# carb problem!!!



## critter91 (Feb 27, 2008)

i can get my riding mower to start now but can't rev it up or keep it to run for more than a few minutes. replaced all fuel lines. help!


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## glenjudy (Aug 26, 2006)

Critter, try not to start new threads for questions regarding the same problem for the same equipment. Just 'Post Reply' to continue.
Is this the same Briggs twin model number is 400707. type is 0111. on a Craftsman mower.?
Does it have a new fuel filter ?


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## critter91 (Feb 27, 2008)

yah. i can keep it running if i adjust the choke alot. think it could be the gas cap?


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## glenjudy (Aug 26, 2006)

Could be gas cap, but if it was, choking probably wouldn't help.
Did you mention in other threads if you had cleaned and rebuilt the carb ??
How long has it been, as far as you know, since it ran pretty good ?
thanks,


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## critter91 (Feb 27, 2008)

i just had bought the carburetor. didn't clean it or rebuild it. when i installed it the engine fired right up and ran good but i couldn't rev the engine up without it dying. think i need a carb rebuild kit?


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## glenjudy (Aug 26, 2006)

Did you buy new carb complete with the fuel pump?? or did you move the pump from the old one to the new one?
Are the plugs wet or dry after it dies when attempting to rev up??
Another thing to check is to see if coil is producing spark immediately after it dies, an in-line spark tester would be helpful here, but can remove plug reattach to wire and ground to head while turning engine.


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## critter91 (Feb 27, 2008)

i buoght it complete with the fuel pump. seems like every time i sit on the seat it starts acting weird.


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## pyro_maniac69 (Aug 12, 2007)

400707 is an opposing twin isn't it?

If so, your going to have to adjust the carb so that it will let your motor get the gas it needs to run. Not every engine is the same, even with a new carb, some fine adjusting will be needed


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## bgbass (Jan 11, 2008)

You say when you sit on seat it acts wierd. check under seat to see if your grounding out a wire


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## glenjudy (Aug 26, 2006)

critter91 said:


> .....i can keep it running if i adjust the choke alot. think it could be the gas cap?





critter91 said:


> ............ seems like every time i sit on the seat it starts acting weird.


hhmmm...the plot thickens..
btw, the idle jet just under the fuel pump should be turned out 1 1/2 turns from being lightly seated.
Are you on the seat when you get the engine running ??
Describe 'acting weird'..'acting weird' doesn't give us a lot to go on.
thanks,


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## critter91 (Feb 27, 2008)

yes the engine is running when i sit on it. its like i can get it to idle nicely for about 10 minutes but then when i sit on it it wants to die. also when i put it in gear it has almost no power. do you think i need to clean the jet?


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## bgbass (Jan 11, 2008)

It sounds like when you sit on the seat your pinching a wire and grounding it out


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## critter91 (Feb 27, 2008)

no i checked under the seat and the mower and there are no wires hooked up. i checked the spark plugs after it died and they were dry. does that mean its not getting enough fuel? would putting an air filter on it help at all?


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## glenjudy (Aug 26, 2006)

Does it throttle-up somewhat normally?


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## critter91 (Feb 27, 2008)

if i open up the throttle very slowly it revs a little bit. but after it runs for about a minute or two you can't rev it at all without it dieing. then after a couple more minutes of idling it dies.


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## glenjudy (Aug 26, 2006)

Is the carb you bought brand spanking new, or just a different one ?


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## critter91 (Feb 27, 2008)

i bought it used. yesterday i put a different carb from a different tractor on it. they both had the same engines and the engine ran great. so i think the carb is just dirty. how do i clean the insides? i have already taken the whole thing apart and sprayed carb cleaner in those little holes but it still doesn't run right. only on choke now i can rev it up.


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## glenjudy (Aug 26, 2006)

Would be better if you used a carb dip, like Gunk, etc., for several hours for the carb proper, not the fuel pump. Use carb cleaner spray to further clean out the main jet, which is behind the bowl drain nut, and all other orifices/passages, then blow clean with compressed air. Your best bet is to buy the rebuild kit for both the carb and the fuel pump.
Let us know.


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## critter91 (Feb 27, 2008)

i got my carb in some carb dip and am going to take it out in 24 hours. i found out that a little tiny hole is preventing gas from getting enough into the intake. i took some compressed air and it starts up every time now but still runs a little rough. thanks for the advice glenjudy.


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