spudulike

I use a little Ferm unit with no air tank - it is basically a 1.5hp electric motor cranking a small engine with a pressure relaease valve plugged in to the plug hole and an air gun attached to this! A bit like this one - https://www.google.co.uk/shopping/product/3589325883985181493?q=Draper+air+compressor+1.5hp&hl=en-GB&gbv=2&oq=Draper+air+compressor+1.5hp&sa=X&ei=UF6XU5L5BOrW7QbC_oD4CA&ved=0CC4Q8wIwBQ The good thing about it is that you just turn it on and bingo, 2-3 seconds later you have air - the bad thing is the air only lasts for a second or two but is generally enough to blast crud off saws, is effective and no service cost:thumbup: It is only of use with an air gun and for inflating tyres - you cant run tools off it or spray guns, sand blasters etc!

Get some semi fine wet and dry, give the area a rub around the bore and not up and down, re apply the acid and if it froths and goes white, do this until it stops and repaeat until it won't fizz. Once this is done, use the semi coarse paper to get rid of the residue and the fine 400 grit to finish it. You need to get this surface nice and clean before fitting a new piston.

extra pin rims/sprockets are usually fitted to larger saws running small bars or ported saws where the extra load of the larger sprocket is easily accomodated with the torque of the saws!

Whats on my bench......tooo much:001_rolleyes: Just finished porting and repairing a seized 357xp, started porting a 372XP and have a troublesome 365 Husky - the saw has been thoroughly gone over but the carb is acting a little strange in so much as the sweet spot on the L adjustment keeps moving. I have boiled the carb in the ultrasonic cleaner and hope it sorts out the suspected leaking H speed check valve!

So the long and the short is that Stihl released a saw that........wasn't quite ready yet:blushing:

Nice with a diamond burr:thumbup:

GHS has a compatible P&C kit for 50/51 saws and they both share the same crank case part number do reckon a 51 kit will fit buy check both saws stroke first. I do think that plating will be ok, it may be thin but it is also bloody hard:thumbup:

If it is around 15% HCL, it is fine. A bad seal won't smoke and the only way of testing is to use a pressure/vacuum gauge. If the seals etc are leaking, the saw will seize again! Fitting new seals is a case of removing the old one and driving in a new one. No crank case splitting needed:thumbup:

They are one of those saws that are not worth a fortune - it only starts getting interesting with 070, 090, 076 and Contras. You can do it up, you should learn something but IMO, you wont pass a 357/361 to get to it:lol:

The cylinder looks like it will probably come back, you need to find some caustic soda (Sodium Hydroxide) or acid Hydrochloric is good) and then give those damaged areas a wipe over with some wet and dry paper and use the chemical to etch of the aluminium - it should fizz well when doing this. When it stops fizzing, clean it and rub it over then try again - if no fizzing happens. yoa have converted the metal to much softer aluminium oxide. You can then rub the black shyte off with around 180 paper and then 400 to finish it. I do use a cylinder hone on the bad ones but do it extremely lightly and find it beds the piston down well but if you use this method, don't go mad as the plating is thin on these cylinders. The crank seals and ancillary rubber parts can only be checked with pressuresing and creating a vacuum in the crankcase, the play in the crank isn't a way of checking this. The most common failure is the impuse connector from the carb back plate to cylinder and also the clutch side seal.

The carb shouldn't have limiters on them so turn the H&L screws all the way in and turn each screw one turn out and try this setting The idle may need adjustment and check the plug colour after 1/2 hours of use! Don't go any less than one turn out on the H screw, it may seize the engine if the saw over revs

The cylinder may be ok, I have a 95% success rate on them but it is a bit of a job and takes a bit of know how! The aftermarket stuff is what you pay for,some OK and some awful. The Hyway stuff seems passable but I try to salvage the OEM part and fit a Meteor piston if possible.

Its toast bud:thumbdown: That has laid down a coating of Piston aluminium on the cylinder and will need the cylinder salvaged if possible and a new piston or a new cylinder and piston. DO NOT just replace the piston, the cylinder must be that smooth, you feel no ridges etc with the pad of your finger - if you can, it will take the piston ring out on the new piston! The reason for failure also needs investigating - common causes are bad/old fuel, leaking crankcase seals, split impulse/inlet manifold and incorrect H screw carb setting.

Not another bloody KM100 - just buy 2 stroke Ed, you know it makes sense - ask Martin, he will tell you:thumbup:

Whats on my bench: - too much for me to move now:001_rolleyes: Loook lads - turn the tap off - I have enough to keep me busy now, it isn't big or funny:001_rolleyes: A load of saws to port, a raft of toppers on their way and a couple to "de-seize"!!!!

I keep meaning to make one......one day:001_rolleyes:

Remove the muffler and take a look at the piston through the exhaust port - if the piston looks like someone has taken a coarse file to it and left it with bad vertical scoring, the saw has seized, if it is OK then lets look at the issue again!

I have used the Stihl one for years, had them slip every now and then but they are generally good. Zi use rope on Huskys when the clutch won't spin off easily as it stays in place when tapping on the clutch!

Mmmm, nice, did the cylinder survive? Rich had one like that and I said to raise and re-bevel the exhaust port - you may get away with a custom or no base gasket to get the timing back to normal....on the exhaust anyway:thumbup:

Those plastic ones are bullet proof - I always use them and rope as a backup:thumbup:

The earlier type get covered in crud and then you get the tan venting issues you are talking about, the replacement one is like the 346/357 one and is a sintered metal one in a plastic carrier that has a rubber hose pushed on to it venting in to the air filter manifold.

The 350 and that series of saws has a two part push in breather - like a small disk followed by a larger one that push in to place - I can't make out your image but it will be next to your fuel line. Garden Hire Spares or Green Stripe will do them - part 503 60 04-01 and 501 62 98-01

The clutch shouldn't slip which was one of the things I was getting at. As a saw bogs down, the revs die and when they get low enough, the centrifugal clutch doesn't push on to the clutch drum so hard and it slips. A saw on full bore shouldn't get clutch slip, if it is, check the weighted clutch shoes haven't worn below their limit. A look at the gap between the clutch shoe and the drum should show you if the clutch is worn, a big gap = wear:thumbdown: Sounds like the saw needs a bit of TLC!

I would like to see how the compression gauge was connected to the "exhaust port":001_rolleyes: 120PSI is low, too low IMO, these saws don't have loads but 140+ would be needed for it to run. As mentioned before, if the piston has been changed, why was it? Had the saw been seized, had all the aluminium transfer been cleaned off the cylinder? Is the top end aftermarket, is the plating in good condition - has someone had a go at it with a hone? The compression needs to be sorted to get this baby to fire:thumbup: