Cub Cadet 1515 Low Power when PTO Engaged

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I set everything up per the manual. And I didn't notice any improvement. Im starting to think this is a lost cause. I have a tach that counts spark plug pulse.

At full throttle no load its running around 4000-4100RPM.
At full throttle driving no PTO its running around 3700RPM
At full throttle driving with PTO its running about 2400RPM

So the governor isn't keeping the speed up. Its got plenty of power until the PTO is engaged. Here are some pics the the current setup.

Capture1.JPG
Capture2.JPG
Capture3.JPG

The engine manual shows the following. Whats interesting is that it shows the throttle cable in all the positions connected to inner (smaller) lever and shows the choke cable in all the positions connected to the half moon lever. This is wrong according to my lawnmower.
Capture4.JPG

Any other ideas what I can try next? Thank you for the help!
 

bertsmobile1

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I seriously doubt that the diagram is wrong
What does happen is people hook the control rods to the wrong butterflys
This is very common .
Remove your control cables then move the high idle screw and see which arm moves
That arm is the one which should be connected to the governor arm via a spring
The other one should go directly to the choke butterfly which is the one closest to the air filter.
 
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When I was looking at the diagram, I had the same thought that maybe I too swapped the cables by accident.

I checked this and the throttle cable moves the arm that controls the butterfly valve that is connected to the governor. The choke moves the butterfly valve closest to the air filter.

I even tested this. Running at full throttle and engine warmed up if I move the choke ever so slightly it cuts air supply off and almost kills the engine.

Im pretty confident I have these connected to the right butterfly valves.

My pics attached in the post above are my current setup as described here in this post so I really do think they flipped flopped their labeling.
 

bertsmobile1

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To work, the throttle has to pull on the governor spring and nothing else.
It is the balance between the tension in the governor spring and the pressure from the governor that works against that spring that actually controls the engine speed.
The throttle cable simply controls the tension in the spring not the butterfly directly .
 
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Thanks! The throttle cable does move the governor lever which tensions up the governor spring. But there is definitely no governor movement under load or really any condition. Ill see if I can post a video later.
 

bertsmobile1

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Thanks! The throttle cable does move the governor lever which tensions up the governor spring. But there is definitely no governor movement under load or really any condition. Ill see if I can post a video later.
You have it connected wrong
The throttle cabe can not be connected directly to the throttle butterfly because that prevents the governor moving the butterfly without moving the throttle cable which it is not strong enough to do .
 

slomo

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I set everything up per the manual. And I didn't notice any improvement. Im starting to think this is a lost cause. I have a tach that counts spark plug pulse.

At full throttle no load its running around 4000-4100RPM.
At full throttle driving no PTO its running around 3700RPM
At full throttle driving with PTO its running about 2400RPM

So the governor isn't keeping the speed up. Its got plenty of power until the PTO is engaged. Here are some pics the the current setup.

View attachment 57124
View attachment 57125
View attachment 57126

The engine manual shows the following. Whats interesting is that it shows the throttle cable in all the positions connected to inner (smaller) lever and shows the choke cable in all the positions connected to the half moon lever. This is wrong according to my lawnmower.
View attachment 57127

Any other ideas what I can try next? Thank you for the help!
Is this an LS-1 Chevy engine?

4100 revs is getting up there. Might want to keep her under 3600rpm.

Page 5.14 to 5.20 in your pdf talks about the governor settings.

slomo
 
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You have it connected wrong
The throttle cabe can not be connected directly to the throttle butterfly because that prevents the governor moving the butterfly without moving the throttle cable which it is not strong enough to do .
From the pics I have attached to this thread, would you be able to mark up or point to where I need to move the throttle cable too? Thank you
 
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Is this an LS-1 Chevy engine?

4100 revs is getting up there. Might want to keep her under 3600rpm.

Page 5.14 to 5.20 in your pdf talks about the governor settings.

slomo
I went thru that. Im confused by the diagram on page 5.18 because it doesnt match my control plate.

Yeah I know its over speeding a bit, but with a load its way under rpms so Im not really letting it overspeed too much. Ill turn it down once I can figure out this governor issue.
 
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