Some echo come oem with 2 ears. I stay away from 2 ear aftermarket ones though and will not use them.
OEM echo
Piston circlip failure on Stihl 1127 series.
- Thread starter fearofpavement
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Some echo come oem with 2 ears. I stay away from 2 ear aftermarket ones though and will not use them.
OEM echo
LegDeLimber
Addicted to ArboristSite
Take a look at the radius in the two eared clips and the single eared ones
in wde_1978 #18 post.
Now take a look at the bend in the remaining clip in fearofpavement post #9, the last picture.
Nasty corner there huh! see that lump of displaced metal inside the bend?
FOP, If you don't mind, can you pop that clip and get a tight closeup of it?
Might want to shoot a frame down at it in the groove first too.
Also look at the other end of it and see if looks like any movement.
Is there any marking or scraping in the groove?
That tight corner where the cir-clip is *bent* vs having a nice curve, sort of tells the story to come, I'd wager.
Just for giggles, How close can you get the lens to the clip after removing it?
Be interesting to see how much the metal is pushed to the sides in the corner of the clip bend.
I'd throw the caliper or mic on it too.
As for removing the ears? Dont snap 'em off, use a cutting wheel in your twirly tool to nick 'em off.
Then dress the burr off so that you don't have it hang the clip up in the groove and not settle in to bottom of the groove.
It can also sit on the burr, depending on the direction , So the burr's gotta be removed.
IF you're concerned with removal later, just make a little notch in the side the clip groove before you install things and then you're good to go at removal time!
This piston looks like you could get the ring out with no problem though, as it has a cutout at the lower side already.
Don't forget to look at the clip after it's in place to see if it fits.
Make sure it has the same radius as the groove.
i.e. is sitting down in the groove , the same depth, all way around the hole.
in wde_1978 #18 post.
Now take a look at the bend in the remaining clip in fearofpavement post #9, the last picture.
Nasty corner there huh! see that lump of displaced metal inside the bend?
FOP, If you don't mind, can you pop that clip and get a tight closeup of it?
Might want to shoot a frame down at it in the groove first too.
Also look at the other end of it and see if looks like any movement.
Is there any marking or scraping in the groove?
That tight corner where the cir-clip is *bent* vs having a nice curve, sort of tells the story to come, I'd wager.
Just for giggles, How close can you get the lens to the clip after removing it?
Be interesting to see how much the metal is pushed to the sides in the corner of the clip bend.
I'd throw the caliper or mic on it too.
As for removing the ears? Dont snap 'em off, use a cutting wheel in your twirly tool to nick 'em off.
Then dress the burr off so that you don't have it hang the clip up in the groove and not settle in to bottom of the groove.
It can also sit on the burr, depending on the direction , So the burr's gotta be removed.
IF you're concerned with removal later, just make a little notch in the side the clip groove before you install things and then you're good to go at removal time!
This piston looks like you could get the ring out with no problem though, as it has a cutout at the lower side already.
Don't forget to look at the clip after it's in place to see if it fits.
Make sure it has the same radius as the groove.
i.e. is sitting down in the groove , the same depth, all way around the hole.
Philip Wheelock
Finis Origine Pendet
The OEM Stihl MS460 piston (below) has a gap in the circlip race where you can dig the old one out. The circlips have no ears, so there are no sharp bends or possibility of flexing failure. Press into the race by hand. Simpler is better; just one less thing to go wrong.
I have several C-clip installer tools ( Stihl-buxton ect) I will only use OEM clips. I have tried to use many clips with many tools to decide which was the best...IMO
the Stihl Clips are the best and will go in with either tools. and the OEMs will not with either. My finger tips are not what they used to be to use a screw driver or other "redneck method" of installing.
Go and try to install the 8mm clip in a MS200t and lemme know if the tool wasn't worth $50. Luckily the Stihl OEM pistons come with one clip installed already.
CrufflerJJ
ArboristSite Operative
Clever, those Germans!
tomdcoker
Addicted to ArboristSite
Some of the older (028 ) Stihl saws have 2 ears. I have no problem installing them but the later ones with no ears are a pain using the rednck method. Tom
Rx7man
Cattle Rubbing Post
I agree the remaining circlip has WAY too much ear on it.. if you have a set of good end-cutters you can possibly just clip the ear down a bit.
For peace of mind I'd probably look at saws in my possession and double check them before they leave.. for the ones that are out there.. well.. wait and see I guess. At this point you've had ONE failure, so it's not something to sweat too much blood over, but worthwhile to take future precautions.
I have a Farmertec top end in my Manhattan project "277".. It runs at 11-12,000 RPM in the cut and hasn't blown up yet (5-10 tanks).. It's actually surprising me
For peace of mind I'd probably look at saws in my possession and double check them before they leave.. for the ones that are out there.. well.. wait and see I guess. At this point you've had ONE failure, so it's not something to sweat too much blood over, but worthwhile to take future precautions.
I have a Farmertec top end in my Manhattan project "277".. It runs at 11-12,000 RPM in the cut and hasn't blown up yet (5-10 tanks).. It's actually surprising me
The piston of my spare OEM Dolmar PS-7900 P&C kit also features that gap, and an ear less circlip preinstaled.
stihlboy
Guess who's back
boy that saw got pissed off
Stihlofadeal64
Addicted to ArboristSite
So, if someone had one of the Hutzl kits already with these eared clips -- would it be safe to say it is not a good choice to use these clips? If so what are the options -- when I first joined the cir clip dilemma with aftermarket piston kits was pretty hot at that time.
I'm not sure I like popping the ear off if it leaves quite a bit less engagement in the circlip install pocket. (That may be however, the only option if you decide to make it work with what you have). What about the possibility of buying a Meteor piston for these Hutzl kits with the nice OEM-type circlips? I know it may be over-kill but it sure beats having a saw come apart or having a bring back because of the possibility of circlip failure? Is there another option for another sourced circlip with the same diameter fit and wire gauge?
I'm not sure I like popping the ear off if it leaves quite a bit less engagement in the circlip install pocket. (That may be however, the only option if you decide to make it work with what you have). What about the possibility of buying a Meteor piston for these Hutzl kits with the nice OEM-type circlips? I know it may be over-kill but it sure beats having a saw come apart or having a bring back because of the possibility of circlip failure? Is there another option for another sourced circlip with the same diameter fit and wire gauge?
fearofpavement
Trying them all
Between cylinder kits and bare pistons already in stock I probably have about 10 sets of piston clips so I will cut the clips before installing them. The Huztl pistons are fine, never had any quality issues with those that I recall. Of all the saws I built with the Huztl kits, this is the only one that's had a failure of any sort (that I'm aware of). I'm really hoping this was a one off and not an inevitable event for every clip... I've decided that I'm not going to disassemble the saws I've already completed but will mod all future ones.
I too have had a couple of those softer metal aftermarket single tang p.o.s. clips break in the past. They usually caused cylinder damage, which Is aggravating as hell! Some in my opinion have a tang that Is too long. Logic dictates that it would have more mass, and thus more inertial force.
At 12,000 rpm It Is probably flexing, causing metal fatigue; especially If the tang Is not lined up parallel to the bore. I am always careful removing the original oem circlips so I can reuse them. As you mentioned; some AM pistons have a deeper groove, but I've only ever seen one oem clip that let the pin slide past the clip, which left a death scratch a cylinder wall. So, because of that happening, I always include the step of applying a pushing force with closed needle nose pliers to the opposite side to confirm it can't slide past the clip. Although the Stihl manuals suggest you don't reuse wrist pin clips, I've never had any resulting problems reusing any. I have literally reused thousands of them. I don't know many techs who would buy new clips when they had to replace a crankcase half. I make sure they are not bent or twisted, then gently stretch them back out to their original shape so that there will be sufficient outward force that they don't easily move after they are installed in the clips' groove in the piston.
At 12,000 rpm It Is probably flexing, causing metal fatigue; especially If the tang Is not lined up parallel to the bore. I am always careful removing the original oem circlips so I can reuse them. As you mentioned; some AM pistons have a deeper groove, but I've only ever seen one oem clip that let the pin slide past the clip, which left a death scratch a cylinder wall. So, because of that happening, I always include the step of applying a pushing force with closed needle nose pliers to the opposite side to confirm it can't slide past the clip. Although the Stihl manuals suggest you don't reuse wrist pin clips, I've never had any resulting problems reusing any. I have literally reused thousands of them. I don't know many techs who would buy new clips when they had to replace a crankcase half. I make sure they are not bent or twisted, then gently stretch them back out to their original shape so that there will be sufficient outward force that they don't easily move after they are installed in the clips' groove in the piston.
Stihl used 2-ear circlips into the 90s (024 AV, for example). If there is no notch to pry out the old circlip, ears are very helpful.
2 ears allow installation/removal with less stress on the circlip itself. Single-ear circlips tend to get twisted when installed and more so when removed.
I re-use circlips on my saws if they show no signs of distortion/fatigue.
2 ears allow installation/removal with less stress on the circlip itself. Single-ear circlips tend to get twisted when installed and more so when removed.
I re-use circlips on my saws if they show no signs of distortion/fatigue.
fearofpavement
Trying them all
I like the 2 eared circlips as they make installation/removal very simple. Just don't see them often. The problem with the Stihl circlips on the Farmertec pistons is that the diameters are significantly different. (thickness of the clip material)
Some echo come oem with 2 ears. I stay away from 2 ear aftermarket ones though and will not use them.
OEM echo
The ears should be installed either straight up or down. Steve
Examine the 'eared' clips closely. The die that forms the ear will leave a nick in the wire on some AM clips. Obviously a stress riser that will eventually break. Don't use 'em.
Since I PM'd two guys what I was trying I thought I'd type once here.Got Ms 361 clips called 11mm from Stihl.They are still a thinner wire than was supplied.My supplied clips and Stihl 10mm spun in groove too easily I felt.The 11mm from the MS361 fits great,have to use force to move it,just doesn't show a lot of wire sticking up.When you insert pin you cannot push it past.Even tried a hammer tap past and OK.I wondered if anyone knew which Echo might have a 10mm,11mm pin so I could try and see their clips?Dave
Thats how the saw came in and never been apart before. Still like that right now as it is a parts saw.
LegDeLimber
Addicted to ArboristSite
kuhndog, glad you mentioned the Echo clips. I was forgetting about this
piston for a PB-620 backpack blower.
The pin is 10mm.
The clip wire is .030 diam.
The area of the radius going into the ears, it thickens about .002.
The free laying clip is about .452 ~.453 circle.
and yes, my calipers need a trip to the demagnifier, again.
I'd have done it before shooting the pics, but the demag unit is currently my friends house.
piston for a PB-620 backpack blower.
The pin is 10mm.
The clip wire is .030 diam.
The area of the radius going into the ears, it thickens about .002.
The free laying clip is about .452 ~.453 circle.
and yes, my calipers need a trip to the demagnifier, again.
I'd have done it before shooting the pics, but the demag unit is currently my friends house.
