Blades too Tight

bigge31566

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I have a 72" Bunton and every time I change the blades the impact will not remove the bolts, I have to get a pull bar and cheater even after using anti seize, and trying to hold blades way too much, I put them on with impact, is there any different washer or something I can do to prevent this
 

MBDiagMan

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What kind of impact are you using? I've used an ingersoll 1/2" impact with 10si shop air for many years with no issues. It sounds like you need some more oomph on your impact when taking them off.

Larry
 

motoman

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There have been previous threads on blade bolt grading, lubing , torque , torque reduction after lube, and impact wrenches. Try searching keywords in this forum.
 

djdicetn

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I'm using a 1/2" IR with 90 psi

I just installed a mulch kit on my Gravely and the instructions stated to torque the bolts to 115-120ft/lbs when installing the mulch blades. I had to "wedge the OEM blades with channel-locks and a piece of plywood" underneath the deck to break the bolts loose and remove them. Seems to me that that torque setting is abit excessive if my automobiles recommend 100-110ft/lbs. Why would blades need to be torqued higher that wheels on a car?????
 

MBDiagMan

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Your car has multiple lug bolts/nuts that are not subject to rotation that requires a friction fit. A 1/2" break over bar and the correct size socket will apply that much torque without too much trouble.

Larry
 

motoman

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This forum has provided a "from scratch" or backup reference for bolt , torque, thread lube considerations. Suggest it be used after trying to get the manufacturer's values. Air wrenches can help, but are destructive if misused. Use the search function.
 

bigge31566

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Thanks for all the info, I think I will start to tighten with ratchet and loosen with impact to see if it makes a difference
 

andy135

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On most impact guns the loosen torque is always bigger than the highest setting tighten torque. I started from lightest setting then check with torque wrench. Now I know the second highest setting is good enough.
 

Lawnboy18

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I just installed a mulch kit on my Gravely and the instructions stated to torque the bolts to 115-120ft/lbs when installing the mulch blades. I had to "wedge the OEM blades with channel-locks and a piece of plywood" underneath the deck to break the bolts loose and remove them. Seems to me that that torque setting is abit excessive if my automobiles recommend 100-110ft/lbs. Why would blades need to be torqued higher that wheels on a car?????

That is a lot! I just tighten mine until they are more than snug kinda. Well, until I cannot turn them anymore. Works for me! 120 is almost as much as bolting a car head!!!:confused2:
 
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