Chipper Runout on chipper shredder sheave

[JackyJ]

I've just acquired a new MacKissic PTO chipper shredder and I'm addressing several concerns with the manufacturer. One is a distinct wobble in the sheave attached to the pto shaft. The sheave is 14" in diameter and I measure the runout at about 0.1" You can see it in the video below where the tractor is idling.

What is a typical runout tolerance for something like this?

Jack

 

[Shaneard]

Take a rubber hammer and smack it on the high spot, rinse, lather & repeat. It is a lot of run out on something new but nothing to lose sleep over.

 

[sweettractors]

I've just acquired a new MacKissic PTO chipper shredder and I'm addressing several concerns with the manufacturer. One is a distinct wobble in the sheave attached to the pto shaft. The sheave is 14" in diameter and I measure the runout at about 0.1" You can see it in the video below where the tractor is idling.

What is a typical runout tolerance for something like this?

Jack

It looks like the pulley is not seated aganist the shaft collar that I see on the right side? Do those bolts need to be tightened? Ken Sweet

 

[JackyJ]

It looks like the pulley is not seated aganist the shaft collar that I see on the right side? Do those bolts need to be tightened? Ken Sweet

I did check those and everything is snug/tight. Seems to me that either the drive shaft itself has some runout, or the sheave is slightly warped. Maybe a bit of both, but since the two are keyed together I can't change their relative orientations to see if that would help.

 

[sweettractors]

I did check those and everything is snug/tight. Seems to me that either the drive shaft itself has some runout, or the sheave is slightly warped. Maybe a bit of both, but since the two are keyed together I can't change their relative orientations to see if that would help.

if the hub bolts go thru the pulley, can you tighten/loosen to affect the runout? Ken Sweet

 

[JackyJ]

if the hub bolts go thru the pulley, can you tighten/loosen to affect the runout? Ken Sweet

That's a good idea--I checked to make sure everything was snug, but maybe I can make some adjustment there. Thanks for the suggestions--I will give it a try!

 

[Tractor Seabee]

Two piece sheaves with a tapered center hub are vulnerable to un-equal tightening of the bolts. You need to use a torque wrench to assure even tightening. I am surprised to see only one belt. My 6" chipper had 4 belt sheaves. The length of the wider hub helps prevent the distortion you can get with single belt arrays. Unless you hipper is in the 2" range you will replace a lot of belts and be adjusting them a lot if used much. Belts too tight can also distort those single belt assemblies. Do you have any specs on the chipper like US made stuff comes with? A belt asnd sheave supplier can provide you with torque ratings, new ones come with that info. A dial indicator can be a good diagnostic tool for this also. Shaft end play came come into the equation also as well as worn/imperfect bearings. A bearing pillow block not bolted down tight also comes into mind. Never know what gets past factory QA.

Ron

 

[JackyJ]

Two piece sheaves with a tapered center hub are vulnerable to un-equal tightening of the bolts.

Thanks Ron--this sort of hub/bushing is new to me, and it looks like I need to get some details on it. I found some installation info on Browning hubs with torque specs, but the parts list on my chipper doesn't tell me any details on which hub I have. Hopefully the chipper manufacturer can help me out with this and it is just an adjustment issue--I'm waiting to hear back from their service manager who is out of town this week.