spudulike

Try the same when hot as well. It may just be that the carb needs a retune, perhaps a little richer on the L screw. An air leak should affect cold and hot running. These saws can leak air between the top crankcase clamp and the engineered plastic engine cradle. This can often be resolved with stripping, cleaning and resealing with a thicker coating of liquid gasket. I have had a few like this.

You should be able to measure the resistance between the cylinder (earth) and the wire that comes off the generator mounted behind the flywheel. I don't know what to expect but you should get a reading if measured on a relatively high resistance setting...say 20kohms. You could fire it up and measure the voltage from the same earth and wire connection but disconnect the generator wire from the rest of the circuit as you may have a short back to earth. I have seen the magnet on the inside back of flywheels break up (not the coil ignition magnets) and have also seen old machines have the non heated handle flywheel fitted after failure of the original. ADW will have a more detailed angle on this as I haven't done one for a long while but what I have said will prove the generator works and you may have to remove the flywheel to check the magnet or slip a thin feeler gauge round the back of the flywheel to see if the magnet pulls the feeler towards it....but do this away from the flywheel coil magnets. Checking the switch is a straight continuity test with the switch open or closed, the switches are normally sliding contact type making them pretty reliable. The rest of it is metering out the components and wiring

Shame, they were solid workhorses, well built machines if a bit heavy now. I had one I did up and used for a while, nice machine and had the later plastic chain brake guard.

The first question is what is the "sap's" as I have not come across such a chainsaw part. I think you had better re-read your post and make it more coherent.

Black means they are running rich and they shouldn't be fouling up like that unless the carb is well out. Tan, coffee colour is about right and this will come by running a saw flat out in larger cuts for a while.

One issue with this model is that the HT lead can rub on the top AV mount ( the one by the air box) and start arcing on it so it starts cutting out. The machine shouldn't knock out sparkplugs, I once had a FS1E that had a bad helicoil and it didn't transfer heat well and it would melt the plugs but not seen it on a saw. I have seen loose electrodes in Rockwood plugs but a real Bosch or NGK should last for years.

I did wonder myself....many years since I rebuilt a pile of MS200s for him.

The not returning to idle could be an air leak or just a sticky throttle control. If you pop the top cover off, rev the saw and manually push the throttle closed with the linkage on the carb itself. If the saw still doesn't snap down to a decent idle, it looks like you have an air leak. If this isn't sorted, it could seize your saw. The issue may be carb related so worth checking the gauze strainer, diaphragms and ensuring the throttle butterfly and spring are shutting off correctly.

The cylinder looks OK. Get a new piston for it with Meteor being best followed by Hyway and then VEC or Golf. Try to avoid the others unless you really have to use them. You could try using a washer behind the cylinder exhaust flange and fabricating a plug to fill the hole as others have said. You could probably get an aftermarket muffler to replace the worn one. That will be OK.

Most of the compost we have purchased is like mashed up wood chip. Very fibrous, near black and not seen the like before they did peat free compost. If growing from seed, steer clear of the compost made from councils bin collections as we had real issues growing seeds one year and put it down to weedkiller and lawn weed and feed stopping seed germination.

A fella at work had one of the "Red Rocket" CR250s air cooled and red engine hence the name, another "Lad" thought he would give it a go...hell it is only a 250! Came back ashen...white as a sheet - apparently he hadn't experienced anything like it in his time. That was back in the early 80s - it was a bit of a weapon!

Sounds like either the needle valve is leaking or the primer has been connected up incorrectly.

He has.....he killed it

I think MattyF is my go to saw killer bless him. Don't get me wrong, he is a good decent fella and have a lot of time for him but he is HARD on saws...or at least he was during the time I know him. I still remember him working on his 346 on the floor, it sort of looked like a rabid Jack Russel had his wrist in its jaws.

Good luck with that Andy. I think time on a bike sort of gives you a good approach to apexes and cleanest ways in and out of corners....plus a bit too much competitiveness than is probably healthy. Have a great day...don't smack it!

Please forget splitting the crankcases and start using the grey matter. The bar studs have nothing to do with holding the cases together and in doing this, you are just showing your inexperience. The saw isn't running - only a saw with a massive air leak will not run, small air leaks cause other running issues but the saw will fire and run. You seem to have verified that the saw has compression. It is relatively unlikely your HT system is that bad but if you take an old plug and bend the end electrode well away from the centre electrode, you can test the spark over a big gap. If it sparks, you are most likely OK. I said most saws issues are carb issues and that is....because they are. I think you said that the carb had petrol in both sides. It is quite possible that the needle valve isn't sealing off correctly which would stop the saw running, if you have a Mityvac or pop off tester, you can test the valve. If you don't have this equipment, stick a bit of pipe on the fuel union, suck on the pipe and stick your tongue over the end. Your tongue should stick to the end of the pipe and stay there. If it doesn't do this, the issue is with the needle valve. Your compression gauge sounds like a car one which isn't suitable for small engines - many use schrader valves but the ones for small engines have a valve that opens up with very little pressure and that is the difference.

Don't hold back! So you think the saw may not be worth looking at

A damaged crank seal will not reduce secondary compression (compression in the combustion chamber). What it will cause is a leak under pressure or vacuum in the crankcase which may cause the engine to overheat and run badly. Your compression gauge - have you tested that it reads 150-170psi on a good running machine?

I have just worked on a number of 026s and when I have been through the whole saw and the idle isn't good plus the carb is old, I have found MS260 carbs fix the idle issue. Basic rule of thumb, if you can't dial a carb in within 2 mins, it needs sorting.

I think that some 361s had a separate key like in the pic and some were cast in to the flywheel. I have an original one on the bench at the moment and the key is like this....thicker than the usual MS200T, MS260, MS460, MS660 etc but the one on my bench is 100% genuine. The flywheel had come loose hence it being with me.

From memory, I believe they both share the same rear handle. There are so many different variations of the 024, MS240, 026 and MS260 that you can swap many parts. I have worked on old 026s with old original carbs and the only way I could stabilize the idle some was to fit a later carb which resolved the issue. Yes, you could swap the compensator covers out with flat ones but I really can't remember if I have in the past.

That piston is not OEM and the cylinder has those round plating marks on the combustion chamber that I have only ever seen on aftermarket cylinders. The OEM cylinder should have "Stihl" and "Mahle" or "Gilardoni" on it plus the part number. There should be a stamp on a small flat near the plug hole. I reckon this machine is a Chinese copy, probably Farmertec. The decomp shouldn't leak in the out position - you could either lap grind it in, replace it or replace it with a solid plug. Basic engine fault finding is ensuring the saw has spark, compression and fuel....unfortunately that isn't the whole story, the spark has to happen under compression and at the correct time, the carb has to deliver a fuel air vapour but in the correct volume etc. If the saw hasn't run from new, and it looks that way, it may have a manufacturing issue. Good luck!

How did you check the piston orientation? Have you inspected the piston from the exhaust port? I ask as if the saw has seized, the inlet side is often perfect with all the damage being on the exhaust side being the hottest side. When you try starting it, leave the decomp valve out as the extra compression will help. Once the saw is running, it is up to you whether you use it or not. Most issues on this type of equipment are carb related so it is worth taking the carb covers off and checking both voids under the covers are full of fuel.

Good call on cleaning up the cylinder and then fitting a Meteor piston. Also worth looking out for the WTE carb, I used to pay £15-30 for a good secondhand one and was generally well worth the spend.

A friend had a leaky bath and many years after, I was doing a bit of work on their ceiling and the joists under the leak had turned in to something resembling a crunchie chocolate bar. Even if the timber is good I would treat the timbers in something that will kill off any spores otherwise, you may get issues in the future. Your log water content meter will help tell you how dry the wood is. a hammer and screwdriver will prove the hardness of the wood.