Craftsman/MTD 12A-A1BA729 knock that went away


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Old 05-04-21, 04:21 PM
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Craftsman/MTD 12A-A1BA729 knock that went away

In one of my previous threads, I posted about the mower that's in the subject of this thread. Got the replacement blade adapter today and put it on, started the mower, and it had a knock. I shut the mower off, flipped it back onto its side(gas over oil), and checked to make sure I had everything tight, and that the blade wasn't on wonky and hitting the deck. Found nothing hitting, or off kilter, flipped it back onto its wheels, started it back up, and the knock was still there. I assumed at this point it was an engine knock. Figured "what the heck, it's going to probably die anyway" and went and mowed between our fence and the neighbors house in some really dense thick weeds. As soon as I got into the weeds and bogged the engine down, the knock went away. Engine ran fine after that. An engine knock doesn't just randomly go away from my personal experience. Anyone have any ideas as to what may have been the sound of the noise?
 

Last edited by crazycory22; 05-04-21 at 04:22 PM. Reason: Changed title a little bit
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Old 05-04-21, 06:34 PM
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That type of thing is usually coming from outside the engine -Blade, engine mounts - something like that. If there was no knock before the work and a knock after it's probably connected with the work done.
 
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Old 05-05-21, 07:58 AM
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The blade bolt is bottoming out leaving the blade loose try adding a thick washer under the bolt. That is probably why the first adapter got destroyed. Have a good one. Geo
 
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Old 05-05-21, 11:19 AM
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Or when you tipped the mower and got it back up right the oil didn't make it back to the lifter and caused the knock and when the oil made it back to the lifter the knock stopped.
 
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Old 05-05-21, 11:33 AM
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I agree with checking the blade adapter again, adding the washer. Especially given the past information on this mower, that's your problem area.
 
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Old 05-05-21, 05:07 PM
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I will go get a washer and add it under the bolt. I'm assuming that it would go between the bolt and the blade hold down?
 
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Old 05-06-21, 11:26 PM
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There should already be a washer there. I would put it between the bolt head and the existing washer.
 
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Old 05-08-21, 04:08 AM
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There isn't a washer, nor was there ever a washer. Just what's in this link ----->Bell Blade Support.
 
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Old 05-08-21, 08:21 AM
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There should have been a washer on the bolt if there wasn't it would further indicate the cause for the damaged adaptor. Have a good one. Geo
 
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Old 05-08-21, 10:56 AM
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That part is basically the washer. Put a lock washer between the head of the bolt and that part you linked to.
 
 

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