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I rebuilt the carb off my father-in-law '47 Farmall -A today. It's a Marvel-Schebler TSX-157. I posted this here in hopes of getting more exposure to the thread. He said gas was leaking out of the carb so I said we might as well pull it and rebuild it. This carb was never off the tractor. I got a rebuild kit and a new set of floats for it because I thought either the needle valve was bad or the float had a hole in it and sunk in the bowel, thus not shutting off the needle valve. After I split the carb I couldn't believe my eyes. Look at the pics of the float to see why. Both floats are caved in like someone hit it with a hammer. Both sides of both floats are like that. After I removed the float I shook it to see if any gas was in the float. I couldn't here anything sloshing around in them, nor did I see any gas leaking from them. Has anyone ever seen this? What caused this? The tractor never sat outside. It's always in the barn and it's ran year round. Check out these pics... any thoughts?? :trink39:
 

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Wow!! Thats one for the books,,,lol.

Either heat or cold caused it. I'm no expert but,,, I know gas expands in the heat,,, have you ever left a sealed gas can in the sun??
No sure where you are from but if it was left in the hot sun I think it is possible to put that much pressure on the float. Sure wouldn't think the bowl would /could be pressurized ,,,,but maybe.
Water in the gas tank and bowl could cause it too,,but seems you would have other signs of that. Lets say the bowl filled with water and froze,,crushed the float. (very possible) Where did the water go?? Is there any signs of corrosion,,cracks in the bowl?? And how did it get in there if kept in barn?

I think heat is a fault and you have the ONLY carb that built up pressure from it!!! 1 in a million!!! lol


It's pretty cool though. Use them for wind chimes or hang from mirror in car!! lol
 

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My vote is for water freezing in the carb.

If heat caused it, I would think the floats would have exploded instead of imploding because the float is a sealed environment and constant humidity on the inside. The heat would have had to heat the float, push air out, have something seal the hole and then cool to create suction causing the collapse. Freezing would just have to have water enough to slowly crush it.

Also, since there is no water or gas in the float itself that tells me it wasnt enough pressure to explode the carb body but just enough to compress the air in the thin brass floats.

Since it was original since 47, someone MAY have taken the carb off at one point, brazed the float (causing air to be heated on the inside and then cooled) changing the humidity level in the float and over the years gradually contracted and crushed the float and just adjusted the carb as the float changed. Not uncommon to repair a float in 1947.

1947 (for some of us) is so long ago, its not hard to forget the little "..Oh yeah. Seems to me I DO remember old George having to do a field repair in 1952 on that thing to finish getting the field done.....".

I do have to say though, it is an awful symetrical "crush".
 

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"Both floats are caved in like someone hit it with a hammer. " Yup. That's how they adjusted the float level at the factory. Some floats had too much 'lift', so they'd whang them with a hammer to reduce the effective volume, and the float would sink further into the float bowl, raising the fuel level. Just heat 'em up to pop them back to original shape if you got the float dropped too far.

Oh, and I have a bridge for sale in the San Francisco Bay area. Real nice 'gold' colored and freshly painted...

My first look said squished by freezing water in the float bowl. Heck, they're a just a bit older than I am, and I know I've forgotten stuff I've done in the last week, much less last 64 years. I'd bet they got frozen, damaged, and before it was known, the fuel/water in the bowl was drained the 'next day...', so there was no corrosion,' and the damage was done and unseen. Remained that way for years until some fool went lookin'...

tom
 

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"Both floats are caved in like someone hit it with a hammer. " Yup. That's how they adjusted the float level at the factory. Some floats had too much 'lift', so they'd whang them with a hammer to reduce the effective volume, and the float would sink further into the float bowl, raising the fuel level. Just heat 'em up to pop them back to original shape if you got the float dropped too far.

Oh, and I have a bridge for sale in the San Francisco Bay area. Real nice 'gold' colored and freshly painted...

My first look said squished by freezing water in the float bowl. Heck, they're a just a bit older than I am, and I know I've forgotten stuff I've done in the last week, much less last 64 years. I'd bet they got frozen, damaged, and before it was known, the fuel/water in the bowl was drained the 'next day...', so there was no corrosion,' and the damage was done and unseen. Remained that way for years until some fool went lookin'...

tom
Your post is confusing,,,but I think it is because some editing has been done to other reply's.
 

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My vote is for water freezing in the carb.

If heat caused it, I would think the floats would have exploded instead of imploding because the float is a sealed environment and constant humidity on the inside. The heat would have had to heat the float, push air out, have something seal the hole and then cool to create suction causing the collapse. Freezing would just have to have water enough to slowly crush it.

Also, since there is no water or gas in the float itself that tells me it wasnt enough pressure to explode the carb body but just enough to compress the air in the thin brass floats.

Since it was original since 47, someone MAY have taken the carb off at one point, brazed the float (causing air to be heated on the inside and then cooled) changing the humidity level in the float and over the years gradually contracted and crushed the float and just adjusted the carb as the float changed. Not uncommon to repair a float in 1947.

1947 (for some of us) is so long ago, its not hard to forget the little "..Oh yeah. Seems to me I DO remember old George having to do a field repair in 1952 on that thing to finish getting the field done.....".

I do have to say though, it is an awful symetrical "crush".
You edited your post. LOL But I think you nailed it!! The soldering or brazing is more likely a cause. Seems logical to me!!!
 

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I have found floats in some of my small engines that were collapsed in much the same manner,probably by water from condensation that froze ,then evaporated before I discovered the damage months later--I have also caused the same thing to happen when I used compressed air blown into the fuel line in hopes of removing a clog too!...
I wont do that again...

I doubt 21" of engine vacuum could "smash" a float,but maybe if the engine was racing along and someone put their hand over the carb inlet or something blocked it in similar fashon,who knows??..
 

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As Tractor-Holic said I've read that compressed air into a blocked carb can collapse the float.
 

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Discussion Starter #11
Hey guys thanks for all the replies. Just a little background about the tractor. My father-in-law lives on the small farm he grew up on. As a young lad he helped his neighbor with his small farm because he was getting up in years. In '47 his neighbor bought this Farmall A brand new. After owning it for a few years he told his wife that if anything happened to him to give the tractor and all the accessories to my FIL. A few years later my FIL's neighbor passed away and his wife gave the A to my FIL. He's been running it ever since. I'm not sure what could have caused this. I asked him if he ever had water in the carb and he said he never did. So let me ask this question; if there was that much water in the carb bowl that froze and collapsed the floats wouldn't there have been issues with the tractor not running right? Compressed air.... I'll have to ask him about that one to see if he ever did that. Here is something a co-worker said after I showed him the float pics. He thinks that back-firing could have caused this. Some how excessive pressure got back into the carb. Anyone have any thoughts about the back-firing theory? Would or could the float bowl be pressurized during a backfire? I know the tractor backfired from time to time. but hasn't done that for a while now. This is interesting. Thanks for everyone's input. :trink39:
 

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Your post is confusing,,,but I think it is because some editing has been done to other reply's.
The 1st paragraph was an attempt at a folksy joke. The second sentence was the key to telling that...

The third section is an actual analysis of what I thought happened. It got squished one early fall when a quick freeze came through, and there was water in the float bowl. The next day, closing the barn door after the horses got out, the float bowl was drained for winter storage. The damage that was done was never discovered as the float was not perforated, and continued to work. Until it didn't shut off the fuel flow any more.
tom
 

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The 1st paragraph was an attempt at a folksy joke. The second sentence was the key to telling that...

The third section is an actual analysis of what I thought happened. It got squished one early fall when a quick freeze came through, and there was water in the float bowl. The next day, closing the barn door after the horses got out, the float bowl was drained for winter storage. The damage that was done was never discovered as the float was not perforated, and continued to work. Until it didn't shut off the fuel flow any more.
tom
LOL. I see now,,,but at the time,,,for some reason I could not see the original comment you quoted. It was not there. Must have been a timing thing,,but I logged in later and it was there. Made more sense then!!
It's all good.
 

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I've seen floats collapsed like that from compressed air blown into the carbs, as TH said. Not that uncommon. Freezing water might crack the bowl, too...
 

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Wonder if it has a VERY miniscule leak. It could pass air but not liquid. So the float air expanded when it got warm and 'pressed' the air out. When it cooled it was sealed by the gas. Each time a bit more air would be pressed out. Over time it slowly collapsed. Suppose you dunk it in some warm water. Watch if it expands or if bubbles form. If nothing. slowly raise the heat. If it starts expanding then remove it from the water. I expect bubbles will form before it expands....
 

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I don't have a pic but my Tec OH 160 float was dented really bad the mechanic said that water in fuel froze that's why dent was on bottom only, makes sense to me.
 

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Discussion Starter #17
Thanks everyone for the replies. We were working on the A Sat morning when I asked my FIL if he ever blew any compressed air in the carb or fuel lines. He said he hadn't. So knowing that, I'm going to go with water in the gas froze and smashed the floats. The wall thickness of the float bowl on the carb is around 1/4" thick iron, so if water froze it would have pushed in the sides of the thin-walled brass floats. :trink39:
 

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Then the air in it is compressed. I wonder if putting it in water and slowly warming it up would bring it back to shape....
Add some noodles and you'd have soup. Unless you're on a low-carb diet....

:sorry1:
 
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