DIY MS460, first run and carb. adjustment.

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It sounds great, it needs an easy start on it like my ms251c, really helps alot. why so much trouble starting?
The kit carburetor that I'm using at the video is leaking fuel in to the carburetor due to the pressure that evolves in the gas tank due to temperature and shaking, so basically the saw gets flooded between use - I guess.
I have ordered an OEM carb for it now.

But I also have a Taiwan made (New West, similar as Hyway) big bore Nikasil cylinder and piston on it, the cylinder is really nice and I have mounted it with no base gasket to get increased compression - and it really have a significant compression. As far as I know this particular saw have a considerable compression to begin with, probably along with a pretty advanced ignition (it fires before the piston is at it's top position). So if its a lot of fuel in it and it backfires you certainly doo feel it in your arm/elbow/shoulder. Compared to my big bore Husky 372 build I don't even consider using the de-comp valve on it because its so easy to start, and thats at 52mm / 76,5cc, no base gasket and a Hyway pop-up piston.

However, if you look at the last start I do on the video (at about 7:30) the saw have just run momentarily ago so its not flooded, and you can see the start is absolutely manageable when using the de-comp valve and a firm decisive pull.
 

samaritan

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The kit carburetor that I'm using at the video is leaking fuel in to the carburetor due to the pressure that evolves in the gas tank due to temperature and shaking, so basically the saw gets flooded between use - I guess.
I have ordered an OEM carb for it now.

But I also have a Taiwan made (New West, similar as Hyway) big bore Nikasil cylinder and piston on it, the cylinder is really nice and I have mounted it with no base gasket to get increased compression - and it really have a significant compression. As far as I know this particular saw have a considerable compression to begin with, probably along with a pretty advanced ignition (it fires before the piston is at it's top position). So if its a lot of fuel in it and it backfires you certainly doo feel it in your arm/elbow/shoulder. Compared to my big bore Husky 372 build I don't even consider using the de-comp valve on it because its so easy to start, and thats at 52mm / 76,5cc, no base gasket and a Hyway pop-up piston.

However, if you look at the last start I do on the video (at about 7:30) the saw have just run momentarily ago so its not flooded, and you can see the start is absolutely manageable when using the de-comp valve and a firm decisive pull.
Just how does a de-comp valve work, if it relieves pressure in the cylinder, how then does it fire?, wouldn't there be no compression?
 

samaritan

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Here is the video of my DIY Husky 365/372 build, I didnt use the de-comp valve even once in this video:

Nice! I just love the sound of the idle. im putting mine back together, and waiting for a few parts, im keeping my fingers crossed also. I like your log holder, you should patent it, if you made it. What are you gonna do with all those slices? kindling I guess.
 

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What are you gonna do with all those slices?
I eventually collect and dry all wood I process for firewood, all those end knobs and odd pieces, I put them in firewood bags, dry them and save them for a cold day. I dont use electric heating in my house except the hot water tank and the floor heating in the washing room.

That particular log have been a couple of years on the wood floor though and I dont want too many wood eating bugs in my firewood stack beside my house.
 

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Just how does a de-comp valve work, if it relieves pressure in the cylinder, how then does it fire?, wouldn't there be no compression?
The de-compression valve ease the compression when you pull the handle but it pops out when the engine fires, it makes for a soft and easy start.
Your MS251 don't have one? My MS241 have it but I never use it, because its not that hard to start and I like the firm feedback from the saw. The MS460 BB is just a little too firm sometimes though...
 

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The de-compression valve ease the compression when you pull the handle but it pops out when the engine fires, it makes for a soft and easy start.
Your MS251 don't have one? My MS241 have it but I never use it, because its not that hard to start and I like the firm feedback from the saw. The MS460 BB is just a little too firm sometimes though...
No my ms251c doesn't have one, but it doesn't need one, it starts real easy with its "easy start" feature
 
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