Push lawn mower crankshaft straightening?

General Off Topic
1

I hit the dang water main housing in the yard the other day and bent the crankshaft. Anyone know of any shops in the Charleston area that do that type of work? Mower is only 2 years old!:dizzy_face:

2

When I was much younger I worked on lawn mowers and small engines. Its very difficult to straighten a crank, and probably not worth it. A better idea would be to purchase a new crank shaft or dig one out of another matching motor that has other issues. If your motor even ran a second - like even 1/2 revolution - it could have damaged the cylinder walls , gear teeth or even bearings & seals. Its not the fall - Its the sudden stop that kills

3

^^^^^^what Natureboy said^^^^^^^^ unless you’ve got a reasonably new high dollar mower you can probably replace the entire machine cheaper than fixing the old one;;;; next best route imo would be to visit northern tool or tractor supply and purchase new one


George McDonald ; MAD Charleston
[http://www.militaryappreciationday.org

When you see “Old Glory” waving in the breeze, know that it is the dying breaths of our fallen hero’s that makes it wave.
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4

My brother ruined an almost new mower of mine running over a stump. I could buy a new mower for what it would have cost to repair.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?

5

I’ve done some damage to a few and seen a lot of damage to others, but a bent Crank? riding lawnmower or push. If a rider make sure it’s not just the pullies bent. If a push might just be the blade bent.

Anyway what natureboy said if it is bent. Not sure what engine you are running but look into a short block kit, maybe check ebay, and don’t rule out hitting up a local small engine repair shop for a used one? Sometimes they have some “scratch and dent” stuff out of the Orangeburg Husky plant.

“Why Bruce?”

6

Rarely do I take small engines in for service as I do a vast majority of my mower work myself, but Corky’s on James Island has always done me right. Parts or Service, they always been helpful. Corner of Folly and Camp.

Narcosis

7

I believe its the crankshaft. It is the rod the blade attaches to. I am fairly mechanical, but this job may be a little much for me and I can’t find any youtube videos on it how to replace it. There are some funny videos of people using hammers to straighten it out though! I will give Corky’s a call and see what they say. It is a push mower.

8

if the engine is locked up , then your problems are more than a bent crank

9

Its not locked up, starts right up and runs fine. Talked to a few shops and it appears the juice isn’t worth the squeeze. Going to straighten it as best I can with the heat and beat method and see how long she goes.

10
quote:
Originally posted by fishcrazy

Its not locked up, starts right up and runs fine. Talked to a few shops and it appears the juice isn’t worth the squeeze. Going to straighten it as best I can with the heat and beat method and see how long she goes.

Easy on the heat or you will burn the crank seal. but I’m still wondering about a bent Crank. I’ve never seen one successfully straightened
 don’t know how you would?

Shoot us a picture and brand of engine
 you said where the blade hooks up so I’m assuming a push lawnmower?

If it’s running I’d run it till it dies. Keep an eye out on the oil level because if it is a bent crank it will probably wipe the crank seal and start leaking oil.

Good Luck!

“Why Bruce?”

11

Look in Northern tool you can order the same motor and keep damaged motor for parts

12

Wait a minute - If the engine runs fine, what leads you to believe that the shaft is bent? Its possible to bend the shaft between the engine block and the blade , but the vibration would beat the engine to death and the lower oil seal will be torn up . ??? Are you sure its not a bent blade? Very common. Most lawn mowers are made with a slip fit blade to save the shaft. What ever you do = don’t hammer on the lower shaft. That’s a sure way to crack the block!

13

Natureboy that is the area I am talking about and it vibrated pretty good even with a new blade. You could see the bend when looking at the shaft and slowly pulling the cord. It’s just a slight bend but it vibrates more than it should. Took it to a small engine shop on Johns island and they straightened it for $40, didn’t ask how though. Maybe they pulled one on me, but it doesn’t vibrate as bad and I didn’t work on it and make it worse
which often happens :smiley:. Thanks for all of he responses.

14

I’m sure there are some lessons in here, I just don’t know what they are

15
quote:
Originally posted by PeaPod

I’m sure there are some lessons in here, I just don’t know what they are

Old guys with a bent shaft looking for a quick fix, so the can get back to "mowing"... I just don't see an innuendo there... $40 isn't that bad of a deal to get you back in action with a straight hard shaft that can turn a few RPMs...
16

I bent one on a dogwood stump. New mower, just Briggs & Straton motor. Took it to an old guy in the country. Seems like he removed the motor from the frame and put it on a jig where the shaft was in a 90 degree template thingy. Turned the shaft to see where the bend was and kept leaning on it with a heavy pipe until it was close. Still runs and that was twenty years ago. Always thought it has a little extra vibration to it but he only charged me like $30.00 and it still runs good. Good luck wid dat!

Keep your nose in the wind and your eyes along the skyline.

17

I bent the prop shaft on my 25 merc years ago and used a 10’ length of pipe to straten it out, has run well with out a quiver or leaking seal! Some time I get lucky!