Hope I didn't mess up anything

[Keithandstef]

I was changing out the sprocket on my saw and used a metal piston stop to hold the piston steady. I accidentally turned the wrench the wrong way for the tiniest amount actually tightening the clutch more. It came off fine when I went the correct direction. Runs fine. Is it likely I bent anything? Piston rod or drive shaft?

Thanks.

 

[Marshy]

Doubtful, you'd know immediately when running it.

 

[HarleyT]

Should be fine.

 

[Keithandstef]

Doubtful, you'd know immediately when running it.

True. If the piston rod were bent it would be a mess I bet.

 

[HarleyT]

Ms170/180?
We have seen that one bent....

 

[Keithandstef]

Husky 257.

 

[HarleyT]

From another thread.....

 

[Full Chisel]

I have heard of bent 210/211 rods from pulling one over that was hydrolocked.

I'm sure you're fine.

 

[alexcagle]

unrelated ship Whoops.....

The only time a metal piston stop did any damage was to a piston that the plug was angled in relation to the cylinder bore. Luckily it was on tear down, and the piston was a gonner anyways.

 

[Keithandstef]

View attachment 510896 unrelated ship Whoops.....

The only time a metal piston stop did any damage was to a piston that the plug was angled in relation to the cylinder bore. Luckily it was on tear down, and the piston was a gonner anyways.

Well, mine is at a slight angle I think. The spark plug hole is off angle to the top of the cylinder. I probably don't understand the geometry of what you're saying (I'm learning the hard way). The saw runs fine so I bet no damage done.

 

[Keithandstef]

From another thread.....

View attachment 510859

So how would a saw run if the piston rod were even slightly bent? Compression would be shot at a minimum?

 

[rd35]

Depends on what you mean by "slightly". If the piston skirt does not hit the crank, then, at worst, port timing would be a tad off and it would likely run a little weak and sluggish. If the rod is only slightly tweaked, you might not even be able to detect it and would never know.

 

[Keithandstef]

Well, my hope is that I just tightened the clutch on the spindle itself. I hope I hope.

 

[sunfish]

Husky 257.

I never use a piston stop on a Husky. Just use the little notches on the clutch to knock it off.

 

[CascadeHusky]

I never use a piston stop on a Husky. Just use the little notches on the clutch to known it off.

I dont think this is a great option for a 257...but they do have a handy place to affix a socket. (Btw, I'm of the opinion any impact wrench problems are user error...such as a stop and impact)

OP, for a piston stop use that piece of nylon cord you have sitting on your bench. If there isn't one there, I guarantee that you have a section in close proximity to ANY saw you own that starts...at all times. Just fold and go.

If you must use a piston stop...get a plastic one.

 

[rd35]

CascadeHusky brings up a good point about which I must ask a question (this has been on my mind for some time now). The use of rope as a piston stop seems risky to me. My concern is that in the event one inserts some amount of rope through the plug hole...just how much rope should you put in there? It seems to me that if you don't insert enough rope to stop the crank at near 90 degrees before top-dead-center, then the compressive stress on the rod might become very very high as torque is applied to the crank to loosen or tighten the clutch or the flywheel nut. Has anybody out there ever bent a rod using rope for a piston stop? My concern may be invalid, but it still is a concern to me.

 

[rd35]

Another concern (and this actually happened to me once) is when the rope gets pinched in a port. Can the rope cause so much twist on the piston to damage a skirt?

 

[HarleyT]

CascadeHusky brings up a good point about which I must ask a question (this has been on my mind for some time now). The use of rope as a piston stop seems risky to me. My concern is that in the event one inserts some amount of rope through the plug hole...just how much rope should you put in there? It seems to me that if you don't insert enough rope to stop the crank at near 90 degrees before top-dead-center, then the compressive stress on the rod might become very very high as torque is applied to the crank to loosen or tighten the clutch or the flywheel nut. Has anybody out there ever bent a rod using rope for a piston stop? My concern may be invalid, but it still is a concern to me.

Yes.

http://www.arboristsite.com/community/threads/piston-stop.186067/

 

[spudulike]

So how would a saw run if the piston rod were even slightly bent? Compression would be shot at a minimum?

Vibration and then loss of compression and power as the piston scuffs the cylinder due to not being aligned with the bore correctly. Eventually you will be through the plating - seen it before with bent rods and twisted cranks.

 

[Big Block]

the chainsawguy uses a length of starter rope stuffed in the spark plug hole