6000 ZT Bogging down when PTO engaged.

PTmowerMech

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6000 ZT
S# BBZ6027K002102249
Kohler
M# SV840-3012
S# 4003614973

Major bogging when I engage the PTO. Cleaned out the fuel lines, drained some water from the tank and the carburetor bowl. Replace the fuel pump & filter. Got it starting and running way better.
When I engaged the blades, 80's of the time, it bogs way down. 20% of the time, it's normal.
All the idlers are fine. The spindle bearings sound dry. But there's no grease fittings. So they'll have to be replaced. But I don't think that has anything to do with the engine bogging, since the spindle bearings are still loose and turn freely. They're just noisy.

Top idle RPMs is reading 3000rpm. After the engine bogs then get's back up to speed, it does fine.
 

PTmowerMech

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Thinking deeper into this. could the carb still be needing a good cleaning? I noticed ever so often it wants to cough.
 

bertsmobile1

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prime suspect is one dead cylinder
I had 2 customers with mowers that had a dud cylinder from new and they never realised this till after I did a service and fixed the faults
They thought the engine bogging down when the PTO was engaged was normal .
 

StarTech

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Yes it can be the carburetor as I had a CV680-3016 doing the very problem with a single barrel Keikin carburetor on an Exmark back in August this year..
 
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PTmowerMech

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prime suspect is one dead cylinder
I had 2 customers with mowers that had a dud cylinder from new and they never realised this till after I did a service and fixed the faults
They thought the engine bogging down when the PTO was engaged was normal .

I took the RPM reading on both cylinders. Both read 3000.

When you say "dud," I'm guessing you mean it ain't getting any fire from the coil. Or are you talking about a valve issue?
 

PTmowerMech

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Yes it can be the carburetor as I had a CV680-3016 doing the very problem with a single barrel Keikin carburetor on an Exmark back in August this year..

I drove it around the garage to the back shop, where the lift is, and just for funzies, I engaged the PTO, and it didn't bog a bit. Tried it a couple more times, and was working fine. Then right before I pulled it into the bay, I pulled the button and it bogged so bad it almost died.
 

PTmowerMech

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Ok, so I've replaced all the contaminated fuel, rinsed out the carb and it's running better. It's not coughing anymore. Cranks easier. Changed the spindle bearings, rechecked all the idlers. And changed the plugs.
But still on first pull of the PTO button it still bogs down and dies.
Now, I can pull and push the PTO button quickly, let it get back up to speed (like 2 seconds) then repeat that a couple of times and all is well. But first couple of pulls on the PTO button, it's a no go.
 

StarTech

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I took the RPM reading on both cylinders. Both read 3000.

When you say "dud," I'm guessing you mean it ain't getting any fire from the coil. Or are you talking about a valve issue?
Question are you doing this with the opposite cylinder plug wire disconnected at the time or with both plugs wires connected? If both connected then that just indicated that ignition is working but could still valve problem.
 
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