I have a Scag tiger cub STC52A with the honda24 hp engine. The engine will bog when the PTO is engaged. Deck spindles spins freely and belt replaced. There is spark from both cylinder plugs and carb has been replaced as well. The engine seem to run normal without PTO engaged. Sometimes it will stall and at other times it slows way down and takes about a minute to get back up to speed but will still bog at the slightest hint of a blade of grass. Any suggestions?
Power loss when PTO engaged
DOUGE2
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I have a Scag tiger cub STC52A with the honda24 hp engine. The engine will bog when the PTO is engaged. Deck spindles spins freely and belt replaced. There is spark from both cylinder plugs and carb has been replaced as well. The engine seem to run normal without PTO engaged. Sometimes it will stall and at other times it slows way down and takes about a minute to get back up to speed but will still bog at the slightest hint of a blade of grass. Any suggestions?
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Sounds like it's only running on one cylinder.....
Start the engine and set throttle just above idle, Remove one plug wire at a time (with rubber handled pliers) and see if it shuts down. If it does check the valves/rockers and push-rods on the other side.
Start the engine and set throttle just above idle, Remove one plug wire at a time (with rubber handled pliers) and see if it shuts down. If it does check the valves/rockers and push-rods on the other side.
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Is the governor working?
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It's hard to tell with the bogging being so bad.
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Can you safely move the governor arm while Pto is engaged? It will take a second person or something on the OPC.
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cgaengineer, There's no need to go there with the below info, It's only running on one cylinder, apparently a faulty coil but I'd replace the plugs first....
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Oh I see that now...missed that part, was going off first post.
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Just swap the plugs just to make sure that isn't the issue, If not then swap the coils from one side to the other and see if the loss spark follows to the other side. If so replace the coil, Set the coil to flywheel air gap at 0.10" to 0.12"....
If you have no spark there's no need in checking valves etc, I only mentioned that because you said you had spark in your first post.
If you have no spark there's no need in checking valves etc, I only mentioned that because you said you had spark in your first post.
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I swapped plugs from one side to the next with the same results as before; however I am getting spark from both sides. I hooked a spark checker to the side where; when I pulled the plug there was no change, there is a continuous spark.
If I plug it back in and pull the opposite side it immediately shuts down. So I guess I'm back to the previous advice given earlier about the valves
rocker arms ect. which is probably beyond my expertise.
If I plug it back in and pull the opposite side it immediately shuts down. So I guess I'm back to the previous advice given earlier about the valves
rocker arms ect. which is probably beyond my expertise.
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That's what it appears, you can pop the valve cover off and look for a rocker off the valve or loose, or bent push-rod. If you find nothing obvious rotate the engine by hand and make sure both valves open and close, Then check the adjustment as below;
Ok. I finally got around to pulling of rocker cover and both valves seem to be in tact.
I'm not real familiar with small engines but both valves move when engine is turned so I dont think anything is bent or broken. Does ones side supposed to be really loose when the other is in the exhaust or compression stroke? I will attempt the adjustment procedure next.
I'm not real familiar with small engines but both valves move when engine is turned so I dont think anything is bent or broken. Does ones side supposed to be really loose when the other is in the exhaust or compression stroke? I will attempt the adjustment procedure next.
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Yes one side will be loose compared to the other. As far as adjustment procedure you need to first look up specs and than adjust at TDC with engine warm/cold depending on what's specs say.
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I intend to use these.That's what it appears, you can pop the valve cover off and look for a rocker off the valve or loose, or bent push-rod. If you find nothing obvious rotate the engine by hand and make sure both valves open and close, Then check the adjustment as below;
![Image]()
![Image]()
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