intek 20HP 31p977 0575 E1

2ball

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So my junkyard replacement engine starts, runs and cuts grass.

I did nothing to the engine but remove it from the old riding lawn mower and put it on mine and hooked it up. I did not clean the carb.

1. It smokes when I run it with the choke, but is calms down and runs great when I move the throttle off of choke.

2. it is dripping gas from somewhere near the carb. To me it seems like its dripping from the vacuum tube that comes from the carb.

Do both of these issues sound like a dirty/clogged carb/bad float issue?

if so, what is everybody's thought on the cheap Chinese carbs?

something like this?


I know I could just clean the original one, and I do have a spare off the old engine in case I break something.

or a Chinese rebuild kit

 
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Scrubcadet10

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check the oil level in the motor. smell it for fuel on the dipstick.
 

2ball

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I'm going to say yes the oil smells like gas. not overwhelmingly though.
 

Scrubcadet10

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be sure to drain it and refill it, with fresh oil.
may need to replace the needle and seat in carb. what's the engine model number?
 

2ball

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Having trouble finding anything on the engine,
i did find

Family YBSXS.5012VP 274826
17.5 I/C
 

Scrubcadet10

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Usually the model numbers on I/C engines are on a metal tag riveted to the metal housing right on top.
 

2ball

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Thanks for all of the help so far.

I just thought of something, the battery on my tractor is dead, I jump start it.
Could the carb leaking gas have something to do with the anti backfire valve on the bottom of the carb bowl?
it needs electricity to work, so when I turn my tractor off it does not work.

also I still need to check for the model number, Im not home to look yet.
 

lefty2cox

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I'm going to take a stab at this so someone else could correct me but I think the anti-after-fire solenoid just stuffs up the main jet when you turn the key off. It uses current to open, not close. A spring closes it in the absence of current. It only keeps fuel from being drawn up the main jet against the low pressure in the venturi created as air is sucked through. I believe there are other orifices, such as idle circuits and such, that fuel can still go through if the needle has not seated. The whole system is mounted below the gas tank. Also, I don't think the anti-after-fire solenoid's little rubber plunger under spring pressure is a match for the entire tank of fuel subject to gravity pushing on it. If I'm right, I'll be very excited as I'm not a pro.
 

Scrubcadet10

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Correct that solenoid won't keep the engine from flooding when the needle fails
 
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