BENT SHAFT: 3.5 horsepower Briggs & Stratton has a bent shaft.

[Richard Milhous]

Guys, I like to fix things, which is why I am here and not reading reviews on Lowe's.com .......I enjoy the challenge and opportunity to learn something new.

Good for you. It's easier and often cheaper in the short run to replace a thing or have someone else fix it, but if you never fix anything you will never learn anything and you will always be helpless and getting ripped off.

So remove the flywheel and check the flywheel key?

If the crank got bent, the flywheel key will usually be sheared. If it's not, most likely some idiot replaced it with a piece of hard steel or even JB Welded the flywheel on. If that's the case, you sure want to know it now.

 

[MowManWV]

Rich,

Thanks man. Frankly I'm a little surprised a lawn mower forum has members that suggest buying a new mower over fixing it. I thought the purpose for a forum was to help others fix stuff.

Got the mower for free.....enjoy the challenge.

Now that the remnants of Hurricane Ida blew through I have several yards to mow but after that I might try to dig into it. I'll remove the flywheel next and see what that key looks like.

If no member steps up with a shaft straightener, I will contact repair shops and see what they have to offer.

May gear up for a rebuild.

 

[ILENGINE]

Rich,

Thanks man. Frankly I'm a little surprised a lawn mower forum has members that suggest buying a new mower over fixing it. I thought the purpose for a forum was to help others fix stuff.

Got the mower for free.....enjoy the challenge.

Now that the remnants of Hurricane Ida blew through I have several yards to mow but after that I might try to dig into it. I'll remove the flywheel next and see what that key looks like.

If no member steps up with a shaft straightener, I will contact repair shops and see what they have to offer.

May gear up for a rebuild.

Because crankshaft straightening was very common, you can create stress fractures in the metal from fatigue that could later break and cause property damage and ;personal injury, and so it is recommended to just replace the crankshaft or replace the mower because people especially technicians and repair shops don't like getting sued for potentially millions of dollars.

 

[MowManWV]

I'd still straighten the thing. If it cuts off my leg, that's on me.
I'll sign any release anyone wants when it comes to that or any other risk I take.

 

[ILENGINE]

But even with the signed release the shop could still be liable if your crankshaft breaks and the blade cuts off your neighbors leg.

My liability insurance had to pay a claim a few years ago because a guy was cutting a tree down and when he pulled the saw out of the cut the chain came off and cut his fathers leg requiring 46 stitches that was standing next to him. My only liability was that I had handled the saw last before the accident. No fault was found on my part but they paid the claim as a no fault claim.

 

[Richard Milhous]

But even with the signed release the shop could still be liable if your crankshaft breaks and the blade cuts off your neighbors leg.

My liability insurance had to pay a claim a few years ago because a guy was cutting a tree down and when he pulled the saw out of the cut the chain came off and cut his fathers leg requiring 46 stitches that was standing next to him. My only liability was that I had handled the saw last before the accident. No fault was found on my part but they paid the claim as a no fault claim.

Holy aping ass monkey!!!! I'll be more careful about chain tension.

Crankshafts used to get straightened all the time, and I've used mowers with straightened cranks (have a suspicion I'm using one now). I never heard of one breaking, and I don't doubt one straightening is okay. But if it's been straightened before... how do you know? How many times? Could be a mess when that blade hits a stump.

 

[ILENGINE]

Holy aping ass monkey!!!! I'll be more careful about chain tension.

Crankshafts used to get straightened all the time, and I've used mowers with straightened cranks (have a suspicion I'm using one now). I never heard of one breaking, and I don't doubt one straightening is okay. But if it's been straightened before... how do you know? How many times? Could be a mess when that blade hits a stump.

Actually in this case it wasn't related to chain tension. The problem was a 20 inch narrow safety bar that allowed enough side flex to derail the chain if side pressure was exerted on the rear handle when felling. People tend to either push down on the rear handle or pull up on the handle when felling a tree. In this case while testing with an identical saw that caused the accident, I could put the nose of the bar on a chuck of wood and while holding the rear of the handle up with one finger could flex the bar about 1 to 1-1/2 inch just from the weight of the saw pressing down on the bar.

Worked on another saw years ago that the customer was complaining his new chain wouldn't cut straight. With that saw and a similar bar as the accident saw I could make it cut straight cuts with just normal rear handle pressure, but If I pulled up on the rear handle with extra force could flex the bar to make it cut crooked.

And I have seen two crankshafts shear off after being straightened. Don't know all the details behind them so could of been multiple straightens or something else at work.

 

[MowManWV]

I never put blame on anyone else if I can possibly put it on myself. If you'd like impressive examples of this, drop me a PM.

Bring on the shaft straightener!

 

[MowManWV]

Found this video.....

Shaft straightening