Greenmech 19-28 arborist 2013

[Terjef]

Hi,

 

I just purchased a Greenmech 19-28. It's from 2013 with 440 hours on it. It's working fine, but the shear bars are a little rounded so I wanted to flip them round. 

Does anyone have any pointers and important-to-knows? 

Seems like the hex bolts are very very hard to loosen on the top shear bar. And it's close to impossible to get a decent grip because of hydraulics and so on. Not enough room. 

So just any pointers would be great, if you've wrestled with it?

 

Thanks in advance!

[PeteB]

The GreenMech Service department is still open. Call 01789 400044 and press 2 at the prompt. Jase Hutchinson,  the Manager is available on here too. He will no doubt respond later.

[Jase hutch]

Hi Terjef,

The top shearbar is held on with two 12 mm fine threaded bolts so you’ll need a 19mm socket .

These bolts pass through the back bearing housing and have spring washers and ‘Loctite’ and are torqued up to 100Nm.

It’s normal for these to feel tight coming out due to the ‘Locktite’ 

The shearbars are always far easier to replace/turn with the flywheel removed !

Also , when turning or replacing shearbars , before clamping/bolting in place , convince yourself first that you don’t need to chamfer an edge off that could cause a problem with introducing a step and thus a restriction for material being fed in.

This can happen over time due to the actual steel fabrication becoming worn.

 

 

The vertical shearbar has a single 12mm ‘pusher’ bolt passing through a tapped steel block welded to the flywheel housing wrap , slacken off the plain locking nut and back off the bolt several turns.

If the bolt is reluctant to move I would give it a soaking in penetrating oil or get some heat on the block , ‘don’t shear it off as it’s difficult to replace’ !

Now look at the bottom of the vertical shearbar and you’ll see a clamping arrangement.

Slacken off the locking nut on the vertical 10mm bolt and release the bolt a few turns.

Now , using a 13mm spanner , remove the threaded block that this 10mm bolt passes through.

Next you need to remove the chamfered clamping plate that pushes on the base of the shearbar , it’s held on with two 12mm bolts and these can be other hex head or cap head.

That’s  it , the vertical shearbar is now ready to come out but it will likely be tight .

If you look at the top end of the shearbar you will see a hole , about 11mm in diameter, if you weld a stud at ninety degrees to a piece of steel bar and locate the stud in the hole (you’ll need to clean the hole out) and give it a good smack with a sizeable hammer you’ll be able to knock the shearbar down and out.

The bottom shearbar is held in with two 12mm bolts , once they are removed this can be knocked up and out of the machine , you can just get a long punch on either end to knock it upwards. This again can be tight and a little awkward.

 

With all the shearbars out , it’s imperative to clean all the mounting faces.

Clean the  shearbars , we do this using a scraper first and then a soft pad on an angle grinder.

With the bottom shearbar , torque the 12mm bolts to 100 Nm. Make sure the shearbar is pushed up tight to the vertical shearbar before doing so , I leave this one loose until the vertical shearbar is tight !

With the top shearbar , Loctite the threads and torque to 100 Nm.

With the vertical shearbar , bolt up all the clamping parts at the bottom of the shearbar , tighten the two 12mm clamping bolts to 100 Nm and then tighten the 10mm pusher bolt and then using a hammer and punch , tap the part that you’re pushing with the 10mm bolt , tighten the bolt again and then tap again. Keep doing this until you’re confident the shearbar chamfered clamping plate is as tight up against the shearbar as possible.

Now tighten the 12mm pusher bolt in the threaded block on the wrap so it pushes firmly against the shearbar and then tighten its locking nut.

 

Thats it , job done..

[dig-dug-dan]

Nice to see a company answering the question for all to see, not just refusing and telling you to ring a number!

[Terjef]

Hi Jase,

 

Thank you very much! I'll try and get it out this evening. Will reply with either success or failure.

[monkeybusiness]

They are a bit of a bitch to do in honesty, and I wouldn’t even attempt the job without removing the flywheel first... However, if you are that far into the machine it is well worth the effort as these chippers are phenomenal when set up right! 

[Terjef]

Is there a trick to getting the two allen m12's out? The ones holding the chamfered bar? There is absolutely no room.

[Jase hutch]

Oh yeah , we use a home made Allen key .

If you have a standard 10mm allen key , cut the long leg off with a grinder keeping it as long as possible  then cut this in half and lay one piece on top of the other and overlap it by 15-10mm then weld the two pieces together , this will give you a 'stepped ' Allen key. Then fit it into a 10mm socket,  you can then use a power bar and several long extensions and undo the bolts from behind the fuel tank..

I hope this makes sense ?

Jase.

[Terjef]

Thanks! I actually pushed the fuel tank a bit forward. That way I could get in behind and undo them. now I just need the "pusher" bolt... This really is a bitch of a job! 

[Terjef]

By the way, why would it help with the flywheel out? Seems like everything is done underneath.