spudulike

It sort of makes you wonder what the thought process was? Perhaps some experience of other equipment?? The Yanks call them jugs for a reason! Just means something else this side of the pond.

There is on my McCulloch.......or there was before I removed it!!

The part code is -503 28 90-10 and in stock. I would normally change the complete piston as wear on the piston itself can have quite an effect on the compression but it does look like the ring is excessively worn so may be worth a punt. Piston Ring for Husqvarna 242, 246, 340, 345 Chainsaws - 503 28 90 05 | L&S Engineers WWW.LSENGINEERS.CO.UK Piston Ring Genuine Husqvarna Part OEM No. 503 28 90 05 Suitable for the Following Application's: 242, 246, 340, 345, 356XP, 350, 40, 42, 45, 49, 240, 245, 245R, 245RX, 345R

TBH I wasn't sure if you were saying the plug could come loose or the insulator may blow out or something else. The guy fixed it, that is the main thing and it didn't cost him anything. I had a saw sent in once with the exact same fault. In my case it took me about 30 seconds to find the fault hence what I said! We still love you😉

My experience is measuring at the base of the bore and never seen 40 thou on any machine. That is massively worn!!! 7-15 is fairly typical with 20 on a well used old machine being normal! The cheapest fix would be to get a decent quality piston...OEM, Meteor, Hyway, Episan and fit that making sure it is set to rev as a 350 would be. Check the plating is still good on the bore and lightly hone to accept the new piston.

Like most of these things, info on the workings of the saw will probably be kept back by the manufacturer until they want to divulge them. Only those close to the company will be in the know but am sure it will be interesting!

It does sound like the clutch drum is catching the clutch so a bad needle bearing or a weak clutch spring could be the issue. If you set the idle to something that sounds about right (technical talk for 2800rpm), If the chain creeps, does putting the chain brake on stop the chain but the saw continues to idle OK or does it stall? Don't do this for any length of time as the drum may get hot. My bet would be a weak clutch spring or it may have been stretched/damaged if removed before.

Sorry, I was talking ring end gap clearance and not piston to bore. I have seen some piston skirts shattered down to excessive piston slap through wear. The MS260 was one culprit!

5 thou is very good, 7 -15 thou typical, 20 is getting knackered. Obviously a single ring is more prone to compression loss than a double.

Take the ring off and pop it in to the bore, push it up square in to the bore with the piston 1" up and measure the ring gap with feeler gauges - that will tell you if the ring is worn. Push the piston up in to the bore so the bottom of the skirt is flush with the cylinder bottom and see if there is much rock front to back on the bottom of the piston - a little bit subjective but it works for me!

Open port transfers on that top end - you can see it in the first pic. Not a 353 unfortunately!

The 346 came in two variants, 45cc and 50cc. The earlier with a 42mm piston, the latter with a weird sized 44.3mm. The cylinders were always closed transfer ports. The 350 has open transfers - these will be two channels running up either side of the bore and a 44mm piston. It looks like you may have had a previous owner who got hold of one of these top ends and slapped it on. I have converted a few 45cc to 50cc 346XPs and these have worked out well with no issues. Bit of a strange one and the 350 will not rev anywhere near as high as the 346!

In most cases, after checking the bar oiler hole is clear, it is easier to spin the clutch and drum off, pull the oil pump and pickup pipe off the machine, check the pipe and filter is clear, check the worm drive/pinion for damage to the worm thread and then check the oil pump inlet and outlet holes are clear. Usually a squirt of WD40/carb cleaner and a blast from a compressor will clear any blockage but sometimes you need to work any slug of fine wood chip out with a sewing pin. If this doesn't do it, it may be the oil tank breather but is much less likely. The issue with these Chinese saws is that they use cheap materials and poor design. The above on a mainstream saw may take 15-30 mins, some cheap Chinese saws need to have the engine removed to get to the pump. Good luck.

I was thinking of a local plumber, loved doing the jobs, never knew who he had worked for, how long it had taken, what materials were used and who had paid. Being good and having a skill is just one part of it....a big part but the rest makes it a viable business.

That last bit is good advice. Many guys are good at a job but rubbish at business. They do the job and them another and another but there is no process to start invoicing and chasing payments. A sale isn't a sale without payment in full!! Many hate the paperwork, I don't care for it but I understand the need to keep the whole business process in order.

Excuse me sir, did you say COCKRINGS.....really and on a Sunday as well!!! Who do you think you are? Prince Albert😂

It gets pretty easy the longer you do it. I did have a weird one earlier in the week, big fat spark on the spark tester - jumping at least 7mm + and after swapping out all the main components, turns out to be the HT lead so the plug must have not been sparking under compression.....that was a first and took hours as I had discounted the HT lead being the problem! This one in comparison...piece of p£$s! Your thoughts are the same as mine, the blow-by of combustion gasses around the plug hardens and breaks down the aluminium thread which can then strip out hence what I said earlier about making sure the plug is kept tight. I think you need the award doing the job you do, at least I can abuse my customers....they love it;-)

Pass it on....do a favour for someone else or help someone on their way, and pass on the message, it may make the world a better place.

Damn, it almost looks like I know what I am talking about...... my original post....."It sounds like the spark plug or decomp valve may have come out as even a seized engine will give slight compression enough to tension the starter." One bit of advice and that is to check the plug tightness regularly to make sure it doesn't happen again - it often does. I hope the plug was just loose and hadn't actually popped out as when they do, they often take a few threads with them and that can lead to the thread failing completely. You need to do it up to finger tightness and then compress that sealing washer by half so you get a good grip. Anyway, good result, the dealer should have fixed that every day of the week. Glad it is sorted...Happy Christmas

WTF...either you have completely misunderstood him or he was talking gibberish in a twatish dialect! If the base gasket fails, the saw will still make pretty much normal secondary compression, you will have a big air leak, you may feel the cylinder is moving on its screws and it may not run at all. If you pick the saw up with the starter handle, does the saw fall to full extension of the recoil rope immediately, does it take 2-3 seconds or 8-15? Have you taken the muffler off and looked at the piston? You can take the spark plug out and shine a torch down the bore to look for streaking/scoring on the bore surface around the port. Not being funny but....your saw is 65cc and if you pull it over hard with the decomp out, you will feel it, it is your saw, you know what it normally does. You initially said there was no tension in the starter chord.....in my world that means the engine spins over like the plug is out and that means a bad failure. I can usually tell within seconds what has probably happened and verify the issue for fact in a minute or two. I am NOT bragging, anyone who does this sort of work should be able to do this as many of my customers have witnessed when they hand their saw over and I pull it over and wince at the lack of compression or dodgy noises coming from the saws engine! Checking the compression, checking for a seize takes a few minutes by a tech. Just follow the advice from us and lets follow this through and get the thing going again!!

Lockdown life for you!!

My favorite Gyro..... Anyone feeling hungry and wanting a beer now?

CPC Farnell are a big company, Farnell are a big electronic component distributor and CPC are the domestic side doing computing, gaming, homewares, TV and Audio type products. They are a BIG name but think CPC are perhaps better known in the North as they are based near Preston. I have visited both Farnell and CPC as a supplier to them in the past and have purchased from them with no issues. The axe looks like it has been kicked around for a while. It should come with a plastic guard holder/hook so you can hang it up and it also protects it in transit and for hanging in a shop etc. I got my X27 from Amazon US when you could get them for £40. The teflon coating would have come off if your axe had been used but it looks like the plastic safety cover has been removed and the head has taken a knock. Perhaps a couple of lads in their dispatch department pissed around with it before sending it! I guess it would look like that after its first outing but not good receiving it like this as new. Perhaps ask for some sort of refund to compensate for the damage - probably easier and cheaper for them to do this than organize picking it up etc.

It sounds like the spark plug or decomp valve may have come out as even a seized engine will give slight compression enough to tension the starter. Check these two things first, if the plug has come out, check the thread of the hole and make sure it is still OK as it often fails once a plug has come out under combustion pressure. If it isn't this and your "no tension" is more like not much tension then you have probably left fuel in the saw for a while then cut hard with it and seized it.

Agreed, they are rock hard rubber and split away from the mount after a short use. I tried them once and binned them when the saw came back a week later....absolutely shocking.