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more carb questions :-(

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Todd
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more carb questions :-(

Postby Todd » Thu Jan 20, 2005 3:54 pm

Sorry guys! I cant seem to get this right! I rebuilt the carb, When i did I noticed there was a little gas in the float. I jsut adjusted for it and kept going. I plained it acording to Carls web page on the throttle body and where it bolts to the intake. (awesome directions BTW) and it leaked fuel, would only run with choke 3/4 closed and idel screw was in all the way.

So I went an bought a new float $18.00! a new idel tube (mine was a little kinked. and check to see if the carb was plane. I adjusted the float properly, I reseals the Main jet threads, sealed the basket threads.

Now it idles with the screw out 1 turn. doesnt leak ( not so far ) but still i have to leavce the choke closed! I check for a vacume leak, on the carb and on the itake by makeing it idle rough by openening the choke then i spray some carb cleaner in the throught and it smoothed out. So i put the aircleaner tube back on and spray carb cleaner all over the carb and the intake. No change in idle!. I am lost
i have a few tractor pics on my site i should have started taking them before i took it apart

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Bigdog
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Postby Bigdog » Thu Jan 20, 2005 4:21 pm

Todd, have you tried your leak test with an unlit propane torch? Use caution if you do this but I believe it is a better way to chase air leaks.
It is possible that there is a crack in the carb body that you cannot see.
Bigdog
If you can't fix it with a hammer, you've got an electrical problem.

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Todd
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Postby Todd » Thu Jan 20, 2005 4:27 pm

whats that test?
i have a few tractor pics on my site i should have started taking them before i took it apart

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Postby Bigdog » Thu Jan 20, 2005 4:39 pm

Use an unlit propane torch to check for leaks around the manifold, manifold gaskets, and all junctions of the carb and manifold. If you get a stream of propane near the air intake leak, the engine will smooth out. You can get the tip of the torch into places you can't see easily. Just be careful around potential ignition sources.
Bigdog
If you can't fix it with a hammer, you've got an electrical problem.

My wife says I don't listen to her. - - - - - - - - Or something like that!

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Todd
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Postby Todd » Thu Jan 20, 2005 4:40 pm

Thanks Ill check that next! This is killin me. Could an internal leak cause a problem?
i have a few tractor pics on my site i should have started taking them before i took it apart

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Todd
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Postby Todd » Thu Jan 20, 2005 4:45 pm

wouldnt the leak have to be on the intake section of the carb? even if there was a crack on the bowl side it should affect vacume?
i have a few tractor pics on my site i should have started taking them before i took it apart

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Postby Donny M » Thu Jan 20, 2005 4:51 pm

Todd,

Did you make certain that the main jet is clean :?: Is the choke completely closed while running :?:
8)

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Postby Jack Donovan » Thu Jan 20, 2005 5:55 pm

I had the same problem, Never found out what it was. However, the gasket between the upper and lower part of the carb , has to be good and seal. also i put a small "O" ring on the end of my air adj. screw, and soaked the carb good when reasembling it for the 1000 th time. Hope this helps. "Jack"

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Todd
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Postby Todd » Thu Jan 20, 2005 6:37 pm

the choke has to be 1/2 - 3/4 closed. If it is all the way open it will barley fire, and wont run at all. This makes me think if its a leak it a massive leak. The main jet is clean. The only thing i think may be a little fishy is the idle adjustment screw does not seem to bottom out solid. Its hard to explain what i mean, It just seems strange. In addition the idel adjustment screw i took out was very flat on the end. The fact that it idles well with the screw out 1 turn makes me think thats not the problem. tried the propain, does not seem to find a leak. Has anyone heard of a leak beweet the exhaust port and intake port on the manifold gasket?
i have a few tractor pics on my site i should have started taking them before i took it apart

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Postby Donny M » Thu Jan 20, 2005 6:44 pm

I suppose that is possible but the manifold would have to be in pretty rough shape and I don't think it would run very good at all. When it runs at an idle is the choke open :?: Did you replace the felt seals on the throttle shaft :?:
This gets frustrating I know, but with the help of the board you'll figure it out 8)

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Todd
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Postby Todd » Thu Jan 20, 2005 6:47 pm

i replaced all the felt seals, And it does not run at all with the choke open, at 1/2 choke it runs rought 3/4 choke runs smooth as silk. The top of the carb was warped slightly. I straightned it and filed it. seems perfect.
i have a few tractor pics on my site i should have started taking them before i took it apart

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Postby Donny M » Thu Jan 20, 2005 7:21 pm

Todd,
If you have a vacuum gauge put it at the pipe plug on the manifold and see if your getting good vacuum. That will tell you if there's a leak in the manifold 8)

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carb questions

Postby mike mix » Thu Jan 20, 2005 7:22 pm

Fuel level in the carb is set to a measured depth for a very important reason, the carb fuel level can have the same effect as changing the main jet size in a carb. When these carbs were calibrated and flowed during engine development, various jet sizes and float fuel levels are tested to get maximum engine performance.
Variations from the factory spec. cause problems. Set the carb adjustments to Carls directions if the engine health is good the engine will run correctly. P/S I work for General Motors and have flow tested carbs.

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Todd
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Postby Todd » Thu Jan 20, 2005 7:29 pm

I was just in the garage with the door shut (stupid I know) trying to figure it out. The exhaust was making my eyes water. My 9 year old Daughter walked in and thought i was crying cause i couldnt fix it :-). She said it would be ok!
i have a few tractor pics on my site i should have started taking them before i took it apart

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Todd
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Postby Todd » Thu Jan 20, 2005 7:50 pm

adjusted the float height perfect just checked it, also on the gasket i can see a perfect indent all the way around where it seals. tested with propain and carb cleaner for leaks. I checked the main jet cleaned it reinstalled.
Same problem. When the choke is 3/4 shut, runs like a top wont even start with the choke open
i have a few tractor pics on my site i should have started taking them before i took it apart


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