Stihl MS180 Oh boy!

[BetzyF4ever]

Hey folks, Betzy from Ontario Canuck land here. I just picked up a dual buy with this MS180 as the the second saw, he said it stalled while stuck in a tree and never ran after. Well maybe, I’m not not a mechanic so I’m no expert but it’s seems maybe they had some non mixed gas used here??
The video shows the piston through the muffler port…
Any of you fine gals or gents done a rebuild on one of these before? Tips would be appreciated
View attachment IMG_5364.mov

 

[SteveSr]

When your piston looks like a bar code it is time for a new piston and cylinder!

 

[Marley5]

It happens.
My long time buddy who's been around chainsaws for over 50 years recently bought a new MS 250 and straight gassed it on very 1st tank, seized...... warranty denied.

 

[singinwoodwackr]

Not worth OE replacement parts, imo. Used 170/180 series are $100 saws in good running condition. The cyl may be ok but that piston/is toast.
I’ve done several. AM piston kits are $12.

 

[BetzyF4ever]

When your piston looks like a bar code it is time for a new piston and cylinder!

Figured as much Is this usually from using unmixed gas or what else could cause this??

 

[BetzyF4ever]

It happens.
My long time buddy who's been around chainsaws for over 50 years recently bought a new MS 250 and straight gassed it on very 1st tank, seized...... warranty denied.

Thats not fun! He wont soon forget that lesson...

 

[BetzyF4ever]

Not worth OE replacement parts, imo. Used 170/180 series are $100 saws in good running condition. The cyl may be ok but that piston/is toast.
I’ve done several. AM piston kits are $12.

Thanks much for the guidance, AM you say?? Oh After Market

 

[J D]

Figured as much Is this usually from using unmixed gas or what else could cause this??

Running lean will do it.
Check the fuel in the tank for oil & when you get it apart check inside the crank case & under the piston for any residual oil. If its dry then that was likely the issue.
https://www.madsens1.com/how-to-read-a-damaged-piston
If possible vac/pressure test the saw before disassembly. A vac/pressure test is a must after repairing this kind of failure!
These saws are known to run lean (the newer ones are the worst) & the carbs are non adjustable without replacing or drilling out the main jet. Fitting a ms210 carb is a common upgrade but it requires drilling holes in the cover. I prefer to modify the jet

 

[Marley5]

Running lean will do it.

Yes.
The last 3 new saws that I bought, 2 Echo's and 1 Stihl all ran lean from factory.
This makes me wonder if they're trying to compensate for the restricted muffler's and/or the average homeowner won't run them enough to burn them up. Idk

 

[BetzyF4ever]

Yes.
The last 3 new saws that I bought, 2 Echo's and 1 Stihl all ran lean from factory.
This makes me wonder if they're trying to compensate for the restricted muffler's and/or the average homeowner won't run them enough to burn them up. Idk

Well now aint that a great question for the engineers at Echo and Stihl!! I'll ask them next time we have coffee together lol

 

[GMB74]

As stated above, fixing MS170/180's is on a par with doing major work on a weed wacker. Not worth it when you can buy a brand new one with a warranty (as long as you remember to mix oil with the gas!) for a couple hundred bucks.
It's just not cost effective.
If you want to repair it yourself for the education and entertainment value, that makes more sense.
Write off your expenses to the cost of tuition.
Plenty of guys on here to help you along the way.
Start with a pressure/vacuum test to be sure of what you are dealing with.