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Jon K.
Jon K., Small Engine Diagnostic Expert
Category: Small Engine
Satisfied Customers: 5818
Experience:  Gold certified Stihl tech, Service Manager for a rental/repair shop.Certified in most small engines
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engine revs up and down, put fresh gas, in replaced oil, plug,

This answer was rated:

engine revs up and down, put fresh gas, in replaced oil, plug, air and fuel filter, cleaned carburetor with spray

You need to clean and rebuild your carburetor. Before you remove it make sure you diagram all the linkages, pictures help too. REmove and completely disassemble the carb and allow it to soak in a commercial carb cleaner for at least 24 hours. Remove it and dry it with compressed air. It is now clean and can you can reassemble it with a new carb kit. Do not skip anything or you may find yourself doing this all over again.

Customer: replied 7 years ago.
thanks Jon K. will you tell me if the task is doable job by one that has never done it? scale of difficulty? buy kit from John deere or any? What does it include?

Yes it is doable by someone that has never done it before. It all depends on your mechanical aptitude. If you are comfortable working on it then I say go for it, The worst that would happen is that you bring the carb into a shop and have them reassemble it for you. (Usually very inexpensive compared to bringing the whole tractor in to have the carb rebuilt) Scale of difficulty is about a 6 -7 on a scale of 1-10. You should be able to buy it from anyone that sells parts for your engine (the engine is not John Deere)

If you can get me the make model and serial number from the engine I may be able to find you a step by step guide on line for your rebuild and after reading that you can decide if you want to dive into this.

Edited by Jon K on 8/26/2010 at 1:28 AM EST
Customer: replied 7 years ago.
I will do it . Do you think old & stale gas is to blame? or gas additive after the season? It is Kohler 17 HP. I will get the info tomorrow as it is dark now. I would like to accept the Answer and click it but would I lose contact ? how do I get hold of you later? By the way, I see your pic, don't know you, buy I feel you offer a great service and hope you're this generous in every aspect in your life. I hope there is something in it for you after all the time I have taken. Sincerely, Mike

You can always come back to this question when you log in. Thank you very much for the kind words.

Old or stale gas is the number one reason carburetors get clogged up these days. With the addition of ethanol in todays fuel you only have about a 2-3 month shelf life with it before it starts to go bad. Gas additives like Stabil only add about a month or two to the life of the fuel. I always advise my customers to drain the fuel out of their engines and then try to start them until they just turn over and don't even try to start when they put the machine away for the winter (or summer) and then start with fresh fuel at the beginning of the season.

I have a few sites that show the rebuilding process of Kohler carburetors, so when you get a chance to get me the model and spec info off yours I will get you the appropriate one for you to follow along during your rebuild.

Jon K. and other Small Engine Specialists are ready to help you
Customer: replied 7 years ago.
Hi Jon K. ! I have a Kohler Command 17.5 spec no. PS-27509 2KHXS-4902GB 490 CC Model# XXXXX spec 27509

Hi Mike, This one almost got me. Your model number is XXXXX not 419. No big deal I figured it out.

The kit you need is Kohler part number 12 757 03-S and should cost you just under $10


Here is the link to the site I was telling you about, I think it will help you out quite a bit.