He-Man has a bent rod

[ranchcutter]

It started innocently enough: I wanted to pull the clutch on my Stihl MS 210 and check the worm drive on the oil pump. Pull the spark plug, push nylon rope in the hole, left hand thread on the clutch, piece of cake. As I pull on the wrench the crank rotates a bit and stops, the clutch still tight. Pull out the rope and rotate the crank, it now rotates less than 180 degrees with a nice metallic clank at each end. I quickly realize it's not cake I'm eating. After a complete tear down the self-inflicted problem is obvious.

Does anybody know of a source of a used crankshaft/rod with a dual counterweight (1123 030 0411)?

 

[outdoorlivin247]

Just getting a front row seat...opcorn:

 

[mtngun]

Darned. :msp_mad:

You're not the first, I think Brad bent a con rod on a small Stihl a few years back.

I'm wondering if it isn't safer to use a rattle gun ? Of course, some people say the opposite is true. :msp_confused:

 

[Steveo_supremo]

Wow! If I hadn't seen it I would never believe you could bend a rod like that trying to remove a clutch. Even if a guy was trying to turn it the wrong way You'd think the threaded end of the crank would twist off before it bent the rod.

 

[timberwolf]

I'd go with the gun, thinking of it that the gun works partly against the inertia of the crank mass, that cut some force off the rod. The next point with impact is that it is compressing the engine with piston against nothing but air air so the force should never exceed normal engine forces and they will be balanced unlike a rope stuffed in the bore which may side load the piston.

Also air impact is in direct line with the crank, go at it with a wrench or socket and bar and there will be sideways forces on the crank which can bend cranks.

If you need to go the roap method, use lots enough that the piston is nearly down to the exhaust port, will reduce load on the rod.

 

[MnSam]

Don't feel bad, you aren't alone.

http://www.arboristsite.com/chainsaw/167364.htm

 

[barneyrb]

That is the 3rd or 4th little POS Stihl that's done that. I sent a rod out a month or so ago that wouldn't work on his saw.

Yeah they make the greatest saw in the world....

 

[MnSam]

Yeah, and I can send it along to ranchcutter if he thinks it will work for him. Thanks again barneyb for trying to help by the way. Maybe I should send it to ranchcutter anyway, kind of a passing the torch kind of thing.

 

[barneyrb]

Yeah, and I can send it along to ranchcutter if he thinks it will work for him. Thanks again barneyb for trying to help by the way. Maybe I should send it to ranchcutter anyway, kind of a passing the torch kind of thing.

LOL....is that a torch you really want to pass??????? I didn't remember who I sent that too, sorry it didn't work out but that is the wimpiest rod I'd ever seen.

 

[openloop]

just an observation... but if the piston is stopped by the rope near TDC or BDC, when torque is applied to the crank I think the amount of force that is directed into the rod is amplified. When you jam the piston it should be stopped at mid bore to ensure the mechanical advantage is at its lowest.

Where do the screw in piston stops stop the piston?

 

[wheelman]

Dont put in too much rope piston could end up below the transfers and chop off a bit of rope. I use an impact wrench personally and have never had a problem.

 

[a. palmer jr.]

On my 021 the rod is replaceable..doesn't look like it is on that one.

 

[Saw Dr.]

just an observation... but if the piston is stopped by the rope near TDC or BDC, when torque is applied to the crank I think the amount of force that is directed into the rod is amplified. When you jam the piston it should be stopped at mid bore to ensure the mechanical advantage is at its lowest.

Where do the screw in piston stops stop the piston?

Well well, a fine answer to one of my favorite topics. Y'all knew I could not stay sidelined for long.

 

[bobt]

We always simply used the impact wrench,,,,,,,but what about these aluminum flywheels with the built in keys. Back in the 70's when we were using the impact, all the flywheels had steel woodruff keys. I would worry about shearing off the keys unless the flywheel was removed.

Bob

 

[a. palmer jr.]

We always simply used the impact wrench,,,,,,,but what about these aluminum flywheels with the built in keys. Back in the 70's when we were using the impact, all the flywheels had steel woodruff keys. I would worry about shearing off the keys unless the flywheel was removed.

Bob

I thought it was bad when some of the cheaper weed trimmers and chainsaws did that, now even more expensive saws have the built in key.

 

[openloop]

We always simply used the impact wrench,,,,,,,but what about these aluminum flywheels with the built in keys. Back in the 70's when we were using the impact, all the flywheels had steel woodruff keys. I would worry about shearing off the keys unless the flywheel was removed.

Bob

If the nut holding the flywheel is tight then there shouldnt be any load on the key...the nut, crank, and flywheel all move in unison until the nut is loosened, and any taper is unlocked. Once the nut is loosened the impact gun no longer imparts any torque into the crank, so shearing the key should prove difficult.

 

[bobt]

If the nut holding the flywheel is tight then there shouldnt be any load on the key...the nut, crank, and flywheel all move in unison until the nut is loosened, and any taper is unlocked. Once the nut is loosened the impact gun no longer imparts any torque into the crank, so shearing the key should prove difficult.

What you said makes sense. I have never done it with an aluminum key, and that is why I said what I did. I keep reading here on AS about pistons being punctured by metal piston stops, and connecting rods being bent using the rope method.

How about using these plastic stops that are bent and have a small knob on the end. They are not screwed in, but simply placed in the sparkplug hole between the top of the piston and cylinder. Seems like it would be the same as the rope method.

Then I hear that when removing clutches,,,,,the trick is to apply even steady pressure, and not reef on it to break it loose. What's best?

Bob

 

[Justsaws]

It took an average of 5 rounds of removing a clutch and reinstalling it on 017/018 Stihls to break the flywheel loose while using an impact on the clutch. The flywheels were supposedly at Stihl's specs. I did not do those.

Three different saws with multiple times though the test. Very boring test.

Sparkplug in.

There was no other damage.

Safest bet is to remove the flywheel first if you care about the key and are uncertain about the flywheels torque/condition.

Test was done to settle a mild dispute.

Becareful settling disputes or you might end up with a bunch of 017/018 flywheels without keys and probably an 017.

Lots of damaged pistons and rods from those that fear impact wrenchs.

 

[bobt]

It took an average of 5 rounds of removing a clutch and reinstalling it on 017/018 Stihls to break the flywheel loose while using an impact on the clutch. The flywheels were supposedly at Stihl's specs. I did not do those.

Three different saws with multiple times though the test. Very boring test.

Sparkplug in.

There was no other damage.

Safest bet is to remove the flywheel first if you care about the key and are uncertain about the flywheels torque/condition.

Test was done to settle a mild dispute.

Becareful settling disputes or you might end up with a bunch of 017/018 flywheels without keys and probably an 017.

Lots of damaged pistons and rods from those that fear impact wrenchs.

Good test! I like the impact wrench with the sparkplug installed method. If I am worried about the flywheel key, remove the flywheel. Your tests confirm this.

 

[angelo c]

....opcorn:...just grabbing a seat here on the lawn ...waitin for the fireworks show to start