Stripped Carb Main Jet?

Paul007

Member
Pulled the main jet needle out of my '59 202 today to spray some carb cleaner down the hole and when I re-installed it just drops in all the way, like the threads are stripped. No difficultly in removing it, and I have adjusted it in the past by closing it gently and reopening and turn or two. I can't figure out why now all of a sudden I can't get the threads to catch. Is there something that could have come loose inside the carb? Continental 4 cylinder (gas) with updraft carb.
 
Paul,
"Is there something that could have come loose inside the carb?"
I don"t think so. My Ford 8N and my "65 MF202 both have M.S. carbs on them. The main or high speed jet is threaded into the carb top, if I"m not mistaken.
Can you see the body threads in the carb? How do the threads on the needle look? Spring in place, not that that should matter.
It"s been a while since I"ve had one of my carbs apart, but I"ve never run into this problem. I guess it would be possible for the brass needle threads to strip, or even the cast carb threads for that matter. Got me to thinking now...
Hopefully someone will come along shortly to help out, I"d like to know.

Roger
 
Thanks for the reply Roger. I can't see the threads in the carb, maybe with a dental mirror and light, however I'm back home and it's at my ranch 25 miles away. The brass threads on the needle look fine except for maybe 1-2 threads about halfway down, which I assumed is where the end of the spring was wearing on it. There must be more thread than that in the carb body? Are those threads cast iron? I could feel the threads skipping over (like running a comb over a table edge) when I tried pushing the needle back in, I just can't imagine they went from OK to that without any hint of binding or trouble coming out. No evidence of thread material from the carb on the needle threads.
 
It is probably not lined up correctly. I have done something similar with mine, it is possible to get it in there and not lined up. Pull it back out and try again.
 
Thanks for the reply Roger. No problem...

[i:b33ed8a7dc](I can't see the threads in the carb, maybe with a dental mirror and light, however I'm back home and it's at my ranch 25 miles away.)[/i:b33ed8a7dc]

I went out and looked at my 202 this morning, and I can see why. Very hard to see with the loader frame in the way... So, I looked at my 8N, similar carbs, different models, but same high speed needle adjustment.

([i:b33ed8a7dc]The brass threads on the needle look fine except for maybe 1-2 threads about halfway down, which I assumed is where the end of the spring was wearing on it.)[/i:b33ed8a7dc]

Looks can be deceiving!! The needle threads should be clean and sharp. That is a brass needle and should wear before the carb body does. The wear might possibly be from where the washer and gasket has worn it.

[i:b33ed8a7dc](There must be more thread than that in the carb body? Are those threads cast iron?)[/i:b33ed8a7dc]

Yes and yes.. The cast carb top is drilled and tapped for the needle and appear to be at least 1/4" or more deep into the casting.

[i:b33ed8a7dc](I could feel the threads skipping over (like running a comb over a table edge) when I tried pushing the needle back in, I just can't imagine they went from OK to that without any hint of binding or trouble coming out.)[/i:b33ed8a7dc]

That's not good. Like I said, inspect the needle threads closely, if it feels like a comb going over a table edge, chances are, they've flattened out, not hard to do with a brass screw. Probably been wearing a long time, depends on how much adjusting has been done in the past.

[i:b33ed8a7dc](No evidence of thread material from the carb on the needle threads.)[/i:b33ed8a7dc]

That is good, but being that the carb body is cast, the needle should wear first anyway.

Paul, I don't want to be misleading, all this info is based on your carb being the Marvel-Schebler TSX series. I looked at my carb, and my 202 parts manual. If you have a different carb, like the Carter that was also used, then things will be a bit different. My suggestion is that you go ahead and pull your carb so it's easier to look at / work on. If it is the M.S. Carb, then this site sells the major rebuild kit for it that comes with a new high speed needle, gaskets, bushings, etc...

Good luck and let me know what you find out...

Take Care,
Roger
 
Thanks all again for the advice (I thought about the teflon tape, right up my alley :).

Heading back out today for a better look, will report back tonight.

I didn't mention that the root of the problem I was chasing turned out to be the ignition condenser. Would start right up but miss under load. Popped in the condenser out of my '54 Intl pickup and cured the problem. The carb issue is collateral damage...
 
(quoted from post at 20:57:10 07/08/14) It is probably not lined up correctly. I have done something similar with mine, it is possible to get it in there and not lined up. Pull it back out and try again.

Bingo. Went out there today, pulled it out (without unscrewing), wiggled it around a bit and it screwed right back in. I have a loader also so you can't really get to where you can see/align it easily. I still can't understand how it would go all the way in without threading, then go in another direction and thread in fine. Anyway I'm good to go. Thanks!
 
Yeah, the loader does not make things easy! I got a TO35 since getting the 202 and man, they are a joy to work on without a loader in the way.
 

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