Help for a first time blade replacer?

cruzenmike

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You will see a ton of people using an "impact wrench" while changing their blades but this is NOT advised. A torque wrench should always be used to tighten the blades back down. Follow your manual for the torque spec and whether or not anti-seize on the bolt threads is needed. ALWAYS start your bolts by hand; once started you can switch to the torque wrench.

Why not use an impact wrench? Even a low voltage cordless impact wrench can exceed the torque rating and risk stripping the threads on your spindle shaft. A pneumatic impact wrench typically exceeds the torque of cordless ones.

While changing blades without an impact wrench is certainly more difficult and time consuming, it still can be done and done safely if directions are followed and precautions are taken.
 

logert gogert

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You will see a ton of people using an "impact wrench" while changing their blades but this is NOT advised. A torque wrench should always be used to tighten the blades back down. Follow your manual for the torque spec and whether or not anti-seize on the bolt threads is needed. ALWAYS start your bolts by hand; once started you can switch to the torque wrench.

Why not use an impact wrench? Even a low voltage cordless impact wrench can exceed the torque rating and risk stripping the threads on your spindle shaft. A pneumatic impact wrench typically exceeds the torque of cordless ones.

While changing blades without an impact wrench is certainly more difficult and time consuming, it still can be done and done safely if directions are followed and precautions are taken.
Yes, he is completely correct, I once changed the blades on my mower, and I didnt know any better, so i borrowed my dads corded impact ( the REALLY powerful ones that weigh like five pounds. I put the impact on the bolt, and it came out in about a second XD. i then replaced my blade, hand tightened the bolt, put the impact on it, and held the trigger for about 2-3 seconds i wanna say, the all of a sudden the blade fell.
I also noticed the bolt fell to, i examined the bolt, and turns out the bolt stripped! Half of the bolt was completely flat be cause of all the impact power!
luckily it didnt strip the crankshaft. i then went to my local small engine shop, and asked it they had a bolt like mine, ( i showed them the stripped bolt )
he said,
"impact do this?"

i said, "yep"

and i guess he could read my mind cause he said, "have you learned your lesson?"

"Learned my lesson on what?" i said.

"using an impact" he said.

i then said, " oh yes sir."

"You going to do it again?"

"No sir" i said

"3.27$" he said

i pulled out my wallet

he said, " oh, no need to pay i got it."

"no sir its fine, you dont have to do that." i said

he then said, " you want that bolt or not?"

"yes sir, i need that bolt." i said

he said, " then take it so you can go cut your grass."

"thank you, have a nice day." i said

"you to bud." he said

then right before i walked out the door, i looked back at him and he smiled then winked at me.
still cant really figure out why he gave it to me.
 

bertsmobile1

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You will see a ton of people using an "impact wrench" while changing their blades but this is NOT advised. A torque wrench should always be used to tighten the blades back down. Follow your manual for the torque spec and whether or not anti-seize on the bolt threads is needed. ALWAYS start your bolts by hand; once started you can switch to the torque wrench.

Why not use an impact wrench? Even a low voltage cordless impact wrench can exceed the torque rating and risk stripping the threads on your spindle shaft. A pneumatic impact wrench typically exceeds the torque of cordless ones.

While changing blades without an impact wrench is certainly more difficult and time consuming, it still can be done and done safely if directions are followed and precautions are taken.

Which is exactly why I advised getting an impact gun with multiple torque settings and installing on the lowest setting .
When fitting swing backs I always use a torque wrench because it is way too easy to overtighten them as they all have different torques from 10 ft lbs to 30 ft lbs.
However with bar blase the exact tension is not all that important
 

Mr. Mower

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If I try to run out and buy a torque wrench right now, is there a standar amount I need to look for for all mower blades or is that mower specific too?

Any basic type of torque wrench that can be found in a hardware or auto parts store is fine to use just as long as it has the ability to meet the specific torque value ratings such as 10-80 foot pounds or 20-110 foot pounds, etc.
 
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Hustler27

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I'm giving in guys. Thanks for trying to help. I managed to get a 5/8's around one of the three nuts and I can't get it to budge. I'm dragging the mowever off the of the car stands wrenching on it. Thanks.
 

logert gogert

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are you saying that the socket is stuck to the head of the bolt?
or is the bolt just not coming out?
 

bertsmobile1

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I'm giving in guys. Thanks for trying to help. I managed to get a 5/8's around one of the three nuts and I can't get it to budge. I'm dragging the mowever off the of the car stands wrenching on it. Thanks.
This is why we use impact guns to remove them. About 2 or 3 times a year I need to cut a head off because my impact can not shift them .
When you asked about tension wrenches it was drawn to your attention that these nuts & bolts self tighten in use .
For replacing them in the field I have a 8' length of hollow rectangular steel tube that I slop over the blades then a 3/4" drive breaker bar than is 5' long and another 4' of steam pipe.
The socket goes on the bolt with a jack under it to hold it on then I go the the ends of the tubes hold one with my arms the use my legs to push the other.
Good thing is being a big bolt they never break off and once loosened a single turn always come out with fingers .
Once you get yours off make it a habit to remove them at least once if not twice a season.
I always suggest customers buy at least one spare pair of blades to have on the shelf nice & sharp ready to fit and change them over every couple of months.
Not only do you get a better cut cause the blades are sharp you also can keep an eye on the wear so don't have a blade suddenly break apart .
You also get the check the spindle bearings ( if you slipped the belt off ) so again don't get caught out with a collapsed bearing that can do a lot of damage to the deck and housing.
 

Hustler27

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How do I make 100% I'm wrenching the correct direction?
 

Hustler27

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Yeah I don't have pipe or a breaker bar and this thing has been on here forever. Maybe this is why I have good intentions every year and then end up losing the battle. I've spent hours wrenching on it now.
 
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