Flywheel removal

[urbainvh]

There were 2 bolts in the flywheel, those on the same line. In the 3th hole there was none. So i only screw a bolt in that hole, but I overtighten it and a little piece broke on the back. Does the bolt has to be screwed as far as possible? Does the bolt pull the flywheel from the shaft? Or can i use a puller in combination with that bolt that is screwed in?

Thank you!

 

[ThomasH]

I suspect that you need to talk to someone who works on that brand of chipper. I have heard of them being threaded, both right hand and left hand threads depending on the rotation direction. It will unscrew the opposite way that it is cutting if it is threaded. There are also split hubs as others have mentioned, that you screw bolts that are long enough in through the bolt holes to press against the inner hub and it pushes out the outer hub. There are some with screw on hubs, but I don't think yours is because I see nothing like spanner holes to remove a screw on outer hub. And of course it could press on, but I doubt it.

 

[pycoed]

Have a look for Keith Fenner's channel on Youtube. He is a machinist, & one of his excellent videos covers removing a flywheel (or maybe bearings) with a taper lock hub from a very large chipper (150hp plus!). He like you broke a piece off when trying to separate the hub pieces, but I can't remember how he got the parts apart in the end, but it was all on the video.

 

[SPIKER]

As been suggested it appears to be a two bolt taper lock bushing set. It is a 2 part device, they are pulled together and WEDGE onto the shaft. (The inside taper and inside cone pull together very tightly, they are slip fit & partly split so when tightening they wedge against the shaft and each other & the inside dia of the flywheel/pulley.)

You should have been able to remove the two bolts, take one of the bolts and screw it into the 3rd offset hole. it will bottom out onto the inside half of the taper lock and PUSH the two half apart. Sometimes these things are a pain, rust can seat/seal the two together as well.

The two bolts 180deg apart pull the two halves "together" and the Taper when pulled onto each other "LOCK" the pulley/flywheel in-place. When putting them together you have to account for belt alignments as the pulley & taper come together it moves them so be aware when re-assembling. Trial and error may be needed so once you do assembly one or two you will understand how good they are and how much a pain they can be


use some good penetrating oil sprayed into all 3 holes, you can use a punch to hammer backwards the inside piece on SOME of them but not all. The soft punch (Brass/bronze/cold rolled shaft) should be used while the bolt in the 3rd hole is tight against the bottom. tap on other side of the hard inner taper lock bushing, working around some. Do same with the 3rd bolt tighten it real good & leave it tight for a while and give a few wacks. Pull out bolt spray into it and the 2 tightening holes, re-tighten the 3rd bolt against the base. In a few cases you may have to drill additional holes like the 3rd hole, they can be taped into the outer half of the taper lock or you can use a punch thru them with just the 3rd bolt being tight.

Be aware when these things pop sometimes it is like a gunshot, including high velocity parts flying out.

The Taper Lock can be sacrificed as long as you dont damage the flywheel. In a case like this the outer part of the taper lock can break off leaving the tapered inner part against the shaft the outer cone shaped part that is between the flywheel and inner taper would need to be hammered in (the flywheel actually will go closer to the body of the chipper.) the inner taper on the shaft should stay put but not always... :

FYI New ones or lager ones will use 3 bolts to pull together and 2 to push them apart for above reasons.
Mark