Ebay cylinder piston kits, 028 Super?

[Bret4207]

I've got an 028, 3 actually, on the bench now. Rather than go with a good used standard piston/cyl, I though about upgrading to a Super piston/cyl. I see kits on Ebay for not a lot of $. No brand name. Anyone tried these or am I better off with a brand name set? Example I;m speaking of- https://www.ebay.com/itm/46mm-Cylin...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l9372

 

[cranman1951]

I've used a few of the cheap China kits on 026's and 028's and am going to do one this week on a 251. They look good coming out of the box, they go together nicely, they start and run when I'm done. I can't vouch for their longevity , but for $30 to get a toasted saw running, what the heck....

 

[RED-85-Z51]

Its a dice roll...

Sent from my LM-G820 using Tapatalk

 

[Woodslasher]

I can't speak for all of the cheaper kits, but a 3120 I just tore down had a cheap Chinese top end on it that was trash. The squishband was so huge my Proline piston stop was too short to even graze the piston and my long, oem Husky piston stop only stopped it ~1/8 of an inch from TDC. Also, when I went to pull the clutch but the previously untouched piston crown buckled to the point that the stop no longer "stopped" the piston. An air impact just blew the clutch off anyways but those issues, along with the circlips utter lack of strength, has made me distrustful of cheap top end kits. For scale, the piston in the pic is 60mm across and look at how wide the dent is in relation to the overall diameter. No oem piston I've ever seen, no matter how abused, has had a dent remotely close to the pictured one after many uses of a metal piston stop, and the pictured one got that dent from just one use of a metal piston stop.

 

[cranman1951]

Well I just learned to never use a metal piston stop. I've never checked squish on my import cylinders, but I would expect them to be sloppy. I'm expecting to put a ms 251 together tomorow and was going to check it....I just did my first squish test a few days ago and will be doing it on all of my builds from now on!

 

[bwalker]

I can't speak for all of the cheaper kits, but a 3120 I just tore down had a cheap Chinese top end on it that was trash. The squishband was so huge my Proline piston stop was too short to even graze the piston and my long, oem Husky piston stop only stopped it ~1/8 of an inch from TDC. Also, when I went to pull the clutch but the previously untouched piston crown buckled to the point that the stop no longer "stopped" the piston. An air impact just blew the clutch off anyways but those issues, along with the circlips utter lack of strength, has made me distrustful of cheap top end kits. For scale, the piston in the pic is 60mm across and look at how wide the dent is in relation to the overall diameter. No oem piston I've ever seen, no matter how abused, has had a dent remotely close to the pictured one after many uses of a metal piston stop, and the pictured one got that dent from just one use of a metal piston stop.
View attachment 883921

That's why I have always preferred using starter rope for a stop vs something rigid.

 

[Woodslasher]

I can't speak for all of the cheaper kits, but a 3120 I just tore down had a cheap Chinese top end on it that was trash. The squishband was so huge my Proline piston stop was too short to even graze the piston and my long, oem Husky piston stop only stopped it ~1/8 of an inch from TDC. Also, when I went to pull the clutch but the previously untouched piston crown buckled to the point that the stop no longer "stopped" the piston. An air impact just blew the clutch off anyways but those issues, along with the circlips utter lack of strength, has made me distrustful of cheap top end kits. For scale, the piston in the pic is 60mm across and look at how wide the dent is in relation to the overall diameter. No oem piston I've ever seen, no matter how abused, has had a dent remotely close to the pictured one after many uses of a metal piston stop, and the pictured one got that dent from just one use of a metal piston stop.

Well I just learned to never use a metal piston stop. I've never checked squish on my import cylinders, but I would expect them to be sloppy. I'm expecting to put a ms 251 together tomorrow and was going to check it....I just did my first squish test a few days ago and will be doing it on all of my builds from now on!

If you'll notice, in my original post I said I've never seen an oem piston suffer from this problem, just that particular aftermarket pot metal piston. I had a dozen+ oem pistons that were scored/worn out with minor marks on the crown from metal stops sitting in my shop, but I chucked 'em in a cleaning spree a week or so ago. They had a small ding in the top from the stop contacting them but were still solid while the chinese one just buckled.

 

[cranman1951]

I just use a starter rope...and I'm sure the OEM is sturdier then the Chinese.....but the Chinese is sturdy enough to fire and cut wood