Stihl MS261 coil issues and piston scarring

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matthewmore

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Indianapolis, IN, United States
Hello,
My Stihl MS261 wouldn't crank. I couldn't get it to spark, so I took it to the local dealership. They said it was indeed the coil causing the no spark issue, but they noted that the piston has some severe scarring on the exhaust side. They suggested it wouldn't be worth putting the coil on with the engine damaged.

1. Is it worth putting a coil on and running it as is? Just want to get some second opinions before I give up on this very nice piece of equipment.

2. Is the coil difficult to acquire or replace? If it's cheap enough, maybe it's worth my while to just throw one on and see what I find?
 
We would need to see a pic of the piston to see how badly it is damaged. A scored piston will only get worse very quickly and may seize the engine up tight, sometimes there will be more damage caused also. Just putting a new coil on it and running it as is may get a few hours out of it but eventually it will cause much more damage, imagine two rough surfaces rubbing together at 9-10 thousand RPM.
 
Hello,
My Stihl MS261 wouldn't crank. I couldn't get it to spark, so I took it to the local dealership. They said it was indeed the coil causing the no spark issue, but they noted that the piston has some severe scarring on the exhaust side. They suggested it wouldn't be worth putting the coil on with the engine damaged.

1. Is it worth putting a coil on and running it as is? Just want to get some second opinions before I give up on this very nice piece of equipment.

2. Is the coil difficult to acquire or replace? If it's cheap enough, maybe it's worth my while to just throw one on and see what I find?

Get a T27 torx driver and remove the muffler. While you are at it, see if the dealer (Stealer?) had removed it when it was examined. If no evidence muffler was removed, the dealer is a Stealer.

Take pictures of the piston and post them here. Rotate the engine so picture show the top (rings) and bottom of the piston (skirt).

We will help you fix it, a 261 is worth fixing with OEM parts.
 
Question guys. If the piston is scored, wouldn't the cylinder also be damaged? On a 4 stroke, you can sometimes hone out minor scratches, but severe scoring usually means boring the cyl and fitting new rings.
 
Question guys. If the piston is scored, wouldn't the cylinder also be damaged? On a 4 stroke, you can sometimes hone out minor scratches, but severe scoring usually means boring the cyl and fitting new rings.

Saws have a hard thin plating of chrome or nickel alloy. It is really tough. They cannot be bored out for an oversize piston.

Usually you can just clean off the melted on aluminum/piston smear. Lots of info here on how to do that.

You were thinking of 4-strokes with cast iron liners
 
I have seen more than one time where a repair shop and dealers shop where they deemed a piston scored when in reality it only had a few carbon streaks that could easily be cleaned up but the shops won`t clean any pistons or cylinders and reuse them. They always told the customer that they needed a new saw. With bit of effort all of those saws was cleaned up and put back in service. The shops say they won`t do it because they cannot guarantee just a cleanup but I have also seen where after putting on a new P&C that they would not guarantee a saw returned with a scored piston. Many times the saw was never tested for air tightness after the repair.
 
May sound crazy, but there are a bunch of us that could have that saw running in a couple of hours.

And, everybody knows it. So, it may be monetarily wise to sell it on eBay as a parts saw than pay a dealer whatever. And, buy something new. People pay good money for parts saws because they figure they can get them up and running and flip them.
 
May sound crazy, but there are a bunch of us that could have that saw running in a couple of hours.

And, everybody knows it. So, it may be monetarily wise to sell it on eBay as a parts saw than pay a dealer whatever. And, buy something new. People pay good money for parts saws because they figure they can get them up and running and flip them.
That has happened to me several times. I have repaired saws for the price of the parts only and then found out later that the customer flipped the saw for profit because my repair price was so low. My barber told me that I should have charged twice as much as I did.
 
My barber told me that I should have charged twice as much as I did.
That has always been a tough call. I had my own electrical contracting business for 45 years. Some folks tell you that you charge too much and a few (after the job is over) tell you the price was too low. I had a plumber friend who said he doubled his prices, thinking he would lose half his customers but have the same income and less work. No idea if he followed through - but he was always very busy booked two weeks ahead (he was an excellent plumber). Talk is cheap.
 
Yes, many times we must give an estimate without a tear down. Yes, you must pull the muffler, carb also if a view is available.
AND many times I have tore one down to check the actual condition and been stuck with an unsaleable unit. The customer just walk away and leaves you with nothing. No compensation for diag, nothing. As for selling the parts and recouping losses, that is great if you have the time.
If you are capable of your own repairs and do not figure labor, you surely can fix many units.
BUT are you willing to guarantee the work and if it comes back, eat the repairs?

I get doing it for yourself or a friend, relative, neighbor.
But will that keep the doors open on a business?
Some people want an honest estimate.
Some just want the magic wand.
BUT the next time it comes in, the first words will be "you just worked on it". (Meaning- now it is free)

How many chances you want to take for nothing?

Remember, we that are able are still a small percentage.
Yes, I am preaching to the choir.
I am ready to duck now.
 
I got two MS261's for free from a tree service. Both had low compression . The store quoted them something for a rebuild and they decided to just buy new.

One the cylinder cleaned up nicely and I put a piston in it. Still have it.

The other had a bad decompression valve. Sold it to the guy who leases my farm for $100.
 
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