Kohler XT800 can't get it to run

jimigunne

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It would not even fire a bit without spraying starter fluid into the intake. It would rev up for a second and then die. I noticed that the choke butterfly was not closing, so I needed an new automatic choke. When I tried to remove the main jet, the slot had gotten so buggered up that it could no longer be removed, so I ordered a whole new carb. Replaced both the automatic choke assy and the carburetor. However, it behaves exactly the same way as before. I checked to see if the bowl was filling up, and it was. I checked the throttle linkage, and it is opening the throttle up on the carb. How can the carb jets be clogged up from the factory? Any ideas?
 

ILENGINE

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Make sure you have power to the fuel solenoid on the carb in both the start and run key positions. There has been cases where the key switch didn't supply power during certain key positions.
 

primerbulb120

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Make sure you have power to the fuel solenoid on the carb in both the start and run key positions. There has been cases where the key switch didn't supply power during certain key positions.

This is a push mower engine. It does not have a fuel solenoid, and I don't think the XT series came with electric start, so no key switch either.
 

ILENGINE

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This is a push mower engine. It does not have a fuel solenoid, and I don't think the XT series came with electric start, so no key switch either.

Your right, it's been one of those days. After dealing with some of the repairs I have this summer, I am ready for a vacation.
 

jimigunne

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Yea, theres no fuel solenoid. The other possibility of course is the throttle mechanism. But it does appear that when I set it to the start
position (fast) the linkage is opening up the throttle on carb in usual manner. So I am completely baffled. Even though its a brand new carb,
I guess I have no choice but to try cleaning the jets. But I can't believe that the carb is defective from the factory. What are the odds?
 

bertsmobile1

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Take the rocker cover off and check the valve operation ( or lack there of ) .
Poke a pencil or BBQ skewer or drinking straw ( please do not use a hard object like a screwdriver )
Watch for the inlet valve opening just after TDC then doing a little bump just before TDC , both valves closed ( power stroke ) then the exhaust opening on the up stroke and closing just before the inlet opens.
Up & Down are as if the spark plug is pointing up.
 

jimigunne

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Well, it must be sucking in the ether starter fluid into combustion chamber, since it does start and rev up for about 2 seconds before dying.
 

bertsmobile1

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Did you come here for help or an arguement ?
If the lash is too small then the valve opens too late & closes too early.
The air rushing past the emulsion tube has to suck the fuel out of the carb bowl, break it up into droplets then get it into the cylinder to burn.
That takes a lot of energy which comes from the velocity of the air.
valve opens too late and closes too early = not enough suck.
the starter fluid is already atomised by the propellant in the can.

You can easily test the carb by removing it and passing air down the venturi.
High volume low pressure is best ( vacuum cleaner that blows ) air duster blowing through a dunny roll center or just compressed air.
If the carb has a fuel line on it with fuel atomised fuel should blow out of the engine end.
Dirty, messy but can rule the carb in or out of the problem.
Not a good idea to smoke while you are doing it.
 

cambre

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Listen to bertsmobile1. He is the best engine repair man I have ever dealt with. I have done engine repair most of my life & I am 78 yrs. old. I though I knew a lot until I met bertsmobile1. Listen to him, he knows what he is talking about. He has gotten me through several problems.
 
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