bmp01

Fek, I've jumped to the wrong conclusion then. In my defense its not black it's navy blue (compare to the ht lead in picture). Certainly not bright blue though, Google educated me on the shade of blue for a 'blue' coil. So remember I have a 3mm dowl pin in the flywheel where the original key used to be, I'm checking what I have; not starting from a complete unknown. Finding TDC, degree wheel fitted loosely to f/wheel, exhaust off, piston crown below top edge of exhaust port. Drill blank in the gap, rotate crank to cause contact - note angle on timing wheel. Rotate engine through BDC, cause contact in other direction - note angle. Hold crank still, rotate degree wheel to get equal angle before and after TDC. Repeat umpteen times to check, recheck blar, blar. I picked the top edge of the top lamination on the coil for the above. I just marked the flwheel with TDC, 5,10,15,20,25,30 DEGS BTDC. Degree wheel off, engine rebuilt, engine started, starter cover removed while running and strobed the result. Pictures on next post.

That looks like the right coil Spud. It's done all of its advancing between 0 and 3000 rpm, just 9 degrees, flat timing there after. Don't know why I saw 30 degrees difference between 1000rpm and 3000rpm. Also no limiter acording to the data.... I wonder if I've been caught out by shades of blue and the saw needing a retune now the airleak is fixed ??? Tomorrow... Googling SEM and AM44 also throws up a hit on acresinternet.com for the 394xp which they say uses the SEM AF44 coil. Date code on my coil is 2007 W47 (a bit late for a 394 part?) My 395 is an 2008 model - those 2 dates fit together quite nicely. htb - thanks for the offer, not sure if you'll be able to see the part number without removing the coil though . See picture, the part number info is below the coil laminates when fitted.

Thanks for the that Spud, next time you have one in then. .... Checked the coil and rechecked it's behaviour this morning. First thing, it's blue, so that's a limited coil. Part no on the coil 810 204 16 also has SEM and AM44. The Americans think it should be a black unlimited coil. L&S Engineering list part number as 503 63 98-01 Second thing, (with this coil) from idle (2800rpm) upwards it's fixed timing. Retarded at cranking speeds (think battery drill cranking, spark plug out, ~1000rpm) by 30 degs or there abouts. And yes the tach and timing light go beserk as it starts misfiring. ... Edit - I've had no luck identifying the coil 810 204 16 online, no idea what its from.

Love it ! Absolute classic ! ?? Yeah, wasnt really expecting exact degrees, it was more of a summary statement (coming back to timing question) having resolved in my mind the way forward. Up till you mentioned the piston stop thing I hadn't really seen how to change the timing by an accurate amount (or keep it the same). In my mind I'd lost all reference once the flywheel was off, so thanks for that. I think I'm shooting for around 24-26. As you say 19 is too low, I was a little disappointed when I measured that's what it was. 30 has me twitching a bit and well y'know, I'd like to think I've gained turbulence and flame speed with the combustion chamber I have (wide squish band, 0.50mm clearance). But I will, without a doubt, be listening for those 'don't fxxk with me' noises. Too much time into this saw to nuke it.

Chap said JB Weld flexible gasket. Looks like JB Weld are putting their name to a few other products these days, flexible gasket should be ok providing its compatible with fuel.

Thanks for the detailed reply Spud. I don't think there is much chance of a comparison with a standard 395...I've only ever seen one, that 'one' came home with me ? ? It's a thought though - comparing to std. I think I only need a standard flywheel - if the comparison is done statically I can get my saw locked up against an accurate piston stop swap in a standard flywheel, marking position, swap to my flywheel on and see how it lines up. Don't even need to torque the standard flywheel up. But let's say I'm happy with what I know about the timing as it is, let's say it's 19 degs BTDC. If I do a similar thing, accurate piston stop and mark the relative position of flywheel to housing before disturbing the taper. Then even after I've disturbed tbe flywheel I can get the piston stopped in the same place and I can rotate the flywheel to align the marks. Even better, I can also retime it (say) 5 degrees by moving it 5 mm (such a happy conversion). Soooo, back to the timing question......

With the coil I have on the saw it's fixed timing at idle and above. No idea if it's the original coil, saw was secondhand when i got it, I should go and check part number on coil though - I'll do that... Testing was done the same as the video, find tdc, mark flywheel and casing. I then marked 10, 20, 30 degrees of advance on the flywheel so I could read advance directly. Removing flywheel cover while engine was running was surprising easy, but you need to be precise and deliberate with removal. ...

Yes, cast in key. It left a witness in the flywheel taper after it departed. I used a ball nose cutter in a Dremel to very carefully add a round groove into the flywheel. A 3mm pin is then used as the alignment feature. Accuracy was in the order of 0.25mm (magnifier deployed etc) but even then it's at a very small radius so that could be several degrees. I've also lapped the flywheel onto the shaft for maximum torque capability (spoken about quite a lot on the American site's and copied from 2 stroke racing bike engines), should be better than the original engagement. Not blowing the engine up with too much advance is at the forefront of my thinking but equally running retarded from optimum will leave a lot of heat in the exhaust gases (and presumably piston, cylinder )...

Thanks chaps, I'm sure Spud will have some thoughts on this and hope he will comment on the thread when he gets a chance, no need to drag him away from his paid work just yet.

Simple question, what ignition timing advance would you run on a tuned 395xp ? Except its not that simple is it, because you need to know what tuning has been done...ok, well briefly, Muffler mod, gutted internals with twin outlets Transfer ports opened out at the entry. Inlet port cleaned up to remove flash line. Exhaust port raised slightly. Squish band machined 0.45mm Cylinder base machined 0.8mm Base gasket 0.25 (std is 0.5ish) Squish is 0.5mm after all this, compression pressure - dunno, cant pull it over without deploying the decomp valve. With decomp open I get 100psi. Ran pretty strong with standard ignition timing but started to behave weirdly after a good long run (its a milling saw), with the idle speed unstable. Air leak. Replaced the crank seals. Inspecting the old ones - the flywheel side had been leaking, sawdust between the dirt lip and the sealing lip, sawdust inside the seal and on the face of the b/e bearing. Clutch side seal in contrast was nice and clean. I'm happy to have got away with that (air leak)... not so happy about stripping the key out of the flywheel though. 100% sure flywheel was seated and torqued up properly. My mistake - I think - was not degreasing the crankshaft taper... New flywheel is 200 quid so that's not happening. Cutting to the chase, timing light says I have a tad under 20 degrees of advance. Given the high compression of engine it might be I don't need huge advance but everything I've found thus far suggests 25 - 30 degrees BTDC. Comments? Thanks, bmp01

Admire your tenacity mister ! I suspect it's the carb somewhere , from what you are saying about fuel consumption, black plug etc. Have you checked the second butterfly is opening at anything above closed throttle? As you've had it apart you'll have spotted the second butterfly/port only supplies air to the cylinder (no fuel). This second port is more than double the area of the small fuel/air port - if it wasn't opening you'd get massively rich engine and little air flow to the cylinder, so no power. I'd guess it would misfire something chronic. Could also be a bad coil with timing gone bad or my current favourite topic - sheared flywheel key giving messed up timing. Plenty other options...

Sounds familiar, is this the same saw with the same low power issue posted about on 21/11/19 ? https://arbtalk.co.uk/forums/topic/118088-stihl-ms-211c-with-low-compression-issue/#comments I think you're going to need someone in the know to have a look at it. You might have more than 1 thing wrong with it which will make it next to impossible to diagnose remotely. At a push a video of it running and cutting might help. Need to see the saw dust chips too.

Compression seems ok then. I just went and checked my 211, exactly as per your description, takes nearly 30 seconds to completely unwind the starter cord. Personally I'd still check the piston. If it's the bar or chain as suggested how new / old are they ? Is the chain overly aggressive, rakers set too deep ? Is it oiling the chain, bar getting hot ? Has someone changed the sprocket to 7 tooth ? Simple engine things, swap spark plug, air filter clean, checking fuel lines, fuel tank breather, carburettor tune up. Beyond that its anyone's guess - there's no substitute to seeing the misbehaving saw first hand. bmp01

As Spud says, pull the muffler off and check piston for a part seized piston. Piston can seize in a couple of seconds during a single run, so just because it was fine when you last saw it, that's no guarantee its still good. If the saw ran ok (post rebuild) and then started messing about that's the first place to look - no point risking further damage for the time it takes to do a quick check. Your saw has that easy start contraption on it I think, which is a shame - it means you can't do the quick and dirty compression test where you pick the saw up by the starter cord. bmp01

Thanks for replies. Watching the guy use it - it looked like a handful. He was plunge cutting with it a couple of times, didn't kick-back but you could see he was fighting the reaction forces. I guess the hook thing on the bar is intended to help with reaction forces, looks like it would be in the way most of the time though.

Just stumbled across this, new one on me. Does anyone know the history and application of this type of saw. I came across the picture then had to watch the video of a beekeeper chap using it. Picture attached and video at: youtu.be/NnMELNP7mB0 thanks, bmp01

As others have said, lovely wood. Just got to question the logic of the world (again) if such items can be had for "beer money", (Lot of beer mind you). Plenty of people making beer these days, seems its quite good currency .... bmp01

Hi, Well, it made me smile - I like it ! I expected a 1 pull wonder followed by endless resetting etc, etc, so I think that's quite an achievement to have created a thing which presumably keeps pulling until the user switches off the drill. Operational concerns, - Mechanical reliability of the starter mechanism on the tool you're starting - I know some people just keep yanking on the cord but really the first stage of the pull should engage the starter pawIs before the real tug of war begins. And that's after you've found the correct starting point. - Structural reliability of what ever your starting device is pushing against, you have to remember if a tool can be misused it certainly will be, I can imagine someone leaning it against a fuel tank .... - Safety issue of the machine you're starting jumping about at start up, there's good reason every manufacture of chainsaws states the user must hold the saw firmly when starting. Starting on the floor requires foot through back handle and hand holding forward handle.... - User response time after engine start up is shockingly poor, you need to be able to operate the controls of the machine as soon as it fires up, crucial for a chainsaw. Sorry, that seems quite negative, I think it's a great achievement to have got this far but equally I'm not convinced of its practicality in the world of chainsaws. bmp01

Thats a result, well done, and thanks for posting the info and solution. My only concern is that the clutch drum has been moved a mere 1.00mm and i had imagined it needed something in the region of half the width of the brake band to fix it. But, you've been into it pretty thoroughly and tested it so i guess that's all it needed. Nice one. bmp01

So what, you been on holiday or somethin' ? ? Thought I'd seen some posts on here during the summer, but in hind sight I must have been searching some old posts. ... on the XP395, they're still there of course, yonks old.... Brains going, going,.... going ... and gone.

What's going on here then ...looks like there's been some serious editing - i mean deleting of posts - in this thread ? 12 March jumps to 27 Sept....

That clarifies it nicely. Does sound like the clutch drum is in the wrong place relative to the brake band or the drum is wrong. Trouble is you'd expect the clutch drum to be wearing through the clutch cover... Worth swapping your mates clutch drum over to your saw ? (not a 2 minute job with outboard clutch).

As you've swapped plenty of parts and I'm assuming you swapped your mates clutch cover onto your saw (not clear) and that behaved the same then I'd guess the reassembly of the clutch cover onto the saw isn't going quite right. Is the clutch drum catching on the brake band at the top ? Brake band might now be distorted too. Is the clutch drum a genuine one and definitely the correct one? Might be better to post this in the chainsaw section. .... Good luck with it. bmp01

Same. Picked it up as a non-runner, out of curiosity mostly, split hoses in this one too. Next time I attempt to use it there'll probably be something else to fix ?

Just back from holidays otherwise i would have replied earlier...... This situation is very similar to the one i was faced with just recently, link: https://arbtalk.co.uk/forums/topic/116207-ms200t-valuation/ Advertised mine at 400, got the usual "what will you take for it, mate" reponses plus genuine interest on here. It went for asking price to a local guy as he could collect 'next day'. Plus he got to inspect and test it, I like old fashioned cash for goods arrangement. Yours looks like 400+ from pictures - the right price is what people will pay for it, nothing else matters.