Stihl MS200t Chain Sprocket Cover stuck

[hangfirew8]

I lucked into a beat-up MS200t at a yard sale this weekend, it looked rough, real rough, but not much money so I took a chance. Chain is rusted stiff, handle is broken, and one side packed with dirt- it looks like it was dropped from a tree and then tossed into a shed for a decade, as-is.

Anyway, I got one side off and can turn the engine with a socket, turns smoothly and good compression (from the feel of it). So, it should be worth throwing some parts at it. But for the life of me, I can't figure out how to get the Chain Sprocket Cover (right side plastic cover) off the saw. It seems like it is glued or bolted on about center, right over the sprocket. From reading the parts list and the manual the only thing holding it on should be the big nut "Collar Nut M8". That's off but the cover is not budging. I can see the brake and it is not seized to the sprocket drum.

Am I missing something obvious, not so obvious, or is this thing melted or glued together?

Thanks!
HF

 

[k5alive]

look where the bar nut is, theres a metal spacer it could be pinched up on the bar stud threads

 

[Jumbo Jimbo]

All I know is that the hand guard is attached to that cover and if that is stuck it probably won't come off. Other than that the only other thing that should keep it on is the bar nut.

 

[paccity]

brake tripped?

 

[ckelp]

brake tripped?

i think you nailed it on the head

something happened today when a guy said i sold him a POS saw. when i looked at it he fried the crank:bang: i told him that i'll take it for a parts saw..

 

[BlackOakTreeServ]

brake tripped?

This was the first thing that came to mind....make sure and un-trip the chain brake, then give it a try.

 

[hangfirew8]

Thanks, everyone, I did try moving the chain brake both forward and back, that didn't help, but it still might be the problem. The chain brake handle is broken, so it could be stuck in the internals, even though I'm moving it on the outside.

I'll take another crack at it tonight, and see if I can manipulate the chain brake mechanism with a screwdriver or probe.

HF

 

[hangfirew8]

look where the bar nut is, theres a metal spacer it could be pinched up on the bar stud threads

Thanks, I can move it up and down freely a few threads, bending the cover doing so. The stuck point seems to be a little further back.

HF

 

[paccity]

if you need a pic of the innards of the mechinizem i'll take one later. theres a dog bone looking peice in there that break often . prob broke and jammed when it took the hit.

 

[Zippy]

Here's some pics

Here's some pics from inside the clutch cover - hope it helps.

 

[Dan_IN_MN]

if you need a pic of the innards of the mechinizem i'll take one later. theres a dog bone looking peice in there that break often . prob broke and jammed when it took the hit.

#3 is probably what paccity is speaking about.

Good luck with your saw! Take your time.....so you don't break more than already broken.

 

[paccity]

depending on what is screwed up in side. first pic is re least sec is tripped third is where you put screwdiver in to push to untripp.

 

[hangfirew8]

Wow, great pics, thanks paccity and Zippy! They are going to be a great guide for reassembly. This is an awesome forum!

I just spent some quality time with the saw, and made no progress on the sticking point.

The stuck point seems to be exactly where that metal rod on the cover inserts into engine casting. I guess its an alignment pin. It is not visible on the parts list because the perspective hides it from view, so I didn't know it was there until I saw paccity's pictures.

I'll try the screwdriver trick, but I'm 99% sure it's that cover's metal rod stuck into the casting. The brake band isn't that tight on the wheel. If the pin is really the sticking point... not sure what I can do. Maybe drill and slide hammer (dent puller)?

HF

 

[Zippy]

Not sure, but if you take the starter off can you put a long screwdriver or similar through from the flywheel side past the cylinder and push against the sidecover where the metal dowel meets the cylinder?

If you can - you might be able to tap it off?

Just a thought.

 

[Dan_IN_MN]

Wow, great pics, thanks paccity and Zippy! They are going to be a great guide for reassembly. This is an awesome forum!

I just spent some quality time with the saw, and made no progress on the sticking point.

The stuck point seems to be exactly where that metal rod on the cover inserts into engine casting. I guess its an alignment pin. It is not visible on the parts list because the perspective hides it from view, so I didn't know it was there until I saw paccity's pictures.

I'll try the screwdriver trick, but I'm 99% sure it's that cover's metal rod stuck into the casting. The brake band isn't that tight on the wheel. If the pin is really the sticking point... not sure what I can do. Maybe drill and slide hammer (dent puller)?

HF

Would it be possible to post a pic? They speak 999 words! :msp_biggrin:

 

[Zippy]

You can see them in the top two pics of post no. 10 - the metal dowel and the hole receiver in the cylinder wall.

It makes sense - probably got bent during the impact.

I guess the only way off is a bit of brute force but you'll want to do as little damage as possible.

 

[Dan_IN_MN]

You can see them in the top two pics of post no. 10 - the metal dowel and the hole receiver in the cylinder wall.

It makes sense - probably got bent during the impact.

I guess the only way off is a bit of brute force but you'll want to do as little damage as possible.

I see the dowel you're talking about.

I personally don't see how that would get bent....but...I haven't seen one of these little guys after they've been dropped either!

I think it would be good to see the condition of the cover and saw in general.

 

[hangfirew8]

I think it would be good to see the condition of the cover and saw in general.

OK but don't laugh... OK go ahead and laugh... but keep in mind I've only got $10 in it so far, and the piston moves smoothly with compression. I chipped the side of the exhaust trying to pry off the cover, also most of the cracks on the cover are from prying, but the chain brake handle dislocation is as found. I got the bar off by prying the front of the cover enough to pull it out, the chain broke, no loss as it needs a new bar and chain anyway.

Also keep in mind it is very cleaned-up from the state I found it in, the saw was covered with bird dirt (must have been a nest above it in the shed) and packed with rotted sawdust in the pull-start side. I removed the other side cover and air cleaner parts, the pull-start is good but I'm sure I'll have to replace the carb, or at least the choke.

View attachment 234492

View attachment 234493

View attachment 234494

 

[rupedoggy]

I am still not convinced it isn't the chain brake but if you are sure it is not, then it is probably that pin. The saw has obviously been in the weather and the steel pin in the aluminum casting has set up an electrosis The pin is almost welded into place. PB blaster and wedging the cover and a tapping from behing might do it.

 

[hangfirew8]

It was the pin

I got the cover off today. I tried drilling into the back of the pin and using a slide hammer, but it kept tearing out. Finally I drilled the pin itself until I could tear the cover off.

It is still wedged in the casting. I am going to let it soak with Liquid Wrench for a couple of weeks before trying to get it out with vice grips. I left enough to grab. I am taking the same approach with the spark plug. With the wire and boot out of the way, I am soaking it in LW for a long time before even trying to remove it.

Now begins the process of buying parts and trying not to run the overall cost up as much as a new saw.

HF