spudulike

Most building materials are mad expensive at the moment. Probably a perfect storm of inflation and shortages.

I didn't like to suggest a Heath Robinson repair on a primary safety device but the dowel does go through to the muffler side so a threaded rod...yada yada yada may work but you don't want the bugger to fail with the bar heading for your head at 60mph If you tackle the case replacement, you can say you are a man when the thing is running and working fine. 8 months ago, I would have sent you a crankcase for the postage but they are long gone.

That's bad, the only safe thing to do is to replace half the crankcase which is a relatively big job. The only positive is that you can probably pick up a cheap secondhand part.

One turn out on the H and L screw is the standard setting. I generally find that I need to pull the limiters on older 460s as they loosen up and start over revving but, in your case....a carb strip, clean and reassemble makes sense, most saws benefit from it. The air filter - clean it with oil based fluid and a compressor, worth replacing the fuel filter then put it all back together again and tach it. You could just run it though....choice is yours.....looks like the H setting was a bit of a red herring!

I don't believe so. I first came across him on Arborist Site, I don't think he was after world domination but a bloke down the pub, Mr Blofield,,,that is a different story. Do we discuss fish now?

That piston looks pretty good to me. The bottom is a bit polished but that does happen, the middle pic shows some original machining marks on the right hand side of the port so it again looks OK and the rings are free in their piston grooves. I would say it looks like something else is going down here. Mark Skylands suggestion is a good one as I have also found that the MS460 does tend to draw in fine sawdust and dump it behind the metering diaphragm so worth doing as he suggested. As far as replacing the carb....don't, just clean it out, check the diaphragms, possibly change them and then retune. From what I have seen, I would say the piston is probably OK so lets get the carb out, check it out and see if there are any issues. It is weird that the carb H screw is turned fully in....I am taking it that the limit cap is off? The only time I have seen this is when a saw has excessive bore wear so do the carb work and if that doesn't help, check the cylinder. Is your air filter 100% clean as a dirty one will significantly richen the mixture? You could try taking the air filter off, start the machine and see if you grab the throttle that you get a puff of fuel vapour out of the back of the carb. If you do, it is a sign of wear on the piston, bore or both around the inlet side causing a bit of free-porting which isn't good.

I thought Mastermind was a fella called Randy in the US who likes to strip and port chainsaws!

If you order a compression gauge, buy the Gunson HiGauge as it works, some are specifically OK for cars but small engines produce a much small volume of air so don't register the actual engine compression. Checking the bore - the visual check on the exhaust side as discussed earlier is fine. Just move the piston down to near the bottom of its stroke and visually check the bore through the spark plug hole. You can shine a small LED torch down the hole to help. No need to pull the saw over and risk burning the hairs off your arm like I did once! You can then raise the piston to cover the exhaust port and inspect the piston ring and skirt. It shouldn't have any deep vertical black lines on it. To SEE if the bore plating is worn through (only seen this a few times so is rare), you will need to remove the cylinder and inspect the bore on the inlet side. If the plating has worn through, it will be a lighter in colour as you will be seeing patches of aluminium rather than the Nikasil plating. You have a few methods to check a piston....Calipers to measure the diameter and compare to a new piston. You can measure the depth of the piston rings inner to outer surfaces front and both ends and compare to a new part. You can push the piston ring in to the bore so it sits square and measure the end gap...7 thou is good, anything over 20 thou is getting bad....sorry about using imperial!! A simple check is to take the piston, put it in the base of the cylinder and try to rock it forward and back. If you have done a few, you will be able to feel any excessive wear. The other technique is to put a ringless piston in the bore, cover the spark plug hole and then pump it up and down the bore. A badly worn piston won't create much of a feeling of compression when pushing the piston in to the cylinder. You can purchase aftermarket cylinder and piston kits - typically £70-95 for anything decent and the OEM part £195. When I said "roughen the bore" - this can be done with wet and dry paper or a small cylinder hone but if you do this, don't get the hone snagged in the lower transfers or exhaust port. Ball hones are available but are pricey. Long and short...check the piston and bore visually by removing the plug and muffler. Get a pic up on here of the piston front. If you can see the original machining lines, the piston is probably fine...pics replace a thousand words!! If the saw has seen many hundreds of hours use, it is probably the piston so take the cylinder off...more pics for second opinion and fit a new piston if the bore is good. If you do change the piston, fit it the correct way round and take A LOT OF CARE fitting the circlips....open ends towards the crankcase!

Your question "is this OK".....No, it isn't. Having had a few machines in and played around a bit, from experience, when a machine needs the H screw wound in further than it should to make high revs, it generally means that your piston is well past it, the saw is low on compression and the only way to get the engine to hit high revs is to lean the saw right down. The good news is that hopefully, the issue is with a worn piston and not the bore but you will need to strip the top end down, inspect the bore and plating and then the piston. You should be able to fit a Meteor or Hyway piston, roughen up the bore and fit, retune and it should be back to A1. If the bore plating is worn then it is more likely on the inlet side through fine sawdust getting past the air filter and that means a new top end. It is possible the piston has nipped up but again, a new piston and a bit of cylinder work should bring it back. The 460 is a pretty strong saw and have seen 046s in 20 years old and still very usable. The compression on these saws is generally 160-170 psi which is pretty high on a large saw. I would suspect that yours will be around 140 so test if you can.

Nah, 5 mins in the old air fryer...works wonders. BTW....DON'T TRY THIS AT HOME....it should read "TRY"!!!

I would fry new fuel filters and use a bit of carb/brake cleaner and air line on the air filters first. Most don't clean or understand how important a clean air filter is. The saws will loosen up a bit with use - 2 months use isn't really enough.

Here is my view....I use an online supplier for 98% of my machine parts ......sorry Mark, been with them for years and never had a bad experience but have purchased Echo/Some Husqvarna parts from your outfit and never had issues. My main supplier.....If the part is out of stock, I order anyway as they offer good prices, reasonable carriage, I know they will chase the part through until it is delivered (phone calls if they are having issues) and I know they purchase parts direct from the manufacturer so if they can't get the part in, no one else will. Typically when they first supplied Husqvarna parts, most were out of stock but after purchasing a few parts, I could depend on the parts being around 2-3 days more than their typical 1-2 days delivery if not in stock....not at all unreasonable. The long and short, if you have confidence in your supplier, you have confidence to purchase out of stock items and that they will be delivered in a reasonable time. I guess if you can get the part from others at the same price or thereabouts, I may go to others but I like to do a single large order with all I need on it and that way it is job done. The last bit is the ease of order - purchasing by Manufacturer > Machine Type > Model number and straight off an exploded parts diagram makes life nice and easy. I would say most parts...... 75-85% that I have generally ordered have been in stock rather than all of them being out of stock and the out of stock are the rest.

I think Mark is seeing dark staining on the base gasket on the first of your pics. I reckon this is from the saw being flooded from trying to start it with the choke on but needs to be clarified. The usual place 560s leak was around the front transfers but was resolved in one of the upgrades by the factory. Yours looks fine in this area. I wouldn't expect a near new machine to have any leaks from the base gasket. The old fuel mix is much more likely.

So....your description, is this from cold or hot? I ask this as from what I think you are saying, when using the "Half choke" which is the "Fast idle" setting that gives partial choke and kicks the throttle open a little, the saw revs at a higher rate than it should. So...the faster than normal revving could be the "Fast idle" mechanism not working right, an air leak or the carb offering an overly lean mix at idle. The stalling on idle could also be contributed to the above. When the saw is idling, does it idle faster than it normally does? Has anyone cocked around with the carb settings to try to make it work better? Were the exact same faults present before you worked on the saw? Just making sure you haven't put something back together incorrectly!

Mmmm, it is better on the chainsaw threads than some of the other ones. At least we are relatively civil on these threads whilst others argue the toss about Covid and Politics!

I got mine in pots with compost, a good dousing straight away and in to the greenhouse. Will stay that way until well rooted and I have worked out where I want them. Seem good value if not looking for a very specific root stock for a very specific situation. Good for bees, birds and a nice crumble....custard...thanks!!

Wandered in to Tescos and the wife pointed out that Tescos had an offer on fruit trees so had a conference Pear and a Stella Cherry tree for £12. They also had apples and Victoria Plum in the branch we visited. The roots were in reasonable shape - bit of soil in cling film and bagged so have potted them on and hope we get fruit off them in a year or so. The trees are 4-5' tall so seem a bit of a bargain to me.

Just let us know how you get on as we all like to polish our egos and show how good we are

Yes on the impulse line the fuel is below the carb, the impulse line uses the positive and negative pressures in the crankcase to pump the fuel to the carb. The impulse line can split through old age or get pulled off if the bar gets clamped and needs a strong pull to get it out of the cut. This can dislodge the line and is worth checking out. Not heard of Aumel but Meteor (will post the link again below) are very good and Hyway are a decent alternative if Meteor aren't available. Puch maxi....that takes me back!! Heres the link: - METEOR Piston & Rings Fits STIHL 066, MS660 Chainsaw 54mm 1122 030 2005 WWW.EBAY.CO.UK Find many great new & used options and get the best deals for METEOR Piston & Rings Fits STIHL 066, MS660 Chainsaw 54mm 1122 030 2005 at the best online prices at eBay! Free delivery...

The fella admitted to using fuel mix at least two months since mixing, perhaps longer so there's your route cause. The cylinder looks like it may well clean up. Chemically remove the transfer and then either lightly hone or rub with wet and dry and fit a new OEM, Meteor or Hyway piston.

It may be a worn piston as previously mentioned and when an engine gets hot, compression drops as piston to bore clearances open up. A partially blocked breather is very possible...as previously mentioned, how clean is your air filter? These mesh air filters can look OK but the open areas in the mesh can be blocked so cleaning with a oil based fluid and an air line may help. How is the spark plug colour? Many saw issues can be carb related so worth getting that stripped down and checked out - the gauze strainer getting clogged is an old favourite.

Probably best to get an image up as the hole may be 5mm or 500mm!

Similarly, I once got a 346XP in with......3 top ends, the owner had just kept fitting new top ends not knowing the big end cage had failed. Often difficult to see a cracked cage (unless you have done a few). That 661 is a good deal for someone - I wouldn't rule out eBay as long as it is a good honest description....if I had a 661 that needed work, I would consider it....obviously passing the saving on to the owner. Usually when the cage fails, you get tell tail signs of vertical gouging marks in the bore, dings in the top end and/or port ceilings. Fortunately I have repaired many saws in the way I have described. Most dealers will have more constraints than my business had but have had huge success with most saws - I have found the 660 top end is one of the most resilient for salvaging.

Yup, fortunately the top end is 100% Stihl and looks to be salvageable to me - the piston is toast but does look pretty clean - perhaps the seller changed it....possible. There is another recent thread on this site about a MS880 and we have discussed all about cleaning up the cylinder. What happens is the saw can overheat through old fuel/straight fuel, air leak, bad carb setting etc, the exhaust side always is the hottest side, the piston alloy melts and smears itself on the bore (known as "transfer") sealing the piston rings in to the piston thus losing compression. In your case, I would :- 1) Clean the bore, lightly hone or roughen using emery paper. 2) Fit a new piston from Meteor, Hyway or OEM. (eBay link below) 3) Pressure and vac test (if possible), if not, inspect the impulse line as it is the most likely culprit. 4) Service the carb and then tach the saw as I previously mentioned. The limit cap on the H speed may need pulling but the saw needs to run 12500rpm with your normal bar on the saw. If you do this, the saw will be good and have done this process many times before. You can stick with your aftermarket kit - choice is yours, was it a decent brand? Do you have any idea how the saw seized? Was the fuel mix fresh (mixed under 10 days before use) with a major brand quality oil. Whatever you do, do make sure it isn't over revving once done.

As Chris said, the only issue you have is a weak decompression valve popping out when you don't want it to. The resistance you are feeling is compression and probably isn't being helped if you lined the bore with oil from the rebuild. Personally........ 1) I would have tried to save the cylinder after ensuring it is the original part and not a £25 ebay POS. It is very possible the seller has swapped out the top end with a low cost option which if the case, is a real shame. Take a pic of the top and sides of the original and we will be able to tell. 2) I would have pressure and vac tested the saw after rebuilding it. 3) I would have serviced the carb...I am assuming the new one is a £25 special off eBay....I have found these to be a bit unstable on the idle, OK flat out but very sensitive on adjusting the H & L settings. 4) Finally I would have tach tuned the saw for around 12500rpm...........1000rpm below manufacturers. maximum. My skeptical mind is saying that the seller purchased a non runner, stuck a cheap top end on, did none of the good stuff listed 1-4 so missed the original fault that caused the issue and you purchased it and it went pop. You could get the saw going but the only aftermarket kits I would trust on a saw of this type is Meteor or Hyway. Anything else is a poor compromise unless OEM. A cheap top end will show it's heritage as soon as a 36" bar is stuck on this 660! METEOR Piston & Rings Fits STIHL 066, MS660 Chainsaw 54mm 1122 030 2005 WWW.EBAY.CO.UK Find many great new & used options and get the best deals for METEOR Piston & Rings Fits STIHL 066, MS660 Chainsaw 54mm 1122 030 2005 at the best online prices at eBay! Free delivery...