifying marks at all that I can find.

 

[Kondoge]

I had one like that too but it was brass coloured, it was weird some days, Anyways. I would say you could try rebuilding the genuine carb using the Chinese carb parts or the rebuild kit you were going to use for the one you had to tap the threads in. if you already have a genuine carb I would fix that official marvel one.