Removing brush hog blades

[ericm979]

The used brush hog I acquired last year has badly worn blades. I was able to remove the 600 ft-lb blade nuts but I could not get the bolts out of the carrier.

Bolt #33 is stuck in part #30. It's a shouldered bolt with a 1 1/8 threaded portion and about 1 3/8 shoulder that fits in the carrier and holds the blade. I doused it in penetrating fluid and beat on it with a pipe and an engineers hammer and an air hammer but it did not budge. Any ideas how to get it loose? If I do hit it with something heavier I will support part #30 from below so the bearings are not taking the force. I can get at it from below, or from above through about a 3"hole in the deck.

 

[scootr]

You could try heating it with a torch to break the rust bond... beyond that daily application of a rust buster solvent for a week or so may do the trick.
A second thought is a airchisle driven in between the blade and the center piece to add separation pressure then try the hammer once it is preloaded.
It may take a combination of all of the above. GL

 

[mrmikey]

Any way you can get a ball joint press in there, if not as scootr said, heat is gonna be your best bet.

 

[ericm979]

I was thinking heat. Would a decent hand held propane torch do or do I need Oxy-Acetylene? I've used propane torches on stuck fasteners with success before but the fasteners were a lot smaller.

There's no room for a normal gear puller unless I remove the blade carrier entirely. Then I could get at it from above without going through the 3" hole in the deck.

 

[scootr]

I've use handheld MAP gas for all sorts of heating projects, big pieces just take longer.
A bearing puller may help. I 've been know to get these as tight as I dare and whack em with a hammer.

 

[CalG]

Use two Burnze-o-matic hand torches.

 

[Hay Dude]

That’s weird cause mine usually just fall out.

 

[D&D]

I was thinking heat. Would a decent hand held propane torch do or do I need Oxy-Acetylene? I've used propane torches on stuck fasteners with success before but the fasteners were a lot smaller.

There's no room for a normal gear puller unless I remove the blade carrier entirely. Then I could get at it from above without going through the 3" hole in the deck.

If you have removed item 34 and 35, I would drive a wedge/chisel/air hammer in between the blade and carrier.

 

[Hay Dude]

Worst is being 20M from shop and bending a blade.
My bolts usually just fall out though.
My DeWalt impact has just enough azz to get them out of my CX-15

 

[skipmarcy]

On my very old Howse 6', the bolts also have a "pinched-up" key made into the tapered shoulder of the bolt to keep the bolt from turning which could be adding difficulty removing them. It's possible the bolt was/has spun and that key is wedging the bolt in even tighter. My personal opinion is a propane torch will be useless, need something much hotter to heat that much metal and a BIG hammer. You should always replace the bolts when replacing blades - they are a wear item too.

 

[EddieWalker]

Put a few blocks under the stump jumper and beat the bolt with a large hammer and punch. I think I used a length of rebar on the bolt and hit it with a 4 pound sledge hammer.

 

[Xfaxman]

Try an impact wrench on bolt #33.

 

[Chewwy]

If heating and/or rust solvent fails, cut the bolt flush with the blade; then drill out the center of the bolt.

 

[ericm979]

That’s weird cause mine usually just fall out.

I'm guessing that you replace yours more than once every 20 years. The unit looked in decent shape from above but I was in a hurry and didn't check the blades. They're worn to the point that they're just rounded off steel bars with no hint there was ever an edge. I doubt they have ever been replaced.

 

[ericm979]

Try an impact wrench on bolt #33.

It doesn't show on the diagram but bolt #33 doesn't have any flats. It's a thin round head. Also it's got a key that keeps it from turning.

 

[Xfaxman]

It doesn't show on the diagram but bolt #33 doesn't have any flats. It's a thin round head. Also it's got a key that keeps it from turning.

Thanks, that eliminates my suggestion.

 

[scootr]

Are they out yet?

 

[Hughman]

Ball joint press

 

[mjonesnh]

I'm guessing that you replace yours more than once every 20 years. The unit looked in decent shape from above but I was in a hurry and didn't check the blades. They're worn to the point that they're just rounded off steel bars with no hint there was ever an edge. I doubt they have ever been replaced.

Suspect the " key" on the bolt shank has spun in the stump jumper hole and locked up. If you support the stump jumper underneath so it cannot flex you may be able to drive bolts out with a piece of 1" steel rod. Had 1 on my Bushhog Squealer once do that and finally was able to drive the bolt out. Key had rotated a bit and wedged in bolt hole. 3 pound hand sledge and hardened steel rod finally beat it out.

 

[Mike1955]

It doesn't show on the diagram but bolt #33 doesn't have any flats. It's a thin round head. Also it's got a key that keeps it from turning.

So the big shoulder is in the blade. The spline part of the bolt looks like it presses in the stump jumper. Now how do you get a pressed in bolt out after years of rusting and all kinds of Temputure changes. I think it needs burning out with a cutting torch. If it’s possible to get to it. Only an opinion guys. Good luck