MS 460 Broken Crankshaft

[MISteve]

Needed to pull the flywheel to replace seal. Usually drive a screwdriver in behind the flywheel and tap on the shaft. Been working for me on the 40 other saw rebuilds I have done. Was not sure if I should on the plastic/poly flywheel, so I went to the Stihl doc to have him remove it. I did not have the p/c on it when I brought it in. He tried to remove it with a puller and impact gun. Could not get it done, said he really needed the p/c on. I wanted to buy a puller anyway, so he sold the puller to me and left it on the saw. Took it home, did not feel like putting the p/c back on, so I used an adjustable wrench to hold the larger bolt and hit the pressing bolt with my impact gun. One quick hit with the impact and it came loose. Only problem is the nut and threaded end of the crankshaft broke off. First time I try the right tool and I destroy my first crank. Any idea why it broke? I have been using the impact gun to remove/ install clutches and flywheel bolts on 40 or more saws and no damage yet.

 

[Saw Dr.]

You don't leave the nut on with that puller....

 

[MISteve]

Thanks for the reply. The Stihl mechanic set the puller that way. I will go see him this morning and see what he has to say.

 

[chadihman]

( 1 ) Remove the flywheel nut from the crank. (2) thread the puller into into the flywheel. (3) thread the center bolt down against the crank. (4) hold the puller with a wrench while turning the center puller bolt don with another wrench. I never had to use an impact with a puller and the piston and cylinder installed should have nothing to do with it.

Was the flywheel nut still on the crank??????

 

[MISteve]

yes, the Stihl mechanic left the nut on the crank.

 

[chadihman]

Thanks for the reply. The Stihl mechanic set the puller that way. I will go see him this morning and see what he has to say.

Yeah Man he owes you a crank. I really would have thought the flywheel would have broken or the threads would have pulled from the flywheel. Seems to me like the crank shouldnt have had an stress even if the nut was left on.

 

[MISteve]

Thanks.

 

[sefh3]

I'm interested to see what the doc has to say. Why they left the nut on is beyond me. You are fighting against each other.

 

[MISteve]

Just got off the phone with the Stihl mechanic. Says he did not look to see if the nut was on, figured I had taken it off. Says he will get me a new crankshaft. Says they are about $250. I asked if he had any lower ends with good crank, bearings and good seals. He does not at this time. He says if I can find a good lower end for that he would pay for it. Pretty sure I know where to find one.

 

[sefh3]

PM me if your in need of one.

 

[HuskStihl]

That sounds like a very honorable guy

 

[MISteve]

He is good people. He thought I had removed the nut, he did not look. Said he would not think the puller will fit over the nut. It goes around the hex but does not clear the flange on the nut, easy to see why it broke.

 

[komatsuvarna]

Holy moly! You'd think he'd noticed something was up! It doesn't take but maybe half a turn with a wrench and the flywheel usually falls off in your hand. At least he wants to make it right.

 

[Naked Arborist]

We all make mistakes. This is what separates the men from the boys. You have a great mechanic !!!

Happy New Year

 

[MISteve]

I do my own rebuilds and repairs, but sometimes I need his help.

 

[Big_Wood]

man. talk about honorable. there's no chance a dealer here would ever own up to that mistake. they would just say as soon as it left the shop it wasn't my responsibility anymore.