On this tutorial, we will cover how to make a complete rotor swap on your chipper shredder. The model utilized here is the chipper shredder 2090, but the concept is pretty much the same on all of our chipper shredders. This tutorial will serve you well if you need to remove the rotor to perform maintenance or a rotor swap.
For this tutorial, we will use:
1- Can of penetrating oil spray
1- Hex key 1/8" (Allen key)
2- Hex wrenches 9/16"
2- Flat screwdrivers (chisel optional)
1- Small hammer or mallet
1- Pulley extractor
1- Oil dispenser, grease
Strips of 280-grit sanding paper (or higher)
Before starting this tutorial, remove the belt guard and belts beforehand (Make sure the engine is OFF). On how to remove/reassemble the belts, please refer to the following tutorial here.
Spray the bearing unit with penetrating oil. Make sure to aim directly at the shaft and bearing housing contact (use the straw). Let it sit for approx 20 mins.
Loosen the 2-housing socket screws with a 1/8" hex key (Allen).
Remove L-shaped pins and safety hairpins.
Remove the screen from the chipper.
Insert a piece of wood or another suitable piece to block the rotor from rotating.
Remove the shaft center bolt with a 9/16" hex wrench or use a socket driver.
Remove the 1/4" hub bolts with a 7/16" socket and place them on the other holes, tighten them to push the pulley away towards the bearing, and free the hub. The pulley must be sitting completely away from the hub.
If the pulley is free but the hub is too tight to slide it out by hand, place a pulley extractor and bring the pulley out along with the hub as shown in the picture.
Once the pulley has been removed, loosen the bearing housing set screws. Apply penetrating oil to the shaft bearing contact area and let it sit for 20 mins.
Loosen the bearing housing bolts with 2- 9/16" hex wrenches. Make sure to utilize a wrench from the inside to stop the bolt's head from spinning.
Loosen bolts from the chute side with only one 9/16" hex wrench.
Gently tap on the bearing housing with a small hammer to shake off the contact area and improve the penetrating oil reach. This will help in removing the bearing.
Use a flat screwdriver to lift one end of the bearing housing. This will require adding significant stress to the tool. Apply a good amount of lever action towards the end of the shaft and see if the bearing is moving out.
If it's too stuck, utilize an additional tool such as a chisel to help extract the bearing housing as shown in the pic. We use some scrap plywood to protect the paint and keep some lever action on the housing.
Once there is sufficient room, utilize a pulley extractor to bring the bearing out.
Repeat the same steps 14-17 on the bearing from the transmission side. Before sliding it out make sure to sand the shaft to remove rust with a 280 grit sandpaper and after sanding, apply a thin film of grease.
Loosen shredder chute bolts, and flanges, and remove.
Remove the top.
Remove all bolts attaching to the side frame and remove them. Make sure that the rotor is supported underneath.
Remove the rotor. At this point, we are halfway through replacing the wood chipper rotor.
Clean the area and components before performing a reassembly.
Clean inside the machine and components. Sand with 280-grit paper inside the bearing to remove rust, debris, and any grease sludge. Then, apply a thin film of oil.
Apply a thin film of oil to both shafts on each side.
Insert the rotor, and make sure the non-wrapping disk (flat 1/2" steel donut) is already in place. Make sure to put a piece that supports the rotor underneath as described in step 21.
Insert back side frame. Please note you must insert bearing bolts BEFORE sliding the shaft.
Apply a dab of oil to the shaft and insert the bearing housing. Align holes with the non-wrapping disk and insert bolts. Please note you must make sure that the bearing grease nipple is pointing outwards of the frame, otherwise, you would not be able to utilize it for regreasing in the future.
Align holes with the help of a screwdriver or a round shaft and insert bolts. Repeat steps 27-28 on the other side.
Once bolts are assembled onto each bearing unit, put them back together with the frame (top cover, chute flange, etc) else BEFORE tightening bearing bolts. Bearing bolts shall be the last fasteners to be tightened.
Once the frame is assembled and the bolts are tightened. Proceed to tighten the bearing bolts. Preload each bearing bolt to make sure the rotor sits well and allow the bearing unit to self-align, before giving the final tightening.
After each bearing housing is tightened, spin the rotor and make sure is rotating freely. Proceed to tighten socket cup screws.