123 running issue

Teamroper · #1 03-26-2016, 09:13 PM

Hello folks been checking the sight out and have gotten lots of info. However I have an issue and I am sure the answer is with in these pages.

I have aqquired my first cub cadet it's a 123 in not the best of condition. I rebuilt the carb and the motor kinda runs. The issue I am having is I have to partially cover the carb with my hand to keep it running getting way to much air to gas ratio. I either don't have it set correctly or something else that I'm over looking.
Top screw 2 1/2 turns. Low speed 2 turns and 1 1/4 on the other screw.
What have I done wrong need some answers please

Thanks
Tim

Jeff in Pa · #2 03-26-2016, 09:21 PM

First, welcome to OCC

You mention "rebuilding the carb". Has it been completely disassembled and have you made sure all the passages are clean? Have you made sure the tiny holes in the adjustment screws are clean? Did you use carb cleaner and made sure it came out of the passages ? Did you get a Kohler carb kit? Is there slop in the shaft for the choke? ( does the shaft wobble in the carb bores ? )

Jeff

Teamroper · #3 03-26-2016, 09:40 PM

Yes, Kohler kit was used. All holes clean, and let carb soak over night in a bucket of cleaner. Yes, there is some play in the bushing.

Jeff in Pa · #4 03-26-2016, 09:51 PM

Did you use an aerosol can of cleaner with the tube to make sure the passages were clear?

I'll let somebody else post suggested starting points for the carb.

budscub · #5 03-27-2016, 07:33 AM

Along with cleaning the carb, make sure you have a good strong flow of fuel from the fuel line, before the it enters the carburetor. In having to partially block the throat, (basically running partially choked,) that indicates the starving for fuel. When you partially choke a carburetor, this creates more vacuum across the main jet an cases it to pull more fuel from the float bowl.
Now, with that said, as others have pointed out, this is why all the holes in the main jet tube must be clear.
I would double check the float level setting, and confirm good fuel flow to the carburetor.

ol'George · #6 03-27-2016, 08:14 AM

Quote:

Originally Posted by budscub

Along with cleaning the carb, make sure you have a good strong flow of fuel from the fuel line, before the it enters the carburetor. In having to partially block the throat, (basically running partially choked,) that indicates the starving for fuel. When you partially choke a carburetor, this creates more vacuum across the main jet an cases it to pull more fuel from the float bowl.
Now, with that said, as others have pointed out, this is why all the holes in the main jet tube must be clear.
I would double check the float level setting, and confirm good fuel flow to the carburetor.

Buds cub is spot on.
Try unscrewing the main jet on top,(easiest thing to do) and checking with a "tag wire" all the drilled holes and blow them out good with air--AGAIN.
"Tag wire" is the fine wire that attaches identification or instruction tags to things. it is fine wire,--- sometimes I carefully use a welding tip cleaner.
There is a passage in the center of main jet between the crossways holes on some. those have to be clear also.
reinstall and try it. let us know.
The worn throttle shaft should not cause the problem you describe.
You can go a 1/2 turn more on the initial setting on the main jet to try it.

ironman · #7 03-29-2016, 07:24 AM

Quote:

Originally Posted by Teamroper

Hello folks been checking the sight out and have gotten lots of info. However I have an issue and I am sure the answer is with in these pages.

I have aqquired my first cub cadet it's a 123 in not the best of condition. I rebuilt the carb and the motor kinda runs. The issue I am having is I have to partially cover the carb with my hand to keep it running getting way to much air to gas ratio. I either don't have it set correctly or something else that I'm over looking.
Top screw 2 1/2 turns. Low speed 2 turns and 1 1/4 on the other screw.
What have I done wrong need some answers please

Thanks
Tim

Tim, the "other screw", as you refer to it, does not get a specific setting. It is merely a mechanical stop to keep the carb's throttle open enough for the engine to keep running at idle. If the screw is turned in to far the engine will race, if it's not in far enough the engine will die. Use it to fine tune your idle speed after the high and low speed mixtures have been adjusted. (and your timing is correctly set)

Teamroper · #8 03-30-2016, 06:58 AM

got the ole girl running pretty good. When I say a heavy spring the govenor arm could not move heavy enough to close the screen door type..
The tractor came with a homemade blade on it needs some mod to work properly.. I was really suprised with the power the 123 has I used it to grade my drive way yesterday all I can say is that it really impressed me.
thanks
Tim

J-Mech · #9 03-30-2016, 11:48 AM

Better make sure the governor has the right spring on it. You say you removed it..... you did leave a spring on it though right?? IT HAS TO HAVE A SPRING. Better adjust the governor and make sure the high-idle, no-load is set right. Should be 3600 RPM... up to 3800 is acceptable.

Teamroper · #10 03-31-2016, 06:37 AM

Yep has the correct spring on it now have an older gentelman that all he has ever done is work on small engines and he helped me with the correct spring. engine is purring now. Few more things to fix up on the machine and then strip it all down and give it a new paint job. Wires are in poor condition from setting out side for a large part of it life.