bluehemisphere

Thanks Shane. I'll check that too...

Thanks for the advice everyone. Yes, the brake was off and yes, the chain was the right way round. Have double checked the bar groove, and it's fine. Nose sprocket is fine. Chain runs freely around the bar when not attached to the saw. Chain-wise, I actually bought a new chain and tried it but alas, same problem. As Andy said, it could be an internal problem. The drive sprocket spins fine under throttle when no chain is attached. But as soon as the chain is on there and taut, it won't turn. SHOULD I be able to turn the chain by hand easily when it's taut? (I'm going for a 3mm gap at middle of chain tautness) Dan, I can't see any needle bearing. Maybe I need to take the sprocket off. (Which I tried to do but the hex bolt holding it on is so tight I can't even budge it. Is it a left hand screw thread?) Thanks again...

Hi everyone. This is my first post here. I'm a landscaper who uses his chainsaw rarely. So rarely in fact, I only have an electric chainsaw. Yes, I said the word that's probably banned here. I only use it for small parts of my job. For real tree work, I call my tree surgeon! It's a Black & Decker GK2240T. ANYWAY. I hit a nail in an old fence post I was chopping last week, the saw jammed nicely, so I presumed I'd find bits of nail under the cover and the chain to be all mangled. But it wasn't. Everything seemed fine. I took the chain off, gave everything a clean. But now the chain won't turn. The throttle works fine. The drive sprocket spins freely when no chain is attached. And it actually drives the chain when it's really loose. But as soon as I tighten it to how it should be, I can't even move the chain along by hand. And when throttling, the motor will run, but it won't engage the drive sprocket enough to turn the chain. I've looked at the bar, and it doesn't appear bent (by eye). The nose sprocket turns freely. I've cleaned out the groove in the bar, and it doesn't look pinched anywhere. The chain doesn't look visibly damaged as far as I can see (but besides the blades being blunt etc I don't really know what to look for) Any advice? If I can't move the chain by hand when tight, does that say something obvious? Do I need a new chain? New bar? Any help would be much appreciated. And I know that by default, having an electric saw makes me a bit of a joke here, but I humbly and honestly look up to you guys for your expertise. Thanks in advance. Jon