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Discussion Starter · #1 ·
I recently picked up a '72 TNT 440 F/C for $60 and after some tinkering I got to run. However, after I start it, it will rev way up out of control without me touching the throttle. I was just wondering if someone could point me in a direction to get it fixed. I think it just may need a carb cleaning, but could it also be sucking in air from somewhere? Thanks for any help!
 

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your sucking air from somewhere. most likely crank seals
 

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Discussion Starter · #4 ·
It's a single Tillotson H.D. The motor was rebuilt by the guy who owned it before the friend I bought it from, but it did sit outside for a while.
 

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TheFastMan said:
I recently picked up a '72 TNT 440 F/C for $60 and after some tinkering I got to run. However, after I start it, it will rev way up out of control without me touching the throttle. I was just wondering if someone could point me in a direction to get it fixed. I think it just may need a carb cleaning, but could it also be sucking in air from somewhere? Thanks for any help!
It could be a bind ing or incorrectly adjusted throttle cable...could be incorrect float levels..dumping fuel into the ports..could be.......
 

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Those carbs need to be rebuilt often.
Clean them good and use a good kit. I usually just change the gaskets,diaphragms.
There's lots of parts to these carbs.

unhook/loosen your throttle cable, see if it runs slower or turn the screw out that adjust your idle.

here's some hlp..
http://www.aerocorsair.com/id27.htm
 

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Check the carbs, intake and heads. If there is any thing in there, even if it is a small piece of a leaf. that could be you problem.........
 

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its the carb. tilly HD carbs are finicky, especially if it hasnt been cleaned really good or rebuilt in a while. have you tried adjusting the high and low needles? how about throttle cable tension and the idle screw?
 

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i would try adjusting your throttle cable or your idler screw first before anything. [thumb]
 

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Discussion Starter · #10 ·
Thanks for the input, guys. I'll play around with it a little more. When I choke it, it dies out so I think that eliminates the air sucking.
 

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Discussion Starter · #12 ·
I took this sled up to my uncle's today and we tinkered with it. The carb is fine. We did a compression test and the clutch side was about 25psi lower than the recoil side. We then found gas on the side of the motor near were the crank case splits. So, it's sucking air from the crank. Thanks for the input, guys.
 
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