pleasant

Well, not really...comes down to eye and experience deciding whether a cylinder is reusable. If you would rather not do the job twice and know you have a defined datum point, then my advice would be to replace both cylinder and piston as a matched pair. The pattern brands spud has mentioned are good and not overly expensive. As a dealer we would always fit as a matched pair (OEM parts only) as the customer would baulk at us charging him/her twice for doing the job if we find re-using a used cylinder with a new piston is not compatible. We need to ensure the job is right first time. If it's your time and labour it's not so much an issue. A meteor pot and piston set are good and not a fortune for peace of mind knowing both parts are new

Yup. Got a km94 power unit in from a pro user. Says it wont stay running and not revving up. Says he keeps changing the plug for new every other week. Will work for a week or so them back to square one. I took the plug out and was oiled up to boogery despit only a fortnight old. Checked the paper air filer and contaminated with oil fuel mix and crud. New filter and cleaned up the plug and away it went. Was running so rich with the clogged filter and was oiling the plug up.

Don"t need dealership names etc.....there is a reason to ask should there be any members that fit the description. Thanks.

Interesting to note, the adult (over 23 years) national minimum wage is going up in April to £10.42 per hour. Therefore the minimum the lowest of the low jobs have to pay for a 38.5 hour week (as an example) is going to be just shy of £21k PA. Puts doing a job with professional qualifications and experience into context. So if you have spent a fortune on training, got your tickets and are working in the pouring rain, or minus 5 ground clearing for £25k, for £4k less you could be in the warm with all the benefits of working for a multi national doing the most basic job in the organisation.....look at Tesco- they will be offering DAY time full time shelf stacking jobs after April for £11.50 per hour- £23k a year. Think about it. (I am, at my age!)

by 'adding' choke you are adding fuel, so manually overcompensating for a weak oil/fuel ratio. So, yes quite possibly an air leak. Same situation with machines that have been left for sometime with old mix in the system. Will start on choke- stalls as choke comes off. Indicates a 'blockage' in the carb, so enrichening artificially with the choke will overcome it

When you say 'checked the compression' what is the cold reading in psi?

Difference is spud....on the repair forums like this one, most of us know what we're talking about....and are qualified to do so. Whereas some of the other threads you mention.......😅

Get it to do exactly as you say again, but don't leave it for the 10 or 20 minutes before trying to start it again. I would suggest as soon as it plays up, undo the fuel filler cap and see if it improves without having to leave it. That's the cheapest and easiest bit of problem solving before going forward. Then let us know if it makes any difference

How long is 'a good while'? A few minutes, half an hour, an hour, a mornings work? Once it's started 'bogging down' does the cycle repeat itself, or once it's bogged down it will carry on in that state forever, or if you leave it for how long before it starts and runs fine before it repeats? When you say bogging down, does the chain stop or slow down to a crawl in the cut but engine rpm stay the same, or do rpm's increase with a stalled chain, or is it the engine rpm's that bog down thus slowing the rotation of the chain. When it does this can you take it out the cut immediately and will the engine accelerate normally straight away until you put it immediately back in the cut?

Pleasure. Good luck and thanks for getting back to us. Make sure you update us with progress...always good to know. 👍

Blimey that piston is scrap..the cylinder is bad but may be salvagable. Although i am no expert in resurrecting these things unlike others on here. As a main dealer effectively 'making good' a repair when the correct process as far as stihl are concerned would be to replace with new oem.is a no no. We had a 661 in last year...similar story to yours, although wasnt a recent purchase from the company owner that brought it in. I normally charge an upfront estaimate fee, but on this occasion it was never taken...presumably because the assumption was it had been run on a weak mix. So a piston and barrel were the obvious issue as far as my receptionist thought. In a cock up of all proportions, my more 'junior mechanic assumed the same, so he fitted new genuine piston, cylinder and base gasket at £170. Labour was around £50 all plus vat. All parts now fitted, mechanic pulled it over with fresh correct mix in the system. Fired once or twice then tried to fire a few times after than but wouldn't start and sounded pretty bad when pulled over. Further tests showed up a collapsed crank bearing on the recoil side so was leaning the mix off hence the scoring. I told guys to stop pulling it over....rung customer to explain. Not happy as bill was goinmg to be huge. Told us he wanted it back as it was when he brought it in as wasnt paying anything. So another hour or so labour later we re fitted his knackered piston and cylinder and he collected it making sure he told us we were a bunch of idiots...which on this occasion we were and i made the workshop know about how unhappy he and i was. Thinking i could salvage some loss by holding on to the fitted but never run piston and cylinder for another job somewhere down the line i asked for it back from the workshop. Upon inspection those two or three times our guys pulled it over an small part of the broken beearing had made its way into the combustion chamber an put two or three 'finger nail' indents in the crown of the piston and corresponding surface of the inside of the combustion chamber......so now I had a pot and piston I really couldn"t pass off as new, fitted but not run' on the 'bay' or fit as new to a future customers saw. Consequently i still have the piston and cylinder and out of pocket for that and at least two house labour....a very expensive lesson there. I would be more than happy to fit the piston and cylinder to my own saw, but not a customers even though the indents to the crown and cylinder top are miniscule. Anyone want to make me an offer? Sorry slightly off topic, but COULD be a similar issue, so be careful fitting new cylinders until you have checked the actual cause first.

As Chris Newport states above- does it still do it with the plug removed? If yes, then you don't need to wait for the new decompressor valve to arrive, as you have another issue somewhere else. One step at a time to eliminate and start with the cheapest and easiest, then work up. I will just add further....have you removed the bar and chain, then tried pulling it over? A couple of cuts would be enough time for the bar and chain to heat up, and if you have a chain with burred drivers where it may have flown off previous then this can jam in the bar and stall the saw. Admittedly once cooled it would rotate within the groove of the bar again so maybe not your primary issue. I cannot suggest incorrect width of drive link as the 660 takes 1.6mm which (aside from .404 or harvester) is the largest....unless you have the wrong bar with a narrow groove? But like I say, if it still does it when cold then discount that suggestion....I would still pull it over without the plug in and with bar and chain removed. Try and remove external resistance first, then delve in deeper.

I would be interested for further information on this. I have been an emak main dealer for nearly 30 years and have never come across an AMA branded efco/emak saw. If you can post link pics etc would be useful. Cheers

Nope...emak, have never produced that saw.....they used to rebadge a few of thier efco saws for john deere, some time ago, just like echo did, but definitely not that generic chinese saw in your pic. That saw is produced as a blank canvas machine in china by the chinese, to their design and to their quality and is then bought in bulk to be re badged and generally sold to the unsuspecting online

I couldn't agree with you more Dan. More than happy to give loads of free advice and on going support to my customers.....but to become a customer, you have to purchase otherwise you are just a browser (or anything else we can think of!) 👍

...and a very short service and repair life compared to petrol equivalents

If you are referring to the two butterfly valves in the carburettor, then this is because it isn't a traditional 2-stroke engine, but the Stihl 2-mix 2-stroke engine and operates slightly differently, predominantly to reduce emissions. It is generally referred to as a 'stratocharging' port, and is designed to put a layer of fresh air on top of the fuel/air mix in the cylinder to minimize emissions of unburnt fuel. Blue is straight air- no fuel. Hope this helps.

Stihl MS181 or Husqvarna equivalent. You can go down to the more basic Stihl MS170/180/171 models, but I find a little more spent on a 181 is money well spent- for example there is full H and L carb adjustment on the 181 which is fixed on the lower models...something to help in the future should it need tweaking. Punches above it's weight, well made, reliable, will put up with reasonable abuse and spares availability is good. Although I would advise against the 'comfort' version option which has the awful 'tooless' chain adjustment. Save your money and buy the base model 181.

added to comment #1 Purchase price of chipper/write down period/what net profit margin do you want to clear/value after three years? cost to draw up hire contract and relevant documentation cost when returned to clean, inspect and maintain ready for re-hire.

There are a load of issues than can cause a weak oil/fuel mix, but not generally on a new saw. The dealer should be able to check for other mitigating factors and exclude those if no fault found. The positioning of the scoring within the cylinder and piston can also indicate what caused the issue. It is certainly possible the quality of the fuel would have deteriorated over a couple of months unless you are using a fuel such as Aspen or a fuel stabiliser (HP Super & Ultra does have this, but not the RED HP). Time flies, and when someone says to me 'a couple of months' it normally turns out to be considerably longer. The dealer won't follow this up with Husqvarna, as they rely on their dealers to make an informed decision on their behalf, however there is nothing to stop you getting in touch with Husqvarna UK technical support if you are adamant and have a chat- they may offer a second opinion for you by inspecting it, but beware if they agree with the original diagnosis you may well be charged for this service...OR they may offer a gesture of goodwill to maybe meet part cost of they consider it to be a Grey area. You will run the risk of harming your relationship with your supplying dealer, if Husqvarna just to 'keep you quiet' decide to maybe send the parts FOC if you cover labour even if they agree with the dealers original diagnosis. Manufacturers do have a habit of doing this and it harms the creditbility of the dealership, and really p's them off. I've had it happen to me, and you lose face- even if you have been correct in diagnosis and have adhered to the dealer policy the manufacturer tells YOU to adhere to. Had a guy with a nearly new Husky hedge cutter. One of his blokes went blind into a hedge and hit some fairly thick steel security wire on the other side. Broke both push rods in the gearbox. Bloke brings it in, basically tells us what he's done. We inform him it's 'pilot error' not warranty. He rings boss, who rings Husky. They get fed up with him shouting at them as they just want a quiet life, so ring me to say they will send parts FOC and we are to fit them if he pays. Owner comes back in with hedge cutter smiling away smugly in my face, about how wrong we were and how he got his own way and we are to do as we are told by Husky. At that point I threw the parts in his general direction and told him to find another dealer to fit them if that's his attitude.

It's a brand new saw, and you are the only operator? Sustained low/zero compression due to piston/cylinder scoring and ring compression? Then the evidence speaks for itself I'm afraid. 2-strokes generally don't 'seize' They will still pull over but with little or no compression. The dealer has nothing to gain by stating it's been under oiled....in fact he will lose more by informing of this, as you probably won't have the repair done. Whereas, if it was deemed a genuine manufacturing fault under the warranty then they would get paid by the manufacturer to do the work anyway. Only time they won't get paid, if it's as a result of 'pilot error' and you don't want it repaired. They must be absolutely 100% certain the damage is NOT a result of a manufacturing defect in this case to inform you as such. From my experience none of my customers have EVER misfuelled a machine within it's warranty when there's been a major failure like yours...it's always been the machines fault! 😄

Like I stated earlier, the honda lump has a low rpm compared to an equivalent 2 stroke. So no good in a chainsaw enviromnent. The gearing in the brush cutter head allows for an increased rpm of the nylon line head to cut efficiently...if it were direct drive it simply wouldn't. In a chainsaw application. It would be a direct drive and therefore too slow to cut efficiently. The orientation of the honda and stihl 4 mix engines lend themselves to be used in an application that requires a different clutch layout than a chainsaw, so to develop a design for chainsaw application that would still have too low rpms, would be a waste of resources and money.

I won't hold my breath for many convictions. As with all new laws they introduce, they are only any good if enforced, and importantly and crucially IF there are any police officers to enforce them.....or can be bothered to. Mind you easy, soft targets seems to be the 'go to' places for forces to improve their crime figures, so with that in mind, I will have to contradict myself, and will no doubt see loads of convictions for this offence, while the more difficult job of catching burglars, rapists, robbers, vandals and the like will no doubt take a further back seat.

We have sold the AL-KO EKI2200 mains electric saws as a cheaper, but none the less superb alternative to the stihl MSE. Like the stihl this model has an inline motor, so well balanced and not so cumbersome as those that have the west to east set up. Oregon bar and chain as standard. Alloy main casing. Proper machine, well made and well priced. Ok not as cheap as an aldi special or the crap bosch offerings, but they don't pretend to be. Still cheaper than the stihl or other more 'specialist' names. A good saw

All fair points. One pro and con you may also wish to consider, which has cropped up a lot in conversation. Battery. Con No pre-warning of future operating issues Petrol. Pro Some pre-warning of iminent starting/running/performance issues prediminantly before machine packs up on a job completely. As a repairer, i have always been of the opinion, that dealing with warning issues- such as getting more difficult to start, irregular running, unusual noises etc etc are generally cheaper to deal with before it gets worse and a machine completely packs up. To me, that is a pro and con to seriously consider. Cordless stuff are like a light bulb...they either work or they don't. You can turn a working light bulb off..next time you go to turn it on it won't work. No pre-warning, no noise, no poorer performance- just doesn"t work next time you want it to.