pleasant

Well, there isnt a lot left with the electrics.....i know you said youve changed the plug, but years ago a similar issue arose with me. Spent ages testing all the electrics...to the plug out held it up against the body of the machine...great spark couldn't find anything else awry, so went back to the plug....this time no spark..changed plug and away it went. When i inspected the original plug if i held it up...great spark, but if i held it with the electrode facing downwards the internal insulator had broken away from the central core, slid down the copper core shaft and made contact with the electrode and cut the spark. Never come across it before and never since, but its always something i now check.

So. it's had two new plugs (the original and the new replacement) It's had two new flywheels (the original and your mates replacement) Its had two new modules (the original and the new replacement) You have tested the switch wiring Did the ht lead come with a new coil or did you have to unscrew and reuse the original? Have you tried it without the ground lead on the module connected? Is the ignition switch when in the on position clearing the brass earthing strip positively- not all lose so when you pull the machine over it can wobble and earth it out?

I wouldnt blame the farmers....tends to be the 'tractor drivers' they tend to employ

Scored piston I read into that.

Maybe, if you had started your OP by saying 'I've scored by piston on my relatively new MS291, and to my surprise when I got it apart it had the smaller diameter piston for an MS271, do you think the dealer would have done this as it was already on the shelf assembled, or would it have come from the factory like it? Wording it like that, does away of any inference of warranty and the invalidation thereof. It also really makes the point of whether a dealer had swapped cylinders or not irrelevant now, as you would be having to pay for a 'correct' MS291 pot and piston anyway due to your error. Just a thought, eh?

Would be rather nice for all of us out of pure curiosity if you answered the actual question I posed in the first paragraph, now we have established that you are a brilliant mechanic/farmer/debater

What was the running issue that it had, that you thought removing the cylinder/piston to inspect it....would give you the answer? I cannot think of a running issue the average consumer would have that necessitates such a major job, and even those that know what they are doing, baulk at taking out pistons on the cheaper stihl clamshell engines as its an awful, time consuming job. You either know what you are doing and know by removing the piston etc will cure/establish the problem, or if you dont know what youre doing, then attempting that job is foolhardy and all rational people I know whether they know what they are doing mechanically or not, wont do anything to that extent on a machine knowing it is still within the warranty period. If you are saying warranty isnt the issue, then you must have known the issue wasnt covered under warranty and you have attempted to repair it yourself knowing the problem was 'pilot error' and then in doing so you discovered the 'erroneous' piston...allegedly.

I appreciate that. It was in answer to someone else who mentioned warranty....wasnt you

Agree...it's a bit sniffy

Any warranty would be null and void anyway if the end user has tampered with it to that extent

I'm more of a glass half full kind of guy.

The pump is primed so the hose is full before it is tested and sealed as being accurate. From then on it dispenses the right amount of fuel to the car through the hose and nozzle. Once the trigger is released it stops the delivery at the nozzle (but not the pump, you still hear it running), so no one previous has paid for the fuel in the hose and nozzle (nor have you) Its just a primed part of the delivery system. What passes through the meter just triggers the display on the pump, the right amount comes from the hose. The feed hose could be twenty miles long, but guess what, if you put an additional gallon of fuel into the pipe, only a gallon comes out, not twenty miles worth! Any left in the pipe is not yours, or the previous customers, it belongs to the system! you only pay (and get) for what comes out, apart from a few drips!

If you can find another, buy it and make one good one out the two and use the remainder for spares for the future

Worth a call and have a friendly...but forceful chat. Dont go in with all guns blazing as that will just put the shutters up. The issue you do have though is burden of proof. If the dealership have been devious and dont want to admit it to you, then they will simply say it was factory when it was purchased and you have played with it since its left them. No proof either way is there? Furthermore....the price differential between the 271 and 291 piston and cylinder kits if purchased by a main dealer direct from stihl is negligible compared to the chance they may get 'found out' somewhere down the line, which wouldn't make sense. If you know someone that works for another stihl dealership, then a suggestion might be you ask them to check your serial number against the stihl secure registration portal...this will tell you whether it has been sold before, registered to the original purchaser, then re-registered to you when you purchased it. stihl won't tell you this information directly due to data protection, but someone with access to the dealer portal can

Be careful chopping and changing your fuelling between pump fuel and aspen...a lot dont realise a machines carb bits get 'used' to running on either/or and a machine that has been run on aspen then pump fuel can have carb diaphragm issues and vice versa. If youve always run a machine on one type of fuel then you would be wise for it to stay that way.....unless you want to change your diaphragms everytime you change to different fuels

Stick them on the bay. Early 80s mccullochs are doing ok....certainly better than sticking it in a hole in the ground....or the oppo at the tip will stick it on the bay for himself anyway

Reminds me of a customer who purchased a pole pruner online and brought it in to us apparently for a fault under warranty. Said he had assembled it correctly but stihl must have put the drive gears in the wrong way round, so the chain was going backwards. As soon as he walked through the door with it and we saw the oil filler cap was located facing the ground we knew what he had done. Its amazing how many people dont expect to pay us for sorting 'pilot errors' out like that. Not even and offer.......to make my point i used to start making an invoice out if the bloke was particularly officious. They would often say 'whats that for? I would point out the time, experience and skill over the years we have trained to know you have put the head on upside down, so heres the bill. I dont ask my solicitor questions and dont expect a bill. , but when its us.....

If anyone needs a genuine stihl ms461 piston and cylinder then i have a set available. They have been 'dry fitted' to a customers saw who refused to pay his bill, so we took all the new stuff off it and put it back to how it was when he brought it in. Had to swallow all the labour so wasnt going to swallow the parts as well! It is 'as new' just been fitted but not run. Will need one piston ring and gudgeon pin clip as they flew across the workshop floor when we removed it. They cost a fortune from stihl..happy to discuss to get some of my money back at least

Yup...461 for me as well.

My customers tend to be very 'proud' of saying things like that. And they tend to be the ones that come in all of a panic as they have an urgent job on and the machines let them down. Preventative maintenance if the cheapest maintenance of all IMO.......anything else is just waiting for your machine to fail- one day when you need it.

Oxidisation of the copper core element of the plug. Here: Erosion, Corrosion and Oxidation The material of the electrodes has oxidized, and when the oxidation is heavy, it will be green on the surface. The surface of the electrodes is also fretted and rough. How do I "read" a spark plug? - NGK Spark Plugs NGKSPARKPLUGS.COM Learn how to analyze your engine's overall operating condition just by looking at your spark plugs. Find this and other DIY...

Karcher are shite. They are the black and decker of the pressure washer world. Unless you go for a 'proper karcher which is made for pro use and you are into the high 100's and thousands. Been selling shoddy stuff in the sheds for years off the back of their name in the pro sector

Clutch drum bearing disintegrating or collapsing? Or worse case scenario crank bearings failing or crank bent. Remove bar and cover and see if your clutch drum is running elliptically . Watch the gap between the drum and the body of the saw

' look and watch son, i will show you how its done'

Blimey...that sort of money up there will buy a house and retirement surely? 🤪