pleasant

300 tanks of fuel is an awful lot for a lightweight domestic spec saw like an ms231. That's 15 years or so use for the average specified user cutting a few logs a couple of times a year for their wood burner

Don't mess around. Honda carbs are notoriously fussy with anything other than fresh, clean fuel. If fuel has been left in the carb for an extended period sure as eggs is eggs you will have carb issues. These horizontal Honda engine carbs are really easy to remove and replace...easy access and nothing difficult. A 10mm socket and long nose pliers to remove the rods (take pics first if not sure) and off. New carb (genuine Honda) around £60-£80.......you will pay near that for just a carb clean with no guarantee it cures the issue. Just get a carb on it and be sure it will work first time out the trap. Give me the engine numbers and I will tell you what part number to get.

I remember talking to my Husqvarna rep years ago when we were main dealers for that brand I said why do you provide grease holes and Stihl don't? He said 'if you don't grease the bar sprockets through the little grease hole on Husqvarna bars from day one, then never do. If you decide to from day one, then continually do it....it's either or, but never both.

It's an industry rule of thumb that the ideal bar length is roughly one third of the saws cc's So, your 50cc 550 ideal bar length would be (around) 16" certainly no more than 18"

You are correct. Always mix according to the oils recommended dilution ratio...not what old handbooks state.

Like i said....thats because a 20 year old mountfield isnt a modern mountfield

Releasing the opc lever (operator presence control) does not 'stall' the engine. It operates the same way as a petrol car, by cutting out the the ignition circuit to the spark plug. Stalling the engine is done by artificially richening the fuel by effectively putting the choke on an already warm or hot engine.....not good for any engine. 2 or 4 stroke. As and aside.....it would have to be a pretty awful b&q job, if you consider a modern mountfield a step up as they are shite nowadays

I collect classic and rare chainsaws. If you want to pm me i can give you an idea of value. But condition can be more important than rarity. I may be interested in what you have to add to my collection

That engine is fitted with a manually operated choke via the throttle lever on the upper handle. The choke should 'flick off' once the throttle lever is moved back to the max revs position via that spring to the upper left of the pic. The plastic it is attached to on one end of the spring is the choke butterfly. You should be able to observe that plastic 'lever' flicking off when you move the throttle control off the choke position. If it doesn't move, then the choke is staying on whilst in use and will run rich which will cause the plug to foul. If not sure it is flicking off when the throttle lever is moved away from the choke position, simply remove the air filter outer cover and the filter itself and observe the choke butterfly through the intake hole inside the filter casing. If the butterfly doesn't move when the choke is taken off, then that is no doubt your issue...however in 25 years on working with Briggs engines like yours, I would be surprised. Yours is an early model hayter and there should a small slotted screw to the front of the carb that will control the fuel richness. It is actually on the front of the carb underneath that pic of the governor assembly. A small long flat bladed screwdriver is what your need to adjust the fuel flow via that screw. Anti clockwise with richen it up, clockwise will lean it off. Do a quarter turn at a time. If someone before has over richened it then you will get a fouled plug, but them may have done that to overcome another issue with the carb such as a hunting issue. Below is a pic of the type of carb, and it is the brass screw you should be looking for.....it's only the early carbs that had this....yours may not have one, in which case it is a fixed jet carb and as you have changed stuff I would suggest already then I would be scratching my head without physically seeing it or hearing it running.

I would seriously hope they aren't using that. Old engine oil is just full of swarf and various other engine deposits that will very quickly fail your pump, block oil holes and burn your bar up.

Who did the work?

Requiring a 16" bar on a 'budget' battery chainsaw is pushing it a bit...particularly for the budget. That's a lot of load on a cheapie....can you get away with a 14" or even a 12" bar?

That's a genuine Echo product.

Agree. Sold loads of blower vacs over the years and you must educate operators that they are only really effective to collect leaves if it is dry and the leaves are blowing around. If they are stuck to a surface because it is damp, then they will stick to the guts of the machine and clog, thus reducing efficiency and making the collector bag (and the operator) wet, which if left in the bag will rot it, then wet dust, leaves and grit will harden like concrete in the tubes and in particular around the impellor so even if it does spin it will have a reduced suction.

Genuine Countax/Westwood switch is only £35.00, but obviously unless you are near to a supplier you will have postage on that. They are a very common failure item.