# 30" Rotary - Getting the blade off?



## Error401 (Jun 16, 2009)

Does anyone have any tips on removing the blade from the 30" rotary mower? I don't know when the last time mine was taken off for sharpening (has to be at least 10 years ago, and I didn't do it).

I found the wrench and it's the 106 head, but putting all my weight on it only results in a bit of slip between the blade and the shaft. I have not tried adding a bit of heat yet since I don't want to damage the shaft or nut.

Thanks in advance.

Whitt


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## Live Oak (Dec 22, 2003)

Try soaking the bolt and nut/fastener with LOTS of kroil or PB Blaster or a good quality penetrating lubricant. Best to let it soak in for several hours or more. 

If you can get an impact wrench into this mix, it may help to break the frozen bolt loose. 

Sometimes a moderate amount of heat may help but be very careful NOT to apply too much as you can destroy the temper of the steel in the blade. Using a heat gun vs. a torch is the safest bet although kinda slow.


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## chrpmaster (May 5, 2004)

When I remove the blade on my mower I always put a scrap piece of 2x4 in the path of the blade to keep it from spinning. Then I put a pipe wrench on the nut and go for it. These things are tough so don't be afraid to take a hammer to the wrench if it doesn't move.

Some of the newer models had a square hole in the bottom of the shaft that was the same size as a 3/8" ratchet. Then (in theory) you could push up with the ratchet and down with the wrench on the nut to take the blade off. But if they were really stuck the block of wood worked better for me.

I wouldn't use heat or you will cook the oil seal on the bottom of the shaft. That keeps the gear oil in the gearbox from leaking out. 

If its really stuck or I am in a hurry I will just use an angle grinder to sharpen the blade while its still on the mower. If you are mowing heavy grass and brush you will quickly nick up the blade anyhow. 

The 106 mower is the best 30" Gravely made. Some of the earlier 4 bolt decks had issues with cracking gear cases and decks near the bolt holes. 

Good luck and enjoy your "new" Gravely

Andy


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## Error401 (Jun 16, 2009)

Thanks guys. I'll give this another go here in a little bit. I did get a 1-7/16" impact socket and a ratchet to match, but I'll have to wait a bit to get an impact wrench to drive it. 

Heat was going to be my option of absolute last resort. 

The head itself is kind of strange. It has the word "Model" in reased letters, but no "106", but it looks exactly like a 106. Maybe just a fluke. A worn out blade I found in the shop has a round hole though, and the last time I looked the shaft did not have a square hole for the wrench you mentioned. The deck has six bolts. So I'm pretty sure it's a 106.

And I finally got the s/n, J-50762. Looks like it's mid to late 1969, just a year younger than me. I'll still call it new, even though it's been a lifelong friend (I remember driving it as a kid).

Whitt


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## Error401 (Jun 16, 2009)

I tried the block trick, but the grip the nut had on the threads exceeded the grip the washers had to the blade. I also tried cracking it loose using a hammer on the wrench with similar results.

So, I found a Hitachi WR22SA impact wrench we had on the shelf here at work and test drove it on the deck. It ended up being kind of anti climactic. That wrench is a beast. I think the hammer hit all of three times and it was off. I just have to find a good reason to justify buying one of those WR22SA's (way too much impact wrench for what I need).

As a side note, I picked up a C8 parts tractor back on the 3rd, and have transferred the governor and 8spd diff to mine. All I can say is wow, much nicer to run now. 

Thanks for the help.

Whitt


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## Cannuck-elhead (Feb 25, 2009)

BTW, rather than buying a big impact gun (read big $$$$) try a small cheap air chisel. They can usually be had for well under $100.

After soaking the bolt with penetrating oil as the ole' Chief mentioned, use a drill to make a dimple in the center of the head, then give er' heck with the air chisel for a minute.

Between the oil and the vibration I've had good luck with lots of nasty old bolts.

It also works really good on sticky carburetors too but you have to turn the air down to almost nothing. That will stop a stuck float leaking down in seconds.


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