So this is a question that I have asked and had answered previously, but yesterday three people failed to get the blade off a troy-bilt 42 inch riding mower. Just so I know for sure which way I should be turning. The mower deck is still attached to the mower. Working on the “passenger side” blade I am attempting to loosen the nut by pulling from front to back. Is this correct.
Looking at the blade from the bottom up (as if the mower were upside-down) determine which way it turns when cutting by noticing the pitch (angle) of the blades. They will be similar to an airplane’s prop in the way that they ‘cut’. Whichever way that is, to remove them you’ll turn the nut in the *opposite *direction. IOW, again from the bottom, if the blade cuts clockwise it’s a normal thread, counter-clockwise it’s left-handed (it’s always ‘tightening’ when cutting).
also wire brush the nut and spindle (bolt) to get all the grass/dirt off.
So I did use a wire brush as well as wd40 on the nut and spindle, so far to no avail.
Also, there is a little up and down play when I wiggle the blade. Does this suggest anything?
As a proxy to pitch, which I do not know how to describe, should it be loosened by turning AWAY from cutting edge, or toward the cutting edge?
it suggests that the blade is loose because it wasn’t tightened/is worn/ something is broken.
Right. I thought that it was conceivable that one could explain the wiggle and my inability to loosen the nut with a single explanation. Loose does not work, as the nut could not be tighter. Broken or worn seem likely.
Last time I changed a mower blade, the nut was on there super tight. I had to use a long-handled socket wrench and chock the blade (trying to hold the blade with one hand while turning the nut with the other isn’t gonna work).
Impact wrench/hammer
Up & down is a worn spindle
Yeah, so the things I unsuccessfully tried were: WF-40, breaker bar, foot long 2 x 4 fed through the grass chute and imobilizing the blade, taking up all the slack and tapping the wrench with hammer, hitting the wrench with a hammer, swinging a 12 pound maul like a golf club to hit the end of the wrench.
Get your 1/2" socket and a beater bar - hitting it with a hammer wont help - you need slow easy leverage in the right direction.
You said you tried a breaker bar - last time I had this issue, I took a 3’ length of pipe in order to gain the leverage I needed.
WD-40 is useless as a penetrating oil, it isn’t designed for that or effective at all. WD stands for water displacement.
Go to a hardware or automotive store and get a real penetrating oil. I prefer PB Blaster.
Have you tried heating it up with a torch?
I did not try the torch idea, and I have wanted to buy one anyway, so that might be worth looking into. How quick do you have to be to take advantage of the expansion differential?
FYI - Troy Built is a division of MTD as of 2001. My 42" lawn tractor is also manufactured by an MTD company and there are no left-handed threads on my mower.
I’ve never had any major difficulty removing the blades and can do it while holding the blade with one hand and heaving on the wrench/ratchet with the other hand.
20 to 30 seconds of heat, test the nut, and then repeat. Multiple heating and cooling cycles might help break things up. Just don’t overdo it to the point of making it red hot, it might make it brittle.
I have a similar Toro deck. When the deck is removed and you are looking at the blade from the bottom or underside, the normal “righty tighty, lefty loosey” rule applies.
Get a socket that fits the nut. Find a 3 foot pipe that fits the handle. Immobilize the blade with either a chunk of 2x4 or a blade lock. Now, heat the nut for 30 seconds or so and then pop it off. Chance are the wiggle you mentioned is because the little nubbins on the shaft spindle that the blade mates with are worn down. The spindle can be replaced but it’s a bitch.
Definitely try penetrating oil. I wouldn’t call WD-40 “useless” for that, but it’s certainly not the best.
I’ve always managed to loosen the nut by setting the wrench nearly (but not quite) parallel to the blade and “pinching”. That is, grabbing both the blade and wrench handle in both hands, and squeezing. This eliminates the need to block the blade from turning, and puts all of your strength directly in the right direction. Furthermore, even we lightweights can apply a lot of force this way.
What I don’t remember is whether I had to squeeze the back side of the blade or the “sharp” side. I put “sharp” in quotes, because when I’ve taken the blade off, it’s usually pretty dull. In any case, gloves can help.
or the blade was seated on top of the nubbins instead of mated with them and then the blade was later moved during use to the mating position.
Just wanted to say that I’m reading this with interest. I’ve got a totally different kind of mower, but similar problem. Now I’ve got some ideas to try out this weekend.