2 stroke failure! 80cc of pure bliss until.....

WARRIORWELDING

WARRIORWELDING

Owner opperator Of WarriorWelding LLC.
Joined
Jan 6, 2008
Location
Chillin, Hwy 64 Mocksville NC
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There is litterally fewer thing I enjoy less than running a saw. This was my favorite saw and honestly the only saw I have purchased. The rest I've used where either my father or father in-laws, uncles and so forth. Husqvarna, Sthil, Homelite,Poulan.....I've ran and used them all and some brands I've forgot.

Ran some older gas this day....done before. Ran a little under power lower octane as expected. Swapped to my new fun bar and chain. Dumped the old gas for 100 percent gas and the mix I've used off and on. (never been completely loyal to echo mix) often ran the Red bottles from Lowes. "Pro Mix". This occured somewhere between a tank to tank and a half through the new mix. I was never really burning a whole tank. Stopped for water and retensioned new chain and topped off the tank.

The saw didn't see huge action last year but I've cleaned up and cleared stuff all through fall and spring on and off. So easily a month's or two between used but not shelved for extended times.

Pre work routine was as usually. Clean filter, file, fill, fire. Saw has never needed anything else.

So the failure.... What caused it?

Bunch of guys on here have alot better knowledge than I have on diagnosing combustion engine failure. A buddy and long time 2 stroke fan and racer feels like it was purely lack of lubrication. Industrial saw less than industrial quality oil. He also wants me to rule out crank case leaking.

Any of you guys seen this first hand?

Definately will check the case before a new top end. No sense killing a expensive replacement for bad seals. I just wanna prevent the buzz kill from happening again.
 
It's a 2 stroke, you use it enough then you get to learn how to put a new top end on it. That being said, pull the jug off and see if a ring took a shit.
I think the standard answer is going to be you ran the wrong mix or straight gas.
 
braxton357 said:
It's a 2 stroke, you use it enough then you get to learn how to put a new top end on it. That being said, pull the jug off and see if a ring took a shit.
I think the standard answer is going to be you ran the wrong mix or straight gas.
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No broke rings. Definitely not straight gas. It broke free right after removing the starter pull assembly. Rings was full gummed stuck in the piston grooves and scored as well. Jug is scored as well. I have replaced a saw piston and rings before because of severe lack of compression. That saw was worked for years and was tired. It had typical signs of blow by and carbon down its length.
This one is spotless.....all but the pesky brail on the exhaust port. It matches the port size width dead on. That I find odd as well! Muffler clear and clean inside too.
 
Leaning out will cause that. So will insufficiently mixed oil in the fuel.. klotz super techniplate or r50 will prevent that as it stays in suspension (and runs to heat, not away) typical failure.
 
Im no expert, but Im going to go with it got lean and got hot, or not enough oil.
 
Also, Id rock that bike!
 
You could get a Chinesesee top end for cheap, spend some time cleaning the ports up so rings don't snag (cast flash is bad on China units) and get out cheap fixing it. Replace crank seals for cheap insurance as well as intake boot.
 
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Maybe I missed it, but what saw was it? Regardless, looks like insufficient oiling caused friction, which caused the piston to overheat and expand, resulting in a, uh, "dynamic" press fit between the bore and the piston. Especially if it broke free once it cooled off. I had a 2 stroke 4wheeler do that once when the oiler quit working (because the mix oil tank was empty ;) ).
 
jeepinmatt said:
Maybe I missed it, but what saw was it? Regardless, looks like insufficient oiling caused friction, which caused the piston to overheat and expand, resulting in a, uh, "dynamic" press fit between the bore and the piston. Especially if it broke free once it cooled off. I had a 2 stroke 4wheeler do that once when the oiler quit working (because the mix oil tank was empty ;) ).
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Echo CS-8000
 
StretchASU said:
My bet is crank seal took a shit and it leaned out.
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It's actually what I hope to find. I am 100 percent certain all ratios and oil was right. Top brand name stuff? No. Lowe's sell the crap out of it? Yes. Crank seal taking huge dump and less than top notch oil and running it full tilt in big wood........fubar!
 
Im with stretch, if your oil mix was good then its definitely an air leak. Crank seal, maybe even intake boot or impulse lines.
 
Since I am a tool flunky a vacuum pressure kit it getting ordered today to check the case and related integrity.

I really thought about just popping new stuff in it. But I want to diagnose it.

Unless somebody close has a tool I could borrow.
 
a_kelley said:
You can use that kit to pressurize the system also.. add soapy water. And low pressure.
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"tool flunky a vacuum/pressure kit it getting"
Should have read like this.
Going to stay around 8 psi for testing. Im actually kinda looking forward to messing with it. Probably buy some adapters for presurizing auto coolant too.
Yep im a tool nerd!
 
WARRIORWELDING said:
It's actually what I hope to find. I am 100 percent certain all ratios and oil was right. Top brand name stuff? No. Lowe's sell the crap out of it? Yes. Crank seal taking huge dump and less than top notch oil and running it full tilt in big wood........fubar!
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That stuff from Lowes is fine. Is it Klotz or Amsoil? No but as long as the mix and fuel quality is good, fuckin run it. I tinker on 2 stroke stuff all the time and finally had one of my free "Im sure its blown up so you can have it" saws take a shit. Amsoil Dominator is what was in it. Crank seal was the culprit. Threw that old ass poulan in the trash and grabbed the other one :lol:
 
StretchASU said:
That stuff from Lowes is fine. Is it Klotz or Amsoil? No but as long as the mix and fuel quality is good, fuckin run it. I tinker on 2 stroke stuff all the time and finally had one of my free "Im sure its blown up so you can have it" saws take a shit. Amsoil Dominator is what was in it. Crank seal was the culprit. Threw that old ass poulan in the trash and grabbed the other one :lol:
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Screenshot_2018-07-30-11-42-18.png This stuff.
 
It (might ) clean up , echo has got real thick plating . I've vac and press test stuff here in Asheboro. .. it kinda looks like a slow lean seize , bad fuel ,cheap oil , dull chain , high ambient Temps ,dirty filter...bad recipe , also could be a torn intake boot etc ...but I've never been in a 8000 echo so unfamiliar with intake setup

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termitebuffet said:
It (might ) clean up , echo has got real thick plating . I've vac and press test stuff here in Asheboro. .. it kinda looks like a slow lean seize , bad fuel ,cheap oil , dull chain , high ambient Temps ,dirty filter...bad recipe , also could be a torn intake boot etc ...but I've never been in a 8000 echo so unfamiliar with intake setup

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Out of them phrases.....one tank bad fuel, cheap oil, and high temps fit......or at least I was hot. Several other Stihl saws where pressent and working. Mine just decided everybody should take a break!
 
WARRIORWELDING said:
Out of them phrases.....one tank bad fuel, cheap oil, and high temps fit......or at least I was hot. Several other Stihl saws where pressent and working. Mine just decided everybody should take a break!
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Most all echo saws have a bypass , circuit in the carb , preventing tuning too lean ....fuel filter look good on your saw ?

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