Clutch Install Questions

[Baketown Scotty]

Hello All,

Finally got a 3HP Predator motor for our first go kart build. The keyway in my clutch is only about 1'' long and does not allow the clutch to go very far on the crankshaft. I thought this clutch (Max Torque #35) would mount inboard or outboard but the keyway does not go all the way through so it can only be mounted as shown. Is this OK so far out on the shaft?
The paperwork that came with the clutch says the keyway should be 1/2'' long max. It is about an inch. Should I cut the keyway so it will slide farther on?
Thanks

Scot

 

[mckutzy]

The clutch needs to sit all the way back against the shaft shoulder as far as it can...
Cut the key for a little as it needs to be... but the clutch needs to be fully seated on the shaft with a bolt for securement...Inboard or outboard...
Move the motor to keep alignment... or the shaft will be torqued and cause premature wear and other problems...

 

[Mac]

Looks like the key stock has been located at the end of the crankshaft, it should be possible to slide the key stock toward the block, so the clutch will slide onto the shaft further.

 

[mckutzy]

No, the milled cut is swept up as they use a woodruff key cutter to mill the shaft.
The clutch has a short section of keyway in the bore of the driver, so the key is only about 1/2"-3/4" long..

 

[Baketown Scotty]

OK, so the keyway slot goes almost the length of the crankshaft. I can cut the key shorter to allow the clutch to slide on further. How do I stop the clutch from going all the way against the block? Do I install some type of washer that sets against the ridge on the crankshaft or will the key stop it from moving at the point the keyway starts to sweep up?
If the clutch gets installed as far as it can and I install a bolt and washer on the end of the crankshaft, there will be a space between the washer and the clutch. Is it OK for the clutch to slide along the shaft some or do I need to lock it down with set screws?
Sorry for the questions that may seem silly to most but I just don't know any better. Thanks for the help.

Scot

 

[mckutzy]

It should all the way against the shoulder of the shaft.... If the clutch hub or sprocket binds with the side plate, space it off till it clears from the obstruction.
If there is space in front aswell, to the end of the shaft, put a few washers till it almost covers the length of the shaft, then secure with a bolt/washer on the end of the shaft.....

Make sure the bolt/washer isnt tightening against the clutch itself, should be a little play and be free.

Some say use the setscrew or shaft bolt, I use both just to make sure. In this exact type of clutch, the setscrew helps to keep the key in the hub and the other keeps it on the shaft.
I would just use the keyway setscrew and use a shaft bolt on the end. Use Blue loctite(NOT RED) to secure both screw/bolt.

 

[BigWes]

It should all the way against the shoulder of the shaft.... If the clutch hub or sprocket binds with the side plate, space it off till it clears from the obstruction.
If there is space in front aswell, to the end of the shaft, put a few washers till it almost covers the length of the shaft, then secure with a bolt/washer on the end of the shaft.....

Make sure the bolt/washer isnt tightening against the clutch itself, should be a little play and be free.

Some say use the setscrew or shaft bolt, I use both just to make sure. In this exact type of clutch, the setscrew helps to keep the key in the hub and the other keeps it on the shaft.
I would just use the keyway setscrew and use a shaft bolt on the end. Use Blue loctite(NOT RED) to secure both screw/bolt.

When given the option I use both methods as well, just as mckutzy does...if I am forced to use a centrifugal clutch. Bellville washer backed up with machine shims to prevent the clutch from walking in and an index washer on the shaft bolt to prevent it from walking out. I also allow several thousandths gap so the clutch will have wiggle room. It needs to be able to float a bit without binding especially as it heats up. The outer clutch bell does. Dirt and other crap will tend to migrate in there over time anyway. Leave room for that. You will need to clean it periodically and service it as well.

Good luck.

 

[Baketown Scotty]

Really appreciate the help Thank you.

 

[Baketown Scotty]

Finally got it complete. Moving in to try a Tarantula now.

 

[Kent]

It's a cute little bugga !!