Cheap piston = BOOOOOM! (pics)

[jockeydeuce]

I know better and I've read all the warnings......

I bought a large lot of ex dealer stock a couple weeks ago, and there was a whole box of new pistons, cylinder kits, etc. in the lot...All of it is the cheap aftermarket stuff, but I decided I might as well use it to bring some carcasses back to life. I just built a 365 Husky and used one of the pistons.....The saw fired right up with good compression and I was tuning it, when all of a sudden, BANG!!!



I would have sworn the ring locating pin was where it should have been, but now I'm not sure....It's pushed into the groove so deep, it was doing nothing.





I got lucky and there is virtually no damage to the port where the ring caught......I'll be touchign up the chamfer in the port and putting a Meteor in tomorrow.

 

[fearofpavement]

Just hate it when stuff like that happens. Did you recover all the pieces? (don't want a repeat)

 

[Big_Wood]

any idea on the brand. i've heard horror stories about the golf 365 pistons. i used one just before christmas and that saw has cut one heck of alot of wood since then. got lucky i guess.

 

[jockeydeuce]

Just hate it when stuff like that happens. Did you recover all the pieces? (don't want a repeat)

Definitely will and definitely dont!

any idea on the brand. i've heard horror stories about the golf 365 pistons. i used one just before christmas and that saw has cut one heck of alot of wood since then. got lucky i guess.

I don't believe they're a Golf. They are the ones that come in a plain white box....Same ones that Barry in Mill Bay sells.

 

[Big_Wood]

i believe those plain white box ones are from baileys. every piston i've ordered from barry was a hyway in a marked box but he very well could be reselling baileys kits as well. wouldn't surprise me.

 

[jockeydeuce]

I've got a few pistons from him for saws that Meteor and Episan don't make pistons for, and they have always been the plain white boxes.....Never got a Hyway from him so far.

I'm a little freaked out because I just built a really nice 372XPG with one of these pistons on the weekend......I think I'm going to pop the top back off and have a look at the locating pin.....I looked at all the others I got in this group of stuff and they all look fine, so I probably just got the Monday piston, but I can't take a chance.

 

[HTTR]

Ouch! Never seen a piston fail that badly. I'm very interested in what brand it is, so that I can avoid it.

 

[motorman1]

Wow! You got really lucky. No cylinder damage at all? Knock on wood, I haven't had any AM piston failures yet, and I've used quite a few Golfs and Makos.

 

[dozerdan]

I tried a Golf piston in a 346 years ago when I first saw them on the market. At that time nothing was ever mentioned of them on here. It lasted about 5 seconds and it looked just like the one that you have.

Later
Dan

 

[dozerdan]

I've got a few pistons from him for saws that Meteor and Episan don't make pistons for, and they have always been the plain white boxes.....Never got a Hyway from him so far.

I'm a little freaked out because I just built a really nice 372XPG with one of these pistons on the weekend......I think I'm going to pop the top back off and have a look at the locating pin.....I looked at all the others I got in this group of stuff and they all look fine, so I probably just got the Monday piston, but I can't take a chance.

Do yourself a favor and replace that piston with a good Meteor. 50.00 plus shipping is cheap insurance for a nice 372.

Later
Dan

 

[Poleman]

Same here...Had a Golf explode in a Stihl 044. Runed the cylinder also..took a chunk of intake port out but no other damage. Flushed bottom end out and put a Hyway kit in from weedeaterman and been going strong for about two years now!!

Hard lesson learned on using the Golf brand. I now only will use Meteor or Hyway now. I get my kits from weedeaterman (usually Hyway) because I likle the way they look and I have had NO issues with them at all.

 

[watsonr]

Turn the piston over and on the inside of the skirt, if it's a Golf, it will have it in block letters. May be hard to read, take a pic with phone and try to read it then.

 

[pioneerguy600]

Locating pins have been a problem with some AM pistons for many years now, some pins will push in and others work their way out. Either way damage is done, its best to tap the ring end pins with a punch and hammer just to sound out if the pin is tight or not before install. The piston swells faster than the steel pin so the fit of the pin to the piston needs to be very tight.

 

[watsonr]

Make sure the pin doesn't go all the way thru either. Some pin holes are drilled clear thru and you may never know until you tap it. The port shape also effects ring compression as the ring is squeezed into the lan just as it goes past the apex of the roof of the port.

 

[Modifiedmark]

Don't feel too bad Rob, at least the cyl was ok. I have been there as well and the cyl didn't take it too well in my case's

 

[jockeydeuce]

Don't feel too bad Rob, at least the cyl was ok. I have been there as well and the cyl didn't take it too well in my case's

It could have been much worse......Out of hundreds of builds, this is my first failure and everyone likes pics of failures...lol

I just had to grind a little more chamfer on the Ex port, as the ring catch pushed a little metal where it caught. I normally use Meteors pretty much exclusively and keep about 50 new pistons on the shelf for my common builds......I'm sure these other pistons aren't Golfs.

 

[Modifiedmark]

I think its the cheap rings that are the trouble a lot of times, more then the piston itself..

 

[jockeydeuce]

I think its the cheap rings that are the trouble a lot of times, more then the piston itself..

Could be, but not in this case.....The pushed in locating pin, let the ring gap float all the way around to the Ex side before it caught.

Just slid the cylinder back over a new Meteor.....Plan "B".

 

[watsonr]

I think its the cheap rings that are the trouble a lot of times, more then the piston itself..

I agree and the more I hear from guys about these kinds of things... a good set can make up for lower compression caused by excessive squish, poorly beveled intake/exhaust openings and even the shape itself.

 

[old 040]

got my fingers crossed on a golf i just installed in a 242, the only reason for using the golf was that the cylinder cleaned up "ok", but wanted to see without spending more than needed what the compression would be like. assembled it yesterday and ran it for about ten minutes, let it cool, checked compression, was at 125 psi, took it apart again today and all looked real good, reset the squish to .018 (it was .030) and compression jumped to 165 psi, running great now, but i'm still going to order a meteor for it before any real use gets put to it.................