How To Remove Froze Blade Mounting Base.. 1992 - 680540

rarebear

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
I bought a Lawn Boy 680540 in 1992 and over the years I have tried a few times to remove this flange to clean the muffler with no success..
I have worked as a machinist for over 40 year so I know mechanics and metal...
I have only used this machine to trim around trees and getting pissed I can't get this off..

I have tried two pry bars and tapping the shaft with a hammer, tapping the flange and today I added some heat and then dosed it in water as I thought about the bottom seal getting hot..

Should I buy a Gear Puller or try cutting flange in two with a zip wheel and or sawzall and buy a new flange..
Is there so trick I missed on the net other than puller?

Thanks..
 

jp1961

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
My LawnBoy mechanics handbook says to "strike the collar on it's edge, not on the top surface to prevent damage. A bent collar can cause severe blade vibration. Use a soft hammer to remove the collar."

Also tap the collar in the direction of rotation.

I would also try some Liquid Wrench and heat if she's that frozen.

Jeff
 

lewb

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
My guess is the collar slipped and basically welded it self to the shaft. I am a snowmobiler and this is a common problem with the a drive clutch. I have learned over the years to properly torque the bolt and not apply any anti-seize. If you use anti-seize you run the risk of the collar slipping and welding itself to the shaft. Need to use scotchbrite or emery cloth to take any rust off. One trick is to apply a thin layer of grease on top of the collar after you have is bolted in place. Rust will usually start at the top of the collar, the grease prevents the rust from getting into the top of the collar.

I would say your plan b would be using a cutoff wheel. If you nick the taper I would not think that will be the end of the world. Using penetrating oil and a hammer should get it to pop off.
 

motoman

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
LIquid wrench all 'round. Strike with soft hammer all around edge. Let sit overnite, Repeat. Repeat. As you know you are attacking the crystal interface which has "welded" the pieces together via corrosion.
 

SeniorCitizen

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
Use 2 hammers opposite simultaneously on the stuck round portion to distort the sleeve and break the bond that's been created over the years. Tap, tap tap in several locations around it.
 

beg

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
I used a puller and got it off however the collar was bent all to hell but it can be pounded back into shape somewhat.It may throw things out of balance but even with the few imperfections my mower did not vibrate.Liquid wrench? no pb blaster seems to be a better product.You may end up buying a collar or looking for a free parts mower.
 

Phototone

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
Flanges are cheap and readily available. I just use a puller, which destroys the flange.
 

Two-Stroke

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
:mad: I've had this problem. :mad:

I even made a puller out of a piece of angle iron and a couple of bolts. This rigged-up puller can put huge pressure on the blade mount -- but the angle iron bent while the blade mount stayed put. :confused2:

Phototone correctly pointed out that replacement mounts aren't expensive so it's no big deal to destroy one. Just be careful not to damage the shaft.
 

rarebear

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  • / How To Remove Froze Blade Mounting Base.. 1992 - 680540
I'm glade you all said use Liquid Wrench (penetrating oil) I don't know how many times I read folks saying use WD-40 (anti-rust oil)
The very best penetrating oil is KROIL by Kano Labs, in a spray can called Aero Kroil
The down side is you have to buy it direct from Kano..
Penetrating-Lubricating Oils

I ordered a gear puller off Amazon and should have it tomorrow or Monday
I will try the side persuasion method first as some suggested..
I was thinking it was keyed to the shaft even thought the manual doesn't show one.. :)

Thanks you all for the feedback..

PS Kano deal: Google Deal
 
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