Kohler 24 surge at low idle

PTmowerMech

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Kohler 24hp
M# KT735-3012

I'm guessing it's gonna have to be cleaned out thoroughly. The gas was from last fall. Some small bits of something in the carb. bowl. Bout the size of the end of a pen or smaller. After draining all the fuel, adding new non ethanol and running it for about 20 or 30 minutes, it ran better than before.
New plugs, oil, fuel and air filter. Removed the bowl & needle. Then sprayed a couple of squirts of carb cleaner in the fuel inlet, then back the other way. Then the same with the sea foam spray (top engine cleaner and lube) Then up the main nozzle.
Put all that back together and still getting a surge at low idle and a little backfire through the carb. The choke plate is coated black.

Question is, should I let this engine run longer with the fresh fuel in? Or just bite the bullet and take it off and clean it out.
 

Rivets

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Are you a PTmowerMechanic or a cheap armadillo? Bite the bullet or follow this mechanics proverb. “Never time to do it right, always time to do it over”.
 

PTmowerMech

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Are you a PTmowerMechanic or a cheap armadillo? Bite the bullet or follow this mechanics proverb. “Never time to do it right, always time to do it over”.

LMAO......I knew someone was going to tell what I've been telling myself for any hour.

I could've done had it off, cleaned and back on. :rolleyes:
 

PTmowerMech

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@bertsmobile1. I tried that thing you said about the dishwashing pods in the ultrasonic... And I didn't really see any improvement. This one was coated black through the venturi. I set it at 30 minute intervals. Had to do it three times, and could still see spots.
I may go back to the dawn dish soap.

What did you say you used?
 

bertsmobile1

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Now that you have a stens account you can try Stens Ultrasonic cleaning solution
The price on their ultrasonic cleaner is pretty good too for a big unit .
I use a similar solution from another supplier at 1/2 strength.
If you are getting a grey deposit on your carbs that is because you are not pulling them out while the cleaner is still running.
Some where on the bottle there should be a warning not to soak in the solution .
This is because the solution is very caustic with a pH usually above 12.
Base metals , Zinc , Aluminium, Magnesium , Bismuth , Antimony etc will all dissolve in a caustic solution and the dissolution product is what is getting stuck on the outside.
I set the cleaner for 30 minutes then my phone timer for 25 so I can pull them out while it machine is running then dunk them direct into the vinegar to neutralize the caustic solution.

Lots of vary handy tools in the catalogue but forget the cube carb ones as EPA regulations prevent them selling the ones you need to you.
But you can buy them all of ebay or amazon

The dishwashing tablets were for the pre-ultrasound days when I would have a big pot on the BBQ at a rolling boil and pop the carbs into into it.
 
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bertsmobile1

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lol.. Is that what you use? Or is that information top secret?
Similar stuff from a different supplier Gripskie & Sons
We have a 10 gallon ultrasound which we made from a kit in the top shed and that one uses Kerosene .
We put real tractor parts in that one, complete motorcycle engines etc.
I was going to make a couple more of them but found for external cleaning the soda blaster was a lot cheaper & quicker.
Right now I am still using the animal feed soda ( which is finner & softer than blasting grade but it was $ 12 for a 25 kg bag 2 years ago & I still have not used it all yet.
Good thing about soda is it dissolves in cold water .
The gun is just an air duster with a hole in the outlet for the soda to go in and a pop bottle over the hole.

I have tried a lot of things for cleaning as it takes a long time and is not something you can bill out for fully.
Truck wash worked really well but was very caustic & even wen diluted to 100:1 burned my hands but it dd rip the crud off really quickly.
Tried it a 200:1 in the ultrasound but all the parts came out heavily oxadized with a very tough coating.

Brand names & formulas differ state to state & country to country .
 

StarTech

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Hmmm, I use a 12.5 pH non-residual soap in my USC without having pull the carburetors while the USC is running. Usually I get them out within an hour but I have left them sitting in the solution overnight. I do run a short cycle the next day if I do. Note that not all soaps are compatible with the aluminum, plastics, and rubber parts. But I now I am only using 2 Tbsp per 10L too. I also use Dawn Platinum at the same strength which is like using 4 Tbsp of Dawn Ultra but I only do that on extremely dirty carburetor exteriors.
 
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