Sticky chain?

EdStay

EdStay

ArboristSite Lurker
Joined
Apr 23, 2021
Messages
23
Location
Canada
Heya folks,
Got this used ms250 up and running, but still can’t get it in good working condition. Bought it a new bar and chain and using stihl oil to rule out those variables. I’m certain my chain isn’t too tight as I can pull it up enough to reveal the drive link. The chain, however, feels like it’s feeling resistance. When I release the throttle it doesn’t coast to a stop smoothly, rather it rapidly slows to a halt.
Could it be the chain sprocket? When the bars off, the chain sprocket spins free after the throttle is released , but maybe without the chain and bar on it can overcome whatever is gumming it up. I’m not sure that’s the problem but maybe it needs to be lubricated or something.
Any other ideas?
Appreciate the time folks
 
scottr

scottr

Addicted to ArboristSite
Joined
Nov 18, 2003
Messages
2,577
Location
Alabama
It sounds like the drive sprocket is worn and too much chain tension .
With the bar and chain on the saw can you pull the chain around the bar easily ?
 
EdStay

EdStay

ArboristSite Lurker
Joined
Apr 23, 2021
Messages
23
Location
Canada
EAF811EF-7248-4169-ACAB-CC6F6DE3133A.jpeg
 

Attachments

  • F6615FB7-3F84-49BF-8C74-14E610FEE30A.jpeg
    F6615FB7-3F84-49BF-8C74-14E610FEE30A.jpeg
    1.5 MB · Views: 21
  • 7E855114-18FA-43AE-8C18-650B4FC4DDFA.jpeg
    7E855114-18FA-43AE-8C18-650B4FC4DDFA.jpeg
    1.5 MB · Views: 22
Mad Professor

Mad Professor

Tree Freak
Joined
Jul 2, 2007
Messages
10,608
Location
North East USA
I see a narrow kerf 0.050 0.325 bar, and a 3 on the drive link 3/8 chain, those are a mismatch. Probably 3/8 0.050 chain on a 0.325 NK setup

whoops my bad the driver 3 is for gauge........0.050
 
EdStay

EdStay

ArboristSite Lurker
Joined
Apr 23, 2021
Messages
23
Location
Canada
Yes, put the chain on the sprocket and look at how the chain meshes with it, and you will see why.
It definitely sits in those grooves, I just can’t wrap my head around why that would add friction. I’m not experienced with this though so I’ll take you’re word. I’ll get a new sprocket but I likely won’t get the part delivered and swapped for at least a week. I got a big weekend of light clearing coming up. Would it be unsafe to keep this kit running as is to get me through the weekend?
 
Top