Hi All,
Sorry for the long post but I thought I should give a full history. I have a KT745-3001 26HP engine on a 2013 cub cadet tractor. Late last summer it got invaded by mice and the chewed up the engine wiring on the ignition coils. So, I ended up replacing both coils and the engine wiring harness, and I ended up changing the starter since it has a lot of slop in it. I replace them with aftermarket ones, and after re-assembly all seemed good. I winterized it and stored it over the winter.
Now fast forward to this year and this spring I have been trouble shooting an issue where the engine seems to be out of timing, I.E. when turning over it will suddenly seem to want to go backwards, and then seem to back fire through the carb. So I pulled to covers off and sure enough the keyway was sheared. I replaced the key and re-assembled. Engine fired right. I mowed my lawn and it seemed to run a little rough by the time I finished. I shut it off and cleaned it up prior to putting it away, and when I went to start it the same issue I had before seemed to be back. I disassembled, but the key look fine and everything seemed OK. looking things over I discovered the starter shaft was bent, so I figured that was at least part of the issue, so I again purchased a new starter. I had noticed the valve covers were leaking a little so I decided to pull them off and while I was at it I checked the valve clearances. All of them were a bit off (too much clearance) so I adjusted them, and changed the oil and new filter. Reassembled and started it I should great and started with no issues. Started to mow my lawn and about 200ft into it I heard some lout knocking and it began to run rough. Pulled it into the garage and shut it off. Let to cool and tried to start again, and it knocked and banged, but it also had that same out of timing symptom. So disassembled again. Key looked good, pulled valve cover off and the left cylinder (look form the front/carb side) ended up having a bent upper push rod, and the lower push rod had popped off the rocker. I believe this may have happened because of my adjustment and not tightening the locking screw properly (first time I have adjusted rods), but not 100% sure on that.
So now to my questions:
1) can I just replace them bent push rod or am I looking at a more extensive repair. The motor spins free right now (plugs removed)
2) Any thoughts on the cause of this (other than my not tightening the set screw correctly.
3) Any thoughts on the out of time/backfire symptoms?
Thanks a bunch ahead of time!
Sorry for the long post but I thought I should give a full history. I have a KT745-3001 26HP engine on a 2013 cub cadet tractor. Late last summer it got invaded by mice and the chewed up the engine wiring on the ignition coils. So, I ended up replacing both coils and the engine wiring harness, and I ended up changing the starter since it has a lot of slop in it. I replace them with aftermarket ones, and after re-assembly all seemed good. I winterized it and stored it over the winter.
Now fast forward to this year and this spring I have been trouble shooting an issue where the engine seems to be out of timing, I.E. when turning over it will suddenly seem to want to go backwards, and then seem to back fire through the carb. So I pulled to covers off and sure enough the keyway was sheared. I replaced the key and re-assembled. Engine fired right. I mowed my lawn and it seemed to run a little rough by the time I finished. I shut it off and cleaned it up prior to putting it away, and when I went to start it the same issue I had before seemed to be back. I disassembled, but the key look fine and everything seemed OK. looking things over I discovered the starter shaft was bent, so I figured that was at least part of the issue, so I again purchased a new starter. I had noticed the valve covers were leaking a little so I decided to pull them off and while I was at it I checked the valve clearances. All of them were a bit off (too much clearance) so I adjusted them, and changed the oil and new filter. Reassembled and started it I should great and started with no issues. Started to mow my lawn and about 200ft into it I heard some lout knocking and it began to run rough. Pulled it into the garage and shut it off. Let to cool and tried to start again, and it knocked and banged, but it also had that same out of timing symptom. So disassembled again. Key looked good, pulled valve cover off and the left cylinder (look form the front/carb side) ended up having a bent upper push rod, and the lower push rod had popped off the rocker. I believe this may have happened because of my adjustment and not tightening the locking screw properly (first time I have adjusted rods), but not 100% sure on that.
So now to my questions:
1) can I just replace them bent push rod or am I looking at a more extensive repair. The motor spins free right now (plugs removed)
2) Any thoughts on the cause of this (other than my not tightening the set screw correctly.
3) Any thoughts on the out of time/backfire symptoms?
Thanks a bunch ahead of time!
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