084 versus 090 versus 076

[phred45]

Took the chain and blade off again for some pictures. Need my real camera the cell pics aren't very good.
Here is the problem. When I put the chain back on the bar and drive sprocket, the chain will not let me turn it by hand and when forced it comes out of the sprocket. The brake was off, I made sure.

 

[smokinj]

Took the chain and blade off again for some pictures. Need my real camera the cell pics aren't very good.
Here is the problem. When I put the chain back on the bar and drive sprocket, the chain will not let me turn it by hand and when forced it comes out of the sprocket. The brake was off, I made sure.

Is it a hard nose?

 

[BobL]

OK the sprocket looks like it's not sitting close up enough to the drum. The problem could be that the spline/sprocket has small casting flaws/burrs on it. You need to take off the clutch drum and check the sprocket sits up against the drum. If necessary you will need to grind down the flaw on the spline or sprocket. I use a Dremel tool with a carbide burr to tidy mine up but sometimes just a piece of wet and dry folded around a piece of plastic is enough.

 

[mtngun]

Maybe it is just the picture angle, but I have to agree that the bar does not seem to be aligned with the rim.

It's not clear why the rim can't slide over (toward the bottom of the pic) to improve alignment. ? ? ?

I don't know the answer, but I posted your pic hoping that one of the 076 owners will come along and generate some ideas.

Nothing to do with alignment, but sometimes when the Carlton bar is new, it may have clear coat in the bar groove, and the chain may bind in the groove. The problem takes care of itself as soon as the chain starts spinning, but can cause the chain to refuse to move in the meantime. You can check that by seeing if the chain will slide freely in the bar while the bar is off the saw.

 

[BobL]

I Just looked at this again and may be going crazy . . . . . . but it seems like you have put the clutch drum on the wrong way around ?

Maybe I'm not used to be looking at it from this angle but you seem to have put the clutch back using the blue line orientation whereas you should be using the red?

 

[mtngun]

Is the 076 clutch an outie or an innie ?

 

[BobL]

Is the 076 clutch an outie or an innie ?

Outtie, and the bottom of those images is definitely the saw.

 

[phred45]

Outtie, and the bottom of those images is definitely the saw.

The clutch is an outie and the bar has a sprocket nose. Where mtngun shows the ?? in red is where the drive sprocket sits on top of the lugs from the oiler. Should the sprocket sit flush on the oiler? If so then I must have the wrong sprockets. It seems they did change the design at some point from pins to lugs. Mine definitely has lugs.

I'll try to get better pics but am pretty sure the clutch is in right. On the pics the top is the cover and the bottom the saw. I guess it looks kind of upside down, I tried to get enough light into it.

 

[Bedford]

I Just looked at this again and may be going crazy . . . . . . but it seems like you have put the clutch drum on the wrong way around ?

I agree, there's something strange here, those pics in post #62 are opposites. I don't think you could put the clutch on backwards as there is no recess in the housing to fit it, these have to be different saws.

 

[mtngun]

The other picture. Clutch on outside, rim on inside. I think that is called an outboard clutch ?

The rim sprocket should "float" on the splines. It should have some wiggle room to move side to side so that it self-aligns with the bar and chain. If it is not free to move side to side, then something is wrong.

Phred45, I don't know the answer, but if it were my saw, I would take the clutch off and go over everything with a fine tooth comb.

 

[phred45]

Start new thread for 076

Hi everybody,
I'm going to start a new thread with this so maybe some other 076 owners see it.
Finally got some pretty good pictures. Took everything apart again checked it for burs etc. and reassembled. Still the same problem. Everything moves freely until the chain goes on. The chain moves somewhat tight in the bar but it pulls through by hand pretty well, so that's probably just being new.
Once the chain goes over the drive sprocket it binds and won't turn.
Could the oil pump be sitting too high? Never took it out.
Also a pic of the repaired tank, not pretty but works.

 

[BobL]

Hi everybody,
I'm going to start a new thread with this so maybe some other 076 owners see it.
Finally got some pretty good pictures. Took everything apart again checked it for burs etc. and reassembled. Still the same problem. Everything moves freely until the chain goes on. The chain moves somewhat tight in the bar but it pulls through by hand pretty well, so that's probably just being new.
Once the chain goes over the drive sprocket it binds and won't turn.
Could the oil pump be sitting too high? Never took it out.
Also a pic of the repaired tank, not pretty but works.

Everything looks OK in terms of order of assembly but this picture suggests the sprocket is still not sliding smoothly on the spline and not floating into line, otherwise it would have fallen down the spline onto the case.

Also look at the phrase in bold in your quote. This suggests the drive links are peened or damaged. Post a pic of the drive links
[EDIT] OK I see from your other post the chain is new.
Then the sprocket itself might have burrs inside where the drive links sit.

Can you also retake this picture so it is easier to see what is going on?

One more thing. Try using a screwdriver to lever the sprocket over into line as shown in this picture. If it does not move you have burs to attend to.

 

[phred45]

Hi Bobl,
The sprocket moves fine when the chain is not on it. Did you see the new pics? The lugs sticking up from the oiler are holding the sprocket up too high but I don't know why. The parts are all new and Mntgn suggested that the bar may have some clear coat in the bar groove. When I hang the chain on the bar and pull it over the nose it slides, where as when it goes through the sprocket it doesn't want to move at all.
I'll get more pics tonight with the chain and bar mounted.

Thanks for the new post on milling for us newbies. Much appreciated. This whole site is awsome.

 

[super3]

The lugs on the oiler should recess into the clutch drum not the sprocket. Does the drum have notches in it for the oiler?

 

[mtngun]

Does the drum have notches in it for the oiler?

Phred45, please post a pic of the new clutch drum, and also the old clutch drum if you still have it.

 

[cgarman]

076 sprocket

I may be a little late with this, but I had the same problem, and it took forever to figure out. Hopefully I can help....

The 076 has a weird oiler that requires a special rim sprocket. I had one that looked like it fit fine, but then I noticed the chain misalignment like your photo. After lots of searching, I found a rim sprocket by Stihl specifically for the 076. It looks the same as the generic sprockets (Oregen, etc.) except that it has extra notches to fit the oiler lugs. Once it's aligned with the lugs, the rim sprocket should float back and forth on the drum by about 1/16". That is what allows everything to fall back into alignment with the bar.

I don't know the P/N, but hopefully it's helpful to know you have a problem that will cost $5 to fix and make your saw run 3x better.

 

[betterbuilt]

Eventually this was moved to another thread and the problem was solved.


http://www.arboristsite.com/milling-saw-mills/145151.htm