spudulike

Mmmm at least we could correct it later:thumbup:

Clean the squish band + piston crown and test again, take 0.5 from the measurement in mm and make a new gasket of this thickness:thumbup:

The clutch won't make the saw bog, you will find the saw revs soaring and the chain speed slowing in the big cuts if the clutch was slipping - same as a dodgy clutch in a car! The clutch would also get very hot. Bogging in the big cuts may be poor compression due to engine wear, overly rich mix on the H screw, weak mix on the L screw, dirt in the carb, old or split fuel line, bad fuel filter or a multitude of other things - also make sure the exhaust outlet hasn't been crushed and if a spark arrestor gauze is fitted, remove it! I am guessing you have cleaned the air filter???

I hope that isn't your ported 026 Rich, it looks a mess to me, bad lean seize and don't know if it is salvageable without some better pics:thumbdown:

Nice one, glad he didn't cut her up with the saw - or Trev the gardener:lol:

Probably the throttle linkage fouling or sticking, other then that it is a typical sign of the saw having an airleak on the vacuum stroke (upward stroke) of the piston so if the throttle linkages are OK then vac/pressure check. If you can get to the side of the carb with it running, rev it to get the saw to show its symptoms and then close the carb fully by pushing the throttle lever closed with your fingers and see if it sorts it out:thumbup:

The 254 in good trim will thump the 137 no problem, it sounds like you have issues though. A tank full of fuel in 5 mins is crazy, where the hell is the fuel going, you should get around 30 mins cutting out of a tank??? I would make sure both the H&L screw are one turn out from fully screwed in. Just turn the screws clockwise till they stop - don't overtighten, and then undo them one turn each. This may be your only problem. Try this setting - the idle may well need adjustment and let us know how this goes. If the saw is still iffy, you will need to make sure the saw fast idle start mechanism is working, it is a little plastic lever that engages with a small pressed lever on the throttle valve shaft - I have had issues here before! Easiest way to check this is to pull the choke on, push it back to off and then open the throttle slightly and you should hear a small click:thumbup: No click and the thing will need inspection as to why it isn't working. When you start the machine, on the fast idle setting, the saw should race with the chain spinning, if this isn't the case and the fast idle is engaging properly, it is possible that the L screw needs leaning out a little so try turning it in 1/4 turn. Good luck, let us know how you get on - I know my way around these machines well having refurbed on and run it for a couple of years - very decent saws IMO

All interesting stuff:thumbup: Guess I do most of what I do using kit I have put together myself on a shoestring, never thought I would use it as much as I have though and don't mind reinvesting cash on useful tools:thumbup:

Is that like my sparkplug with it's electrode bent open so the plug gap is about 4mm:lol: Nice shiny tools Barrie - I am making a Christmas list:thumbup:

Make them go faster:thumbup: Unfortunately, you cant open up the ports as much down to the piston design but gains are always available!

And that Rich is why we like ported saws - did you hear any bogging on cutting that size wood with a 357??? Didn't think so:thumbup: Nice one Martin, you must be happy with it cutting wood that diameter:thumbup1:

The chain may be stretched unevenly or be very loose due to wear but everything else should be OK - slap a bit of thick oil or grease on the sprocket bearing for good measure!

Ebay is the best bet for parts! If you are interested, I have a runner that either needs TLC or stripping for spares, I purchased it to do up and sell but that is a distant dream:blushing: PM me if you want a price on it and a few pics!

Carb cleaner and a lighter should see it off......on the other hand, don't do anything so stupid:lol:

I keep blowing the schrader valves up, they are soft opening ones, needed on this type of kit and they don't like 200+psi of the pop up piston on the 357XP - given up testing it now:001_rolleyes: Other than that, good bit of kit!

Just make sure the bore is clean on reassembly otherwise it will kill your new rings:thumbdown:

Around 2 cubic metres since end Sept, small 4.9kw Stovax burning from around 5.00pm - 10.30pm.

Firstly, is the carb on factory settings on the L screw - that is one turn out from fully seated? If the screw is over 1 1/4 out then you may be compensating for an air leak in using an over rich setting! The symptoms you have could be over rich or over weak carb settings, air leak, holed impulse line, worn carb parts, worn carb, bad fuel line, badly positioned fuel line, bad fuel filter, bad tank vent and the list goes on. I usually strip the saw down and do a pressure and vac check as it checks out so much very quickly, I also pressure check the carb to check the needle valve and many more checks. After doing this, saws usually normally throw in the towel and work. One simple thing to try is to put a known good carb on the saw and see how it is! The 020 carb is more reliable than the MS200T - it should have the H&L screws very close together!

The 010 has an external pumping button you can push, not sure if it is to free the mechanism or just to give the chain a little extra oil. Funny enough, I was workiong on the same component on my 009 and fitted parts of an 010 I had parts from a few years back. Flushing the tank with fuel is a good idea at the end of the season - I would personally avoid some bio oils as they can become very gloopy.

Diamond files where accessible and then medium to fine grade abrasive paper. Using a grinder is a bit savage IMO!

On the subject of ported saws and lifespan, a guy in the States did a comparison before and after porting on a Stihl 026 and found it actually ran cooler as the exhaust gasses were being expelled faster. The crank, crank bearings and small end are usually pretty bullet proof and will take the extra power. The ports, if opened up too far and not bevelled correctly may wear the rings but if you stay within the correct paramaters, the ring and piston should not wear considerably faster than standard. The saw wil put extra wear and tear on the bar and chain - bit like a powerful car and tyres but thats life! I have ported a number of saws and so far, so good! I have read much on the subject, the US go in for it much more than we do in the UK and haven't read any detrimental comments about a woods port killing the life of an engine - full race tune is a little different! Just depends on what you want out of life!

OMG:scared1: TBH, the first one is the worst, you just need to understand how the engine works and what you need to do to get it going better. I certainly don't know it all but I know what I CAN do and also, what works! I haven't started playing with timing wheels....yet, but do open up ports and transfers to a point the saw gets somewhat lively:thumbup: If you do get the bug, PM me and I will give you a few tips that may save you shagging the engine and making a big mistake:blushing: That is an offer to a past customer rather than to everybody:001_rolleyes: The new P&C on a 357XP is somewhere near £240 so would be a tad embarrasing if I had cocked up the first one:lol: I get a good feeling about this one, the last one went to Burrell who has been abusing it ever since and has been his trusty sidekick - they are infectious - even my hedge trimmer is now ported!

Sorry, it is done, all repaired bar fitting a new chain brake handle! Been repairing this MS200 and also started to clean and port a 357XPG - yes, it has heated handles:thumbup: I like doing these saws as the inlet and outlet ports can really be opened out. From the pics below, you can see how far the exhaust port can be widened by the red guidelines! The crankcase has stuffers on the lobes that increase the transfer velocity, one of the few saws that have this technology on them. The transfers have been blended and enhanced, the inlet has been widened and the lower transfers are awaiting modification! It will probably run up to 15,000rpm when finished:-)

Two pieces of wood wedged between the crankcase surface that joints the cylinder and the bottom of the piston skirt, make sure they are hard against the con rod and use them to lock the piston in place - it has worked before:thumbup:

I reckon at sometime the chain brake has been put on and the side cover removed and them been put back on causing the binding and the eventual failure of the brake band. Reckon once the band is replaced and the brake released, all will be good. Barrie - can we get a Youtube vid of the hat eating - I just hope it is one of those leather cowboy jobs I see at country fairs - now that would be a bit chewy:lol: