Stihl MS261 coil issues and piston scarring

[matthewmore]

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?

 

[pioneerguy600]

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.

 

[DND 9000]

If you want to have a working saw in the long run, the cause of the scoring must be found first and eliminated. After that I would go for the new ignition module. Otherwise it makes no sense and is thrown out money.

 

[oldbuzzard]

Without knowing how competent/honest the dealer is I wouldn’t take their word on scoring. My experience is many just use that as an excuse to sell you a new saw because they don’t want to mess with fixing yours. Pull the muffler and feel for yourself.

 

[Mad Professor]

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.

 

[Chainsaw Pete]

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.

 

[Mad Professor]

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

 

[pioneerguy600]

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.

 

[ZeroJunk]

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.

 

[Mad Professor]

OP must be shopping T-27 drivers........

 

[Wood Doctor]

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.

 

[Chainsaw Pete]

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.