Kohler tune up

[Horse46 512]

I have recently acquired a 16hp Kolher, I have got it running however it won't run at low revs. It is sweet at high revs but when I close the throttle down past half way it just cuts out.

Any suggestions?

[rmaynard 14,865]

I would do a total carburetor cleaning first. And remember, idle on that engine is around 1100 RPMs

[Horse46 512]

Cheers buddy i will start with that 

[Fordiesel69 206]

Locate the screw on the carb that is at an angle, not the one directly on top.  Turn this to adjust idle mixture.  That is after you clean the carb.  I personally reommend the Berrymans Chem dip.  It is not what it used to be due to the VOC's being reduced but it still works well.  Also see if there is play in the throttle shaft.  A loose, worn throttle shaft will not allow for proper idle mixture setting.  You can adjust all day and not get it right.

[Horse46 512]

As I've already said I have recently purchased another   a C series with a big ole 16hp motor!

It's not in the best shape, but the motor does run, albeit only at high ish revs at the moment, no smoke or rattles though so I'm confident it will be ok.

It has had a very bad re paint at some point, and it has a dent or two. Someone has welded the hub to the axle, so I guessing the keyway is battered? All the tie rods track rods or whatever there called have a ton of play in them, and thats only on first inspection.

As my C-101 is in pretty good shape, I'm hatching a plan to swap the motors, or at least releive the 161 of its for now.

I felt that the 10hp isn't quite up to my 42inch deck.

Should this be a straight forward swap?

They look the same, apart from the 16hp being a bit bigger. The sump is the same, they are both shaker mounted.

Is there anything I need to be aware of?

[pacer 3,159]

That should be pretty straight forward ... I just finished a triple swap on a C frame, it had a B&S in a shaker mount that was trashed, I pulled it and stuck a K241 flat mount in it with no problems, then like you I came on a K341 (love those big boys!) and pulled the 242 and mounted the 341 back into it with a shaker mount - the B&S shaker mount would not fit to the 341, but it had came with the mount and it bolted up no problem.

[Horse46 512]

Thanks Pacer, I was hoping it would be a simple swap, but it isn't always that simple sometimes, so I thought I ought to ask before I started, I don't like nasty surprises.

[Horse46 512]

Ok the story so far 
I've cleaned the carb and changed the main jet, one that my neighbour gave to me but I think it's from a 12hp

i there a difference because with it screwed all the way in it still runs. 

Does  the 16hp have a longer needle?
 

[rmaynard 14,865]

The K341 uses a different needle. 

[Horse46 512]

What sort of movement in the throttle shaft indicates wear?
I have some movement in my other carb andt that runs fine. 

[Wheel-N-It 2,967]

If you can move the throttle shaft around in the carburetor while the engine is not running then the throttle shaft bushing needs replacing. Most of the K341's have worn bushings so you are not the only one. The more that area is worn, the less you will be able to tune your carb.

[Horse46 512]

I spent this afternoon cleaning the carb and re fitted the original needle, I also noticed that the throttle assembly up to the governor was not the same as my C-101, so I made them the same.
This is where I'm at. The motor starts with a little bit of throttle and choke only for a second or two, it ticks over, and it revs up freely, and back down to tick over fairly normally.
I left in run for about five minutes to get it warm so I could make adjustments. 
All went fine, the problem now is it won't start when it's warm.

Any ideas?

[Aldon 4,826]

I doubt my experience will help you specifically but might help someone in future if they are searching forum for fuel related issues.

I picked up a 16hp Kohler horse last year. I had issues with it as well. Changed everything imaginable including fuel lines. 

I needed to prime directly to get it started and could get it to run better at full throttle but not great and it would cut out.

i finally located the root cause for poor running.
the Fuel shut off valve had become approximately 85-90 percent clogged from the many years sediment. 

I pulled it apart, cleaned it out real well, replaced the small O-ring and reinstalled. The 16hp runs excellent now.

 

[Wheel-N-It 2,967]

Remove the air cleaner and do this;
When warm try the same procedure using a little bit of choke and throttle. If the engine then starts, your low speed adjuster need to be opened a tad to give the engine more fuel at idle.  A tad = 1/4 of a turn to the left. If that helps but the problem still somewhat exist then turn it 1/8th more. Tuning a carb is fun but it takes practice.  Its important for you to read what I have written next;
I know this is not fuel related. But alot of little problems with the old engines are electrical in nature. Replace the spark plug, and the points and condensor. Get your ignition system up to speed in order to ignite the fuel properly. Make sure you have a good spark plug wire from the coil to the plug. Make sure all the wires and connections from the ignition switch forward are clean and tight.

[Horse46 512]

I doubt my experience will help you specifically but might help someone in future if they are searching forum for fuel related issues.

I picked up a 16hp Kohler horse last year. I had issues with it as well. Changed everything imaginable including fuel lines. 

I needed to prime directly to get it started and could get it to run better at full throttle but not great and it would cut out.

i finally located the root cause for poor running.
the Fuel shut off valve had become approximately 85-90 percent clogged from the many years sediment. 

I pulled it apart, cleaned it out real well, replaced the small O-ring and reinstalled. The 16hp runs excellent now.

 

Aldon, thats a good call, however my fuel shut off is leaking, so I'm running from a petrol/gas can.

Remove the air cleaner and do this;
When warm try the same procedure using a little bit of choke and throttle. If the engine then starts, your low speed adjuster need to be opened a tad to give the engine more fuel at idle.  A tad = 1/4 of a turn to the left. If that helps but the problem still somewhat exist then turn it 1/8th more. Tuning a carb is fun but it takes practice.  Its important for you to read what I have written next;
I know this is not fuel related. But alot of little problems with the old engines are electrical in nature. Replace the spark plug, and the points and condensor. Get your ignition system up to speed in order to ignite the fuel properly. Make sure you have a good spark plug wire from the coil to the plug. Make sure all the wires and connections from the ignition switch forward are clean and tight.

My plan was to try n tweak the carb to get it running as best I could, but this problem kinda put it on hold. 
I will order some new sparking bits and try again with the filter off, I will also try to up load a vid of it running.

[Horse46 512]

I don't want to start a new thread for this so I'll ask away.
On the engine cover the sticker has a spec no. that starts with EX anyone know what thats for, I know what the rest refer to?

[Horse46 512]

I was chatting to a mechanic friend of mine, and relating the story of the hard starting when the motor is warm, He said check the valve clearance as he had come across valves that were to tight, made for hard starting as they closed up when the engine is warm.
Sounds logical, anyone else hear of this?

[Wheel-N-It 2,967]

That is possible although I've never experienced that problem with one of my Kohlers. I have had that problem with a few honda motorcycle engines.

[oldredrider 2,547]

If we go back to the 70's when these engines were built, a "tune up" included a check and adjustment of the valves. Cars, trucks and small engines all needed their valves adjusted from time to time.
I have chased down the obvious fuel/fire issues without success until nothing was left to check but valve clearance. ..Readjust valves and the engines run fine.
A lot of people will tear a carb apart for cleaning and inspection but dont bother to check valve clearance while carb is off and breather cover is easily accessable.

When was the last time you check valve clearance? 

[Horse46 512]

Oldrider that makes a lot of sense, as I've only bought this one the other week I've not checked them yet, however I will and report back if it cures the issue.

I will also check them on my 10hp as well, but that one runs fine.