Bush Hog Help

[piperc744]

hey guys, ive got a little problem with my mower attachment, its a 5 ft. bush hog. the problem is that the bolts that my two lower arms attach to, keep falling off.... when i got the 2005 tractor recently (used), it had bolts on there and neither of them were tightened fully, and could not tighten fully, because they were stripped, no threads basically....

so i went and got 2 new ones of same size, except these were not the forged ones, it had the big nut and a skinnier nut on the other end instead of the forged stopper.

now first time using it on the job... and what do u know, 2 hrs into mowing, one arm is loose, the nut missing. i managed to secure it loosely back by using the skinny nut where the forged piece usually is, and on the outside part i just used the lynch pin to hold it all in place. if u can picture that? but slowly, maybe a single thread per 10 minutes, the skinny nut began to strip its way down till it was completely off as well, i had to finish the job with one arm off... not good....

what am i doing wrong, what kind of metal would prevent this, i cannot have this happen at every job, did i tighten too much? i used a large pipe wrench and tightened them almost as much as i can, but did not want to tighten too much as i felt this would cause the threads to stretch or what not....

i think it may have something to do with the horizontal play in my lower arms, should i have them tighter? should the mower be able to sway left or right a little, or none at all? how should i run my top link? long, short, or in the middle?

any advice at all is much appreciated as i am starting a business and cannot have these problems.... also any other tips u guys have for a field mowing and cutter attachments is much appreciated as well.

thanks
chris

 

[tungularafishcamp]

I like to keep my lower link arms snug so there is no wiggle room and I would put red loctite on the nuts, lotsa vibration with a brush hog u will need heat to take the pins off again tho. Happy hoggin,
Rick

 

[kebo]

Maybe your bush hog has a serious vibration problem? Like maybe a blade imbalance or something??

 

[piperc744]

ok, loctite sounds like a great idea, ill grab some while im in town today.

how much do u tighten the bolts there, like i said i used a large pipe wrench and did it pretty tight, but not going hulk on it or nething. should i be using impact sockets???

also, ive never been under the cutter yet, gonna need to very soon, wanna sharpen blades, probably need good balancing, and sometimes when i engage the pto at 540, it jumps a little to get going, is this normal? doesnt seem harmful...

also, how do u guys go about getting to ur blades, should i use the 3pt to lift it, kill the engine, and just climb under, maybe a couple jack stands for safety?

i was told not to take the blades off unless u can torque them back on properly and most people go to a shop? is this necessary in ur opinion? id like to lift it and just take a hand grinder to it, but also know every now and again like at least once a season it should be removed and re torqued.

thanks,
chris

 

[piperc744]

oh and one more thing, what about the top link for the 3 pt. is it supposed to be long short or medium? right now ive got it set up for when i was using my box scraper and the link is short. i feel like the cutter is a little elevated closest to the tractor where it hooks up. so probably needs to be longer, but gimme some ball park ranges to deal with then i can tweak it from there.

thanks again,
chris

 

[CharlieS]

ok, loctite sounds like a great idea, ill grab some while im in town today.

how much do u tighten the bolts there, like i said i used a large pipe wrench and did it pretty tight, but not going hulk on it or nething. should i be using impact sockets???

also, ive never been under the cutter yet, gonna need to very soon, wanna sharpen blades, probably need good balancing, and sometimes when i engage the pto at 540, it jumps a little to get going, is this normal? doesnt seem harmful...

also, how do u guys go about getting to ur blades, should i use the 3pt to lift it, kill the engine, and just climb under, maybe a couple jack stands for safety?

i was told not to take the blades off unless u can torque them back on properly and most people go to a shop? is this necessary in ur opinion? id like to lift it and just take a hand grinder to it, but also know every now and again like at least once a season it should be removed and re torqued.

thanks,
chris

Loctite is one solution or you can always pick up two more nuts of the appropriate size and double nut the pins to prevent the nuts from backing off.
My personal preference is to double nut,with a lock washer between the firt nut and frame of course.
Mainly the reason i double nut vibration prone bolts, (or in this case pins) i anti-sieze the threads, because sooner or later i'll need to remove them. As far as torque, i don't use a torque wrench, but i'll crank on them as tight as i can get with a 3/4 socket set and about a 3 foot cheater.

To remove blades for sharpening, we usually take the cutter off the three point, and lift one end of it with the loader so its standing vertically. Safety block it with an 8' 4x4 and i can stand up to remove the knives for sharpening.
Lifting with the three point can be done too if you use jack stands or similar for safety supports, but that means crawling under the mower deck and takes two people to remove/replace the knives.
I don't torque the blade pivot bolts either, as they are a shouldered bolt so you can't tighten them enough to bind the blades. I know from experience how much effort it took to loosen them when the bushhog was new so i can apply about the same amount of force when remounting the knives. I also antiseize the threads on the blade bolts and just use the lockwasher and nut supplied as oem. never had one come loose after tightening it with the same 3/4" breaker bar and appropriate sized socket using the same 3' cheater.

You also mention "when you engage the pto @ 540" I hope your not saying you throw the pto in gear with the engine tach'd up to 540 pto speed.
Thats not a good thing. dumping all that horsepower and resistance to the pto at full speed breaks things. it could damage the pto, the cutter gearbox and lots of other things.
The proper and safe way to engage the pto is with the tractor at idle speed, and the tool close to the ground, this minimizes the shock load to all tractor and mower components.

 

[CharlieS]

oh and one more thing, what about the top link for the 3 pt. is it supposed to be long short or medium? right now ive got it set up for when i was using my box scraper and the link is short. i feel like the cutter is a little elevated closest to the tractor where it hooks up. so probably needs to be longer, but gimme some ball park ranges to deal with then i can tweak it from there.

thanks again,
chris

Length of the toplink isn't as critical as setting the proper adjustment length, which depends on mower settings. you adjust the dolly wheel to the chosen height then adjust the toplink so the front of the mower deck is one or two inches lower than the rear. The only concern about toplink length is you have a toplink with adiquate adjustment range.

 

[clemsonfor]

You can double nut like others have said or locktight, but crank them down as hard as you can. There usually grade 8 anyway i think, or at least just painted gold? Your using a lock washer right? You can also tack weld them on, you may have to cut it off when you have to or burn it out but what are the chances you will ever touch the lift pin again, if so will just take 15 more mins with a grinder.

Yes lift the hog up and onto jackstands to get under it. Whoever told you a shop has to remove for balance alignment is an idiot. there just like a lawnmower blade except attached at one end. You take your own mower blade off right? These things can come loose as well. I replaced my seal on the bottom and the nuts were finger loose after a year and a half. You tighten this stuff as hard as you can. There like over 1" nuts they can take some torque.