Author Options:

Push-mower blade removal Answered

Heylo everybody! :)
I have a self-propelled mower that I am disassembling for a go-kart (probably). I've gotten everything off of it except for the engine. I know where the bolts are to take if off of the mower deck, but here's the problem: the blade won't come off.
I've blocked the blade in both directions and tried to loosen the middle bolt by turning both left and right, but the mower is pretty old and the shaft and bolt are probably rusted to craps. I also attempted shearing off the bolt with a crowbar and hammer, as well as cutting the head of the bolt off with a Sawzall.
The bolt dulled all the teeth on the metal blade for the Sawzall and dented the crowbar's edges.
So does anybody have any suggestions? I'm really at a loss on this one. I don't have access to a grinder or plasma cutter, which would seriously help out a lot. I was thinking about picking up a cold chisel from the store, but if I'm just being an idiot and turning in the wrong direction or something obvious, I'd rather know that than lop off a bolt and lose some of the hackability of the engine.
  - basementhacker


Hey everybody! My neighbor finally got it off. He had a nifty socket set that twists to lock the bolt in and he was able to finally get it out!

Thank you all for your help!

sometimes, heating the outer part , in this case, the shaft which the bolt threads into, with a torch will cause it to expand enough to let go. even a propane torch may be hot enough. combine this with penetrating oil, impact wrench, etc as necessary,

I don't have a propane torch... could a propane camping stove work? It would be a serious stretch...

perhaps you could borrow a torch. i dont thinkk theres harm in trying the stove, but its best to have heat one 1 small spot.

use a torch or impact driver. If still nothing, angle grinder, but that may render engine useless, unless you weld the next pulley in place.

I could definitely grind off the bolt. The pulley shown is, as far as I can tell, part of the shaft.

Yes & no. Correct, the pulley is part of the shaft, but once the bolt is removed, the whole pulley-shaft assembly should slide off. What is underneath is the actual bottom end of the engine crankshaft. You'll know, it should still be kinda shiny, with a groove running down the length and it is about 3/16" deep.

So I just need to keep spraying up around the bolt and wiggling it until it gets loose enough to move out?

pull the spark plug . clamp a block of wood to stop the blade. us a ratchet and socket it is reverse thread put a pipe on end of ratchet hit pipe with hammer to blot breaks loose. the pulley is held on with a wedge pin it will come off

Go to the store and pick up a can of PB blaster, it smells terrible but spray it on and let it soak. I used it to remove the O2 sensor on my wifes car. Came off real easy.

If you damage that shaft too much it will be useless in a gokart without a welder.

What does that stuff do? Dissolve the metal around the bolt?

I know... I do have access to a welder (and plasma cutter and angle grinder), but it's kind of spotty access right now.

Thank you!

its an oil with a penetrate in it, helps break the rust up and the oil penetrates the threads. Its good stuff, like 8 bucks a can. It will help you also in breaking down the engine once you get it removed.

If your sure of which way the bolt is supposed to thread you can try an impact wrench or maybe get lucky with a tire iron and just stomp on the tire iron.

Okay! Thanks! Do you know where I can get this stuff in suburban America? At the local Lowe's or Home Depot?

I had to sharpen my blades no long ago and faced a similar challenge.
As there is a screw it means it has to come apart the easy way....

Well not always.
First problem was the spinning direction of the blades, mine were spinning clockwise so the screw had a left thread.

Tried the brute force attack after soaking in oil over night but as you I had no luck at all.
Ended up using a rattle gun and should have tried that first.
What is good for the wheel nuts on your car is even better to remove those screws on lawn movers.

Well, I have one for the use on my car, but I am sure that every tyre centre will take that bolt off for you if you ask them nicely.
It is just a matter of right socket size and a simpe push of a button ;)
Manual mode with an impact driver is also an option, but in this case not easy as the blades need to fixed in place too.

soak it in wd40 or something similar. or hit it with a torch (before the wd40) to loosen it up. the bolt is likely just seized. it turns the same way a normal bolt would (leftie loosie rightie tightie). if you've blocked the blade from turning and you tried with a socket wrench and it didn't budge then that's probably what's wrong. if you can sufficiently immobilize the entire mower, and the blade you could get a long piece of pipe and use it as a cheater bar on the wrench (give me a long enough lever and I can move the earth.....or at least snap the head off of a bolt).

Okay... So I tried the big lever/Vise Grips combo. It didn't work.

I'm going to have to get my hands on a plasma cutter.

Which, I mean, I'm totally fine with... :D

I guess if you wanted to waste an afternoon you could just use a hack saw to cut the blade small enough to fit through the hole....pretty tough steel though

Yeah... I had plans for it though...

Thanks for your help! I'll keep working on it!

Oh, I used WD-40. Lots of it. :D

I haven't tried the pipe lever yet though. That's next. Another problem is that the wrench won't grip the bolt and slips off. I'm probably using Vise Grips this time.

Thanks for your help!