I thought by now owners of the 5000 series would have replied - so I'll try based on how the 3000 and 4000 series PTO works.
The first thing to check is that the pto cable assembly is attached properly and/or is not rusted which might cause the pto from not completely disengaging the clutch disk in the assembly. The sparks and smoke suggest metal to metal which might suggest a radial bearing inside the clutch assembly finally met its maker and will need to be replaced. If so you will have to remove the pto clutch assembly.
It appears from the symptoms you describe that the assembly isn't releasing and is essentially dragging causing the engine to bog and/or die.
Inside the assembly there is a disk called a brake disk which should stop the assembly from rotating when you disengage the pto.
The clutch disk is keyed and rotates with the crankshaft and spins on and with crankshaft. When the pto is engaged the clutch disk is clamped against the pressure plate which is also attached to the pto pulley which drives the belt back to the mower deck and also the front PTO shaft.
When you release the pto the clamping force of the pressure plate should release itself from the clutch disk. The brake disk should take over and stop the pressure plate which is also attached to the pulley from spinning with the crankshaft. The pto pressure plate assembly freewheels on radial bearings on the crankshaft. See diagram below #26.
Search on pto assembly and/or dave4514 - who has an excellent post on the repair of the pto with pics. I wish this forum had stickies so this type of repair post like Dave's and Bob's and others would always be at the top of this forum.
I was told the clutch on the 5000 series is similar to that on motorcycles - immersed in oil - so doubt it has anything to do with the drive clutch.
Schematic of pto assembly
http://www.boats.net/parts/search/H...# FAHA-4300001/FRONT P.T.O. CLUTCH/parts.html
Schematic of drive clutch assembly
http://www.boats.net/parts/search/H...TOR, JPN, VIN# FAHA-4300001/CLUTCH/parts.html
It's also probable the radial bearing in the pto front drive shaft assembly below might have failed instead of the pto clutch assembly.
Schematic pto front shaft
http://www.boats.net/parts/search/H...N# FAHA-4300001/FRONT P.T.O. SHAFT/parts.html
Note: I don't own a 5000 series. I do own 2 3813's, one 4213, and one 4514. From the parts schematics it appears the pto on the 5000 series is similar to the 3000 and 4000 series and works essentially the same way.
HTH - repair yourself and you will save a ton of money
The first thing to check is that the pto cable assembly is attached properly and/or is not rusted which might cause the pto from not completely disengaging the clutch disk in the assembly. The sparks and smoke suggest metal to metal which might suggest a radial bearing inside the clutch assembly finally met its maker and will need to be replaced. If so you will have to remove the pto clutch assembly.
It appears from the symptoms you describe that the assembly isn't releasing and is essentially dragging causing the engine to bog and/or die.
Inside the assembly there is a disk called a brake disk which should stop the assembly from rotating when you disengage the pto.
The clutch disk is keyed and rotates with the crankshaft and spins on and with crankshaft. When the pto is engaged the clutch disk is clamped against the pressure plate which is also attached to the pto pulley which drives the belt back to the mower deck and also the front PTO shaft.
When you release the pto the clamping force of the pressure plate should release itself from the clutch disk. The brake disk should take over and stop the pressure plate which is also attached to the pulley from spinning with the crankshaft. The pto pressure plate assembly freewheels on radial bearings on the crankshaft. See diagram below #26.
Search on pto assembly and/or dave4514 - who has an excellent post on the repair of the pto with pics. I wish this forum had stickies so this type of repair post like Dave's and Bob's and others would always be at the top of this forum.
I was told the clutch on the 5000 series is similar to that on motorcycles - immersed in oil - so doubt it has anything to do with the drive clutch.
Schematic of pto assembly
http://www.boats.net/parts/search/H...# FAHA-4300001/FRONT P.T.O. CLUTCH/parts.html
Schematic of drive clutch assembly
http://www.boats.net/parts/search/H...TOR, JPN, VIN# FAHA-4300001/CLUTCH/parts.html
It's also probable the radial bearing in the pto front drive shaft assembly below might have failed instead of the pto clutch assembly.
Schematic pto front shaft
http://www.boats.net/parts/search/H...N# FAHA-4300001/FRONT P.T.O. SHAFT/parts.html
Note: I don't own a 5000 series. I do own 2 3813's, one 4213, and one 4514. From the parts schematics it appears the pto on the 5000 series is similar to the 3000 and 4000 series and works essentially the same way.
HTH - repair yourself and you will save a ton of money