Troy-bilt B&S model 12av566n711 won't start !

[PissedOff]

So I have picked up this mower out of an auction, and it was mistreated and abused.

I have cleaned the carb with spray cleaner and blew out all the orifices with compressed air. ( haven't soaked it yet, going to try it soon)
Cleaned the air filter, about to buy a new one (doubting this is my problem tho)
Purchased a new spark plug and tested it to make sure it was actually sparking
Changed the oil and drained gas and refilled with fresh.

This is the auto prime/choke model and without these options in my control i am a fish out of water. Not sure where to go from here, have tried about anything i could think of. ( and i am pretty savvy with this stuff, not small engines but i do all my own car work. Swapped out engines and everything so this shouldn't be so difficult.)

Motor only chugs when i pull the cord, doesn't seem like the fuel has enough air or spark. But i tried starting it with no gas cap, no air filter, no exhaust, and no intake. All useless, also tried to mess with the auto prime and choke controls but those did absolutely nothing as well. Noticed the head bolts... i guess were a bit loose so i snugged those up, wondering if the rings might be worn or something is wrong with piston. The spark plug does have fuel on it, when i pull it out after trying to start.

Dunno what else to say, but please help me.

 

[Rivets]

Please post all three of the engines numbers, model, type and code.

 

[PissedOff]

Gas tank is removed at the moment.

 

[Rivets]

See you won't post the engine numbers, all I can suggest is that you do a goggle search " How to adjust Briggs auto choke".

 

[DaveTN]

With the engine "chugging" and not revving up as it should, it could be getting too much fuel (wet plug). Look on the back side of the tank near the spark plug. On that metal bracket that supports the throttle plate, you should see a hole about 1/2" wide. Take a screwdriver and turn the adjustment screw inside clockwise about 1/8 turn then try to start it and see if it helps. Start it first if you can, then adjust the screw. If you can get it started, turn that screw a little at a time clockwise until it runs better! Also a weak spark could cause it not to burn the fuel efficiently. Take the filter off and put the bolt back down in the hole where it holds the filter on. Clean your plug and give it another pull. A weak plug will get fire outside the engine, but under compression it won't, and will either run weak and sputter along, or quit entirely after fouling out. What color fire are you getting on the plug? Should be blue-white color, not reddish-orange which would indicate weak fire. Might want to check the carburetor to tank gasket. You'll have to remove the tank bolts in order to pull the tank out far enough to get the linkage off. With the tank completely removed, then take the carburetor off and check it. Clean the diaphragm or replace it as it may be old and brittle and not flexing as it should. But try adusting it out first with the screwdriver above the back of the fuel tank and see if that helps.

 

[Ifixdit]

So I have picked up this mower out of an auction, and it was mistreated and abused.

I have cleaned the carb with spray cleaner and blew out all the orifices with compressed air. ( haven't soaked it yet, going to try it soon)
Cleaned the air filter, about to buy a new one (doubting this is my problem tho)
Purchased a new spark plug and tested it to make sure it was actually sparking
Changed the oil and drained gas and refilled with fresh.

This is the auto prime/choke model and without these options in my control i am a fish out of water. Not sure where to go from here, have tried about anything i could think of. ( and i am pretty savvy with this stuff, not small engines but i do all my own car work. Swapped out engines and everything so this shouldn't be so difficult.)

Motor only chugs when i pull the cord, doesn't seem like the fuel has enough air or spark. But i tried starting it with no gas cap, no air filter, no exhaust, and no intake. All useless, also tried to mess with the auto prime and choke controls but those did absolutely nothing as well. Noticed the head bolts... i guess were a bit loose so i snugged those up, wondering if the rings might be worn or something is wrong with piston. The spark plug does have fuel on it, when i pull it out after trying to start.

Dunno what else to say, but please help me.

It's hard to tell from the pics but it appears as though the tabs next to the two 1/2" head muffler bolts have been opened which means someone probably has messed with the auto choke at some point. If you take the muffler off you can gain access to the auto choke. It should be chrome looking and have a slot to slide onto a grey lever that goes to the carb side of the engine and is attached above the carb butterfly with a 1/4 inch head screw. If you grab the lever above the carb you should be able to open and close the choke. That will at least tell you that it is mechanically hooked up properly. Unfortunately I don't know how to diagnose if it is malfunctioning other than to start it up with the filter cover and filter removed and see if the choke opens when it starts up and the heat from the muffler hits it.