Electronic Clutch Dis-Engages-- Need Help

[vern66]

Lawn Mower type and Description:

Cub Cadet LT1045 46 inch Mower Deck
Model: 13RX11CH756 621-879
Serial Number: 1F137H10222
Date of Mfgr: 6-2007

Battery is new and fully charged -- and 360 amp which is somewhat more amps than normal Minimum for this category of Lawn Mowers. Manual shows as using a 235 amp battery.

This Lawn Mower has an Electric Clutch for supplying power for turning the Mower Blades.
All Engine and Mower functions perform normal and without any type of problem -- with the exception that the Electronic Clutch stops as if Battery Power through the Clutch Switch is disconnected (turned off) during actual mowing. Of course, when this happens; the Mower Blades stop turning. I can push in (turn off) the switch then turn back on and it then functions normal for a period of time. This happens at varying frequencies with length of time being variable.

This issue occurs even when running Engine speed at full throttle but seems to be more frequent when using less than full throttle (less than full engine RPM). When the lawn grass is not dense, I prefer to not use full engine RPM.

Any suggestions to resolve this would be appreciated.

 

[Gearjammer]

I'd check to see that the reverse/back-up switch is working properly including the over ride switch which lets you back up and keep the mower engaged. Any of those safety switches could be kicking the electric clutch out of gear, so pay close attention to what was happening when it stopped. (Were you shifting around in the seat? etc...) Good luck. Gearjammer

 

[vern66]

I'd check to see that the reverse/back-up switch is working properly including the over ride switch which lets you back up and keep the mower engaged. Any of those safety switches could be kicking the electric clutch out of gear, so pay close attention to what was happening when it stopped. (Were you shifting around in the seat? etc...) Good luck. Gearjammer

Thanks for the reply. I have the seat safety switch (temporarily) disconnected -- so this one is out of the equation.
I will have to do some research (location, etc) regarding the others so I can check them. This Lawn Mower has been doing this for quite a long time but reason I am now trying to resolve this is because the usage has become the primary mower and before it was used primarily in late fall for leaf mulching

 

[Darryl G]

I suspect the air gap is too large for the magnet to hold the 2 contact plates together. If you have an adjustable clutch try adjusting it. You should be running at full rpms whenever you are mowing unless you need to temporarily throttle down for a bare dusty section or something.

 

[MowLife]

I worked on a government contract where we used hustler zero turns and this was a common problem. Most of the time it was a bad pto switch. If you can get down there with a volt meter when it cuts off to see if your getting proper voltage will narrow it down. If your getting voltage from the wires at the cluch at the time it cuts off you have a clutch problem. If not then probably a bad pto switch. Other safety switches may tie into pto switch that you can easily test by ohm testing the switches.

 

[vern66]

I suspect the air gap is too large for the magnet to hold the 2 contact plates together. If you have an adjustable clutch try adjusting it. You should be running at full rpms whenever you are mowing unless you need to temporarily throttle down for a bare dusty section or something.

Thanks for your reply: How is the best way to determine if the clutch is adjustable -- preferably while it is in the present installed status. I have not checked to see if this information is included in the parts list for the clutch.
I don't recall seeing tyhis but I will (of course) check for this again.

 

[vern66]

I worked on a government contract where we used hustler zero turns and this was a common problem. Most of the time it was a bad pto switch. If you can get down there with a volt meter when it cuts off to see if your getting proper voltage will narrow it down. If your getting voltage from the wires at the cluch at the time it cuts off you have a clutch problem. If not then probably a bad pto switch. Other safety switches may tie into pto switch that you can easily test by ohm testing the switches.

That could be slightly difficult and I believe the engine may have to be turned off in order to check this otherwise it could be slightly dangerous especially should the clutch make contact and start running again. Also, turning off the switch would lose all DC voltage from the battery. However, I first will check all contacts on the Clutch switch to be sure there is good contact with the switch connections which (without looking yet) I expect the connections are "slip on" types.

I also will apply Caig contact Cleaner & Enhancer on the connectors.

 

[Darryl G]

Adjustable clutches usually have 3 nuts on the face arranged in a triangle that are used for adjusting it.

 

[vern66]

Adjustable clutches usually have 3 nuts on the face arranged in a triangle that are used for adjusting it.

I did a quick check by hoisting the front part of the mower up so to see the Clutch assembly. However, honestly it is so dirty (also didn't have adequate lighting) that with my quick review I did not see what you have described. I plan to call Cub Cadet in the morning and find out if the original Lawn Mower assembly used the adjustable type of clutch. The Manual only supplies the name and part number (717-04174A) but does not indicate if it is the adjustable type.

I believe it is probably the non adjustable type. If it is not adjustable, I prefer to not remove it without trying to find the issue as described for it to occasionally stop working properly -- due possibly by some mal-functioning of any of the items discussed by various posts.

 

[bertsmobile1]

You can download the repair manual for you mower from Cub, it is a free download but you will need all of the numbers off the ID tag either under the seat or behind the front left wheel on the frame rail
There are a few reasons that clutch fail
Incorrect air gap ( already mentioned ) put a charger on the battery & engage the clutch, it should stay engaged till the battery goes flat ( hence the charger )
faulty switch ( also already mentioned )
Broken wires , usually at or just inside the clutch, turn the clutch on then wiggle & pull the wires.
Bad ground contact ( voltage will be less than 12 V at the clutch plug )