Ms201t solenoid

[Danavan]

Just picked up my ms201t from the saw dr today. 2nd time in for a solenoid replacement in 6 months (under warranty) told it is a moving part and is expected to be replaced.. This frequently? Not happy with this excuse from dealers. 

Anyone else had this issue? I was told in the shop alot do and stihl are aware.. What a joke. Fella said the part only costs £18 then the fitting and down time. Are we as end users expected to foot the bill for this shonkey workmanship? 

[Steve Bullman]

Had my Stihl since they first came out, whats that 3-4 years ago now?  never had a solenoid replaced in that time

[Stretchsaws]

The solenoid is a part that can fail but I'm not sure I'd call it a wearing part that needs regular replacement. I guess it's possible they had a bad run in the factory and the dealer is replacing bad for bad (has happened to me several times!) When I did the Stihl technical training last year they said it is a part that had caused problems with early models but should have been debugged  by now.

[billpierce]

What is the solenoid?

[Sequoia]

I have had to replace the solenoid on a year old 261.  I was told that it was a wear part.  As to what it does, it is essentially an electronic valve that sits on the back of the carb and electrically monitors the throttle.  It is the reason we can no longer adjust the carb to keep the ruddy thing running sweetly.....

[Danavan]

1 hour ago, billpierce said:

What is the solenoid? Esesially an electro magnet from my understanding. Small spring thing that wares out. (Alot in my case)

 

[harrythecat178]

In the back of my mind, I have heard of this problem before relating to supermarket fuel

[Sambo]

On ‎25‎/‎10‎/‎2017 at 23:02, harrythecat178 said:

In the back of my mind, I have heard of this problem before relating to supermarket fuel

Walbro had an article about the effects of pump fuel with a high ethanol content degrading carburettor parts over time. you could replace their rubber diaphragms with a plastic membrane to deal with the fuel.

I would guess it's the Ethanol and probably water in budget fuel that causes aggro in the carb.

[STIHL GB]

Hi,

 

I'm a little late to this thread but it's worth explaining what the fuel solenoid does and why we've seen a few failing.  Essentially it replaces the manually adjusted screws on the carburetor so the opening closing of the fuel solenoid varies the amount of fuel going into the machine. This is controlled by the m-tronic module, which is the brain of the chainsaw. 

 

What we've found in some cases is that dirt in the fuel tank has been prematurely wearing solenoids. Sometimes when the saw is hot it wont re-start and a worn solenoid is the cause, because it's not getting the amount of fuel right. 

 

We've all seen the state of kombi cans after a year or so, and we recommend that you always try to keep a clean fuel tank, keep the dirt off the top of your kombi can to prevent it going into the fuel tank, and give it a wipe down/spray at the end of the day as part of your regular saw maintenance.   You'd be surprised how much gunk can get into the fuel system, even when the cap is only off for a few seconds - and some (most) of this is usually down to a dirty can.

The solenoid can need replacing but is pretty simple to do yourselves and we'll look to get a guide created.  If a solenoid valve continues to fail, I'd also check fuel lines or the fuel filter.  Always do an M-Tronic reset on the saw after changing a carb/solenoid or M-Tronic module too. 

 

We showed a solenoid change to the guys that visited STIHL GB a few weeks back and showed how M-tronic isn' t a complicated system. It's just not that well understood  that the main parts of the saw are not that different from a non M-Tronic machine.  We've got a blog here that explains more about M-Tronic for those that want to know more:  https://blog.stihl.co.uk/stihl-m-tronic-technology-dispelling-myths/ 

 

Sambo - you're right that pump fuel can cause issues with carbs too - high ethanol fuels degrade gaskets and if left in a machine for a while can gum up. Using fuels with less ethanol like BP/Shell  or MotoMix helps. 

 

Hope this helps,  

 

Paul

Edited August 31, 2018 by STIHL GB

[spudulike]

7 hours ago, STIHL GB said:

You'd be surprised how much gunk can get into the fuel system, even when the cap is only off for a few seconds - and some (most) of this is usually down to a dirty can.

 

 

Not at all. Having drained hundreds of tanks for couriering and using a funnel with a fine gauze strainer in it, I can say the average tank is full of shyte which gets pulped and will end up in the carb one way or another.

If I find shyte in the gauze strainer, the tank gets flushed out a few times until clean - doesn't sort the owners can though.

Good luck with getting owners to clean their cans!