410 cultivator not running right

gmacmopar

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Hi all, my neighbor brought over his little bolens 410 cultivator and it will only run on full or half choke and that is wide open. I checked the throttle cable, spark arrestor, plug and it is not burning rich, you can adjust the idle screw and nothing happens. I think there is something wrong with the carb? I think they still them for this model? I know it was made in 2004 and it is a 31cc, and the only other number I could find was 4mtds0314ra em. Plus the idle screw was the only adj I found unless I missed it somewhere? I thought maybe someone else may of had a problem like this. Also the fuel was fresh too.
 

Mikel1

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If fuel lines and fuel filter are good then most likely it's the carb.
 

gmacmopar

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If fuel lines and fuel filter are good then most likely it's the carb.

The lines look good and I figured if the filter was plugged it wouldn't run very well at all. It has a lot of power on full choke and runs wide open. Also on half choke too! Just when you move the choke lever to run it dies and I checked the plug and you would think it would be running rich on full choke but it is not or doesn't seem to turn the plug black. So it must be in the carb I guess.
 

bertsmobile1

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You need an air fuel ratio of around 13:1 for the mower to run.
The needles & jets control the fuel side the choke controls the air side.
So if you need less air then either you do not have enough fuel ( dirty carb, blocked filter etc etc ) or after the fuel has been mixed with the air , more air is getting in leaking butterfly (carb, leaking manifold, gasket etc etc )

Water tends to build up in the bottom of the carb so while most of the fuel is being drawn from the lile circuit it will run but as you start sucking fuel from the bottom you get water being sucked into the carb and unfortunately they don't run well on water.
 

gmacmopar

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You need an air fuel ratio of around 13:1 for the mower to run.
The needles & jets control the fuel side the choke controls the air side.
So if you need less air then either you do not have enough fuel ( dirty carb, blocked filter etc etc ) or after the fuel has been mixed with the air , more air is getting in leaking butterfly (carb, leaking manifold, gasket etc etc )

Water tends to build up in the bottom of the carb so while most of the fuel is being drawn from the lile circuit it will run but as you start sucking fuel from the bottom you get water being sucked into the carb and unfortunately they don't run well on water.

Well holding off on ordering a new carb took your advice and carefully took the carb apart. I saw that there was a chunk of something blocking half of the filter screen. so took it all apart carefully and blew air in and out of all the small orifices I could see. I am going to put it back on the tiller and see what happens. If it still doesn't run I found the carb I think at Jack's small engine parts.

Thanks for your help
Gary Mac
 

gmacmopar

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Ok guys and gals, I took the old carb apart very carefully and lo and behold there was a big chunk of crap on the screen. I cleaned and blew as best as I could and put it all back together. It finally started but didn't run long. I pulled the plug and it was flooded so I cleaned it and then checked for spark. Now explain and help me I could only get it to spark once (when grounded to the metal outside housing. But as I messed with it I noticed every time O move the choke either from full to half to run I would get a spark but only once? I went and bought a new plug and it did the same thing. Now how in the world can a metal choke lever have anything with the spark? I realize there is a compression stroke which has spark and a exhaust stroke which doesn't but as fast as that piston is moving up and down when you pull the rope you should get more than 1 spark shouldn't you?
Well I went ahead and ordered a new carb and as I messed with it the fuel lines kept splitting so it comes with new ones and then I will try it again. But I welcome everyone's thoughts.

Thanks Gary Mac
 
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