Craftsman LT 4000 engine dies

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Regwal

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I have 4000LT with a peculiar problem. It starts and runs perfectly, for ever and ever; that is until I disengage the mower blades. Then engine dies like fuel has been shut off. It will restart but then dies again and won't restart until it sits for a bit. I purchased this mower for an extra mower to keep at another house rather than trailer one there often. I'm thinking the PO had this problem and decided to sell because he couldn't figure problem out. Well I haven't either. I'm sure something is going on with carburetor but haven't had time to troubleshoot. Just wondering if someone has any idea what is causing this? When engine starts to die if blades are re-engaged, the engine catches back up. There is no lag either when blades are disengaged, starts dying immediately. I'm baffled, to say the least. :confused:
 
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shiftsuper175607

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Regwal said:
I have 4000LT with a peculiar problem. It starts and runs perfectly, for ever and ever; that is until I disengage the mower blades. Then engine dies like fuel has been shut off. It will restart but then dies again and won't restart until it sits for a bit. I purchased this mower for an extra mower to keep at another house rather than trailer one there often. I'm thinking the PO had this problem and decided to sell because he couldn't figure problem out. Well I haven't either. I'm sure something is going on with carburetor but haven't had time to troubleshoot. Just wondering if someone has any idea what is causing this? When engine starts to die if blades are re-engaged, the engine catches back up. There is no lag either when blades are disengaged, starts dying immediately. I'm baffled, to say the least. :confused:
Click to expand...

check the seat switch
If is it always when the blades are engaged it is a safety switch/wiring problem



Also...you did not share enough info..
is that a Chevy or a Ford engine?
 
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Regwal

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Also...you did not share enough info..
is that a Chevy or a Ford engine?[/QUOTE]

Jumped the safety switch so ruled that out. It happens when blades are dis-engaged, not when they are engaged. Runs fine after sitting for about 10 minutes. Engine is B&S 22hp. Thankfully I mow almost an acre without having to dis-engage the blades.
 
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bertsmobile1

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As it happens when the blades are dissengaged sounds like a kill relay or the PTO switch itself.
Something is grounding the kill wire.
Because of all the idiot morons advocating the bypassing of seat switches cause they are too fat to get their hands on the parking brake, mower companies are making safety circuits more & more complicated
Your mower should have a kill relay and either the kill relay is faulty, the PTO switch is faulty or the wiring between them is shorting out, and remember this can be a Ground short as well as a power short.
 
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Regwal

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bertsmobile1 said:
As it happens when the blades are dissengaged sounds like a kill relay or the PTO switch itself.
Something is grounding the kill wire.
Because of all the idiot morons advocating the bypassing of seat switches cause they are too fat to get their hands on the parking brake, mower companies are making safety circuits more & more complicated
Your mower should have a kill relay and either the kill relay is faulty, the PTO switch is faulty or the wiring between them is shorting out, and remember this can be a Ground short as well as a power short.
Click to expand...

Thanks Bert. I had decided there might be a switch somewhere I missed when doing a quick evaluation. I have got to look again for a switch and go from there, once time permits (and weather). What is puzzling though is after sitting it starts right up. Without sitting, it will start once but dies after about 10 seconds. Then after sitting it starts and runs great. This will repeat.
 
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bertsmobile1

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Well my fall back is an inline spark tester & a can of starter fluid
Install the spark tester then go mow.
This instant it stops , or refuses to start check the spark tester.
No red flashes = electrical problem
Red flashes = fuel problem.
If it starts right up with a shot of carb cleaner that confirms a fuel problem.
 
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