Carburetor problem

Westmoor63

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Hello,
I am working on a Craftsman 6hp B/S lawnmower #122K02 0577. It will start on either, but only runs for a few seconds. The mower sat in a shed unused for about 2 years. I replaced the old fuel, and put a rebuild kit in the carb. I have sprayed aerosol brake cleaner and air from a compressor in all the carb. orifices. All of the passages seem to be open. The fuel bowl has fuel in it, both times I disassembled the carb. The second time I disassembled the carb, I removed the welch plug and cleaned out that passage also.
I am out of ideas.
Any suggestions appreciated.

Ken
 

Westmoor63

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StarTech,
I thought I cleaned the nut. But evidently spraying the aerosol did not do what was needed. I just used a soft copper wire, about the diameter of a horse hair. I did not see what the culprit was, but perhaps old eyes did not help.
I had to give a shot of either and it continued to run, though a little unevenly until I put the air filter assembly back on.
Seems good now.
Thank you many times,
Ken
 

sgkent

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Drained the tank and used all new fuel? Use Berryman's B12 carb and choke cleaner as a starter fluid or gasoline in a squirt bottle. Do not use Ether or it may blow the head gasket or worse. When I pull up that engine it shows an autochoke and primer bulb. Did you check the auto choke to be sure it is closing, and use the primer bulb?
 

Tiger Small Engine

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Hello,
I am working on a Craftsman 6hp B/S lawnmower #122K02 0577. It will start on either, but only runs for a few seconds. The mower sat in a shed unused for about 2 years. I replaced the old fuel, and put a rebuild kit in the carb. I have sprayed aerosol brake cleaner and air from a compressor in all the carb. orifices. All of the passages seem to be open. The fuel bowl has fuel in it, both times I disassembled the carb. The second time I disassembled the carb, I removed the welch plug and cleaned out that passage also.
I am out of ideas.
Any suggestions appreciated.

Ken
Remember, there is no need to remove Welch plug in carburetor. Use a tiny wire and carburetor cleaner and compressor blow gun, and 95% plus of the time it will be good.
 

Westmoor63

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StarTech, SGKent, and TigerSmall Engine,
I learned a lot from your advice. The Berryman sounds better than either. Leaving the welch plug alone is helpful. I will pay more attention to the fuel bowl nut next time.
Thank you for all the advice.
Ken
 

Westmoor63

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Tiger Small Engine, sgkent, and Star Tech,
Berryman is a good idea, leaving the welch plug alone is good advice, and I will pay more care in cleaning the fuel bowl nut next time.
Thank you for your time and great advice.
Ken
 

oldntired55

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Jun 17, 2023
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Hello,
I am working on a Craftsman 6hp B/S lawnmower #122K02 0577. It will start on either, but only runs for a few seconds. The mower sat in a shed unused for about 2 years. I replaced the old fuel, and put a rebuild kit in the carb. I have sprayed aerosol brake cleaner and air from a compressor in all the carb. orifices. All of the passages seem to be open. The fuel bowl has fuel in it, both times I disassembled the carb. The second time I disassembled the carb, I removed the welch plug and cleaned out that passage also.
I am out of ideas.
Any suggestions appreciated.

Ken
if it has an automatic choke... be certain the linkage is not binding, it should be closed when cold. i had one with a weak choke thermo spring, also had one binding on the pivot shaft.
 

thethirstymoose

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Hello,
I am working on a Craftsman 6hp B/S lawnmower #122K02 0577. It will start on either, but only runs for a few seconds. The mower sat in a shed unused for about 2 years. I replaced the old fuel, and put a rebuild kit in the carb. I have sprayed aerosol brake cleaner and air from a compressor in all the carb. orifices. All of the passages seem to be open. The fuel bowl has fuel in it, both times I disassembled the carb. The second time I disassembled the carb, I removed the welch plug and cleaned out that passage also.
I am out of ideas.
Any suggestions appreciated.

Ken
Replace the carb..cheap and simple solution
 

g-man57

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I have an older Weedeater mower with a 4.5hp Tecumseh. I know, I know, really old school - but it has an aluminum deck - light as a feather. Just great for trimming.

I had a similar problem. My mower would start on either and run okay. But without the either, after priming it would start, run a couple of revs and die. I found that by continuing to press the primer bulb that the mower would continue to run. So close examination of the bulb showed a crack in it. I replaced the bulb and it starts/runs just great now. It was sucking air.

Your problem is different than mine was. But it is similar. You said yours will start but die on either. I'll bet there's a hole or crack in the primer bulb. Won't take long to find out. Good luck.
 
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