Kohler Courage 26HP Running Issue

[Zeek 2,286]

I bought a tractor with a Kohler Courage 26 HP twin. It had not been running for about three-four years. It has 352 hours on it.

I did the following:

• Drained the fuel tank and lines and flushed them (smelled like varnish)
• Replaced fuel filter
• Removed carb and cleaned it
• Replaced air filter
• Cleaned plugs
• Lubed cables

It fired up after a few cranks, ran good no smoke. After about 3 minutes, it started doing a high/low RPM fluctuation, then quit. Restarted a few minutes later...same thing.

 

1. What could be causing this?
2. There is a random disconnected plug near the carb that I cannot find the male end to (pics). Black goes into manifold harness. . .?
3. What is the device with a wire at the bottom of the carb bowl?

 

Thanks for any advice!

 

[gwest_ca-(File Mod) 11,043]

Fuel shut off valve or solenoid?

 

 

[Shynon 7,459]

That the solenoid that shuts off the fuel. 

[Zeek 2,286]

I'll look at the service manual for the wire issue. The speed fluctuation is similar to an issue I had with and old Toro snow blower, so I'm thinking it's related to the carb.

[Shynon 7,459]

You can pull the solenoid magnet out and run without it. You just won't have any fuel shut off.

[Zeek 2,286]

9 minutes ago, Shynon said:

You can pull the solenoid magnet out and run without it. You just won't have any fuel shut off.

 

When you say that do you mean the part attached to the bottom of the carb? And could that be causing the erratic idle and stall? This is my first time messing with this style engine.

Edited June 18, 2021 by Zeek

[Shynon 7,459]

Yes, inside there is a magnet that opens and closes the fuel. If you remove

 the magnet it will not shut off the fuel. Try it and see if it runs better. If you need a new solenoid $$$$$$

[Zeek 2,286]

13 minutes ago, Shynon said:

Yes, inside there is a magnet that opens and closes the fuel. If you remove

 the magnet it will not shut off the fuel. Try it and see if it runs better. If you need a new solenoid $$$$$$

 

Thanks, I'll try that. I see I can get a whole carb online for $30 or a solenoid on fleabay for $12. Nowadays if I have carb issues (Stihl equipment) I have been throwing them in the garbage and replacing instead of screwing with them. This tractor though I'd just like to flip and get rid of once it's running correctly. Some idiot messed with it before I got it and may have messed something up with the wiring.

[gwest_ca-(File Mod) 11,043]

If you supply 12 volts to the solenoid you should hear and feel it activate. Since you suspect wiring problems try feeding it a good 12 volt source to see if it eliminates the problem.

 

Garry

[lynnmor 7,306]

That fuel shut off in the carb bottom helps to prevent a backfire when shutting down.

[Handy Don 12,230]

4 hours ago, lynnmor said:

That fuel shut off in the carb bottom helps to prevent a backfire when shutting down.

Its main purpose, by cutting off the fuel, is to eliminate the pollution from unburned fuel pushing through the engine once the spark is stopped but the engine is still turning. The "anti-backfire" is an incidental benefit!

If it's like others I've seen, the solenoid operates a needle valve which is just as vulnerable to dirt/clogging as any other valve in the carb.

[Zeek 2,286]

Problem solved! After three carb cleanings and the same problem, I threw the carb in the trash. I got a new one Amazon for $30. I put it on and nothing else except connect it (no adjustments). It fired right up after a few cranks and purrs like a kitten!!

 

Garbage carb - yes I put 12V to the solenoid and that was fine.

 

New carb installed

Edited June 25, 2021 by Zeek