Chain won't spin after tightening the nut

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Chain is brand new, not had even half an hour of cutting. Almost sure, it did not hit steel, but let me take some pictures by end of week and you can tell better.
 
A good way to see what is going on is to mount the bar and chain without the side cover on. Just use a couple of large nuts or some washers to make up for the thickness of the side cover, tighten the bar nuts finger tight and pull the bar forward to get the chain tension right then tighten the bar nuts to hold it in place. You can now spool the chain around the bar and see if it is rubbing on anything, if not then the problem should be with the side cover and it probably needs a guide plate to space it out farther. Do NOT overtighten bar nuts, if you strip the studs they are not fun to replace. Don't use a wrench with a longer handle then 6"
 
Hi all,
been quite a while, but did not have much time. Done as suggested, but only had four washers, so mounted them on one bolt only, but did the job. The chain was moving along the bar with a gentle pull. So, must be the cover then that is pinching it. I am wondering if I add 2 washers that are less then 1mm thick, lets say 0,5mm thick, would that be OK, or it is not recommended.
Here some pictures. If you need more, I can do some in a few days. Just let me know what you need pictures of.

20200327-123245.jpg

20200327-123249.jpg

20200327-123256.jpg

20200327-123341.jpg
 
Can't tell from the photo but is your chain so short that the tail end of the bar is rubbing against the clutch drum? You can't just add a washer between the bar and the cover plate, you need a proper guide plate that will cover the bar oiler holes or it will just puke oil everywhere except on the chain. Guide plates are easy to make and you probably don't need a very thick one.
 
The teeth next you thumb in the image above looks bent out over the side of the bar,
or is it camera angle.
 
Is that a pin sticking out of the side of the drive sprocket, should it be there.
And that bar is too close to the clutch drum for comfort.
When I enlarge the third image up, I see the bar was heatened, are you sure
its straight, are you sure it’s not delaminated and the rails push and clamp
the chain when tight.
Was there a thin washer behind the clutch drum, usually there is, is it missing.
 
I see you are from Bulgaria, welcome.

Show us a picture of the inside cover.

Try putting on the bar and cover without the chain. Flip saw over and with the chain brake off, finger or tool see if the sprocket spins freely.

What has changed since it was working properly? What and how your were using it and what happened?

Most of the time it is the last thing you did that caused the change in condition.
 
Hi,
need to check all suggestion as soon as possible, as dont have much time, but will try to do by end of week. The bar is not rubbing against the sprocket, at least it wasnt, but I recently changed the sprocket as the old one worn out. there werent any signs of the bar rubbing on it. How can a new plate be made?
#2 Whinbush, The pin sticking drives the oil pump. It is there. Also, need to check the pins, but I guess it is from camera angle. Also, how can I check if bar is straight? Butting it on a glass or something?
#3 PV Hiker, I bought of ebay end of last year, but haven't used it. Only once for no more than 15 mins. According to seller, it has been serviced recently and new chain fitted. that is all I know about it before it came to me. As stated above, I will trying taking some more pictures by end of the week. BTW that is the older model, without a chain brake. Also, I came to me with the bar off. So when I mounted it first time, that problem appeared. If someone has the same model, I will do appreciate a picture of the cover, just to compare if all there on mine.
 
That’s a Stihl bar, on what you say is a Husqvarna saw.
I never seen any cream or white paint on aHusqvarna.
I wasn’t aware a Stihl bar would work, without modification.

Check chain well to make sure no teeth are bent out of line,
and check all the drive links that slide through the bar to ensure they
are not stressed or bent, if they are they will jam up in the bar.
I never seen a saw with an oil pump out in the side casing.
Will your saw run with the chain cover on it, no bar no chain
and chain oil pumping out.

You said you added a new clutch drum, was there a washer maybe stuck
on the inside of the old one, some saws have a washer there to keep
things lined up and reduce friction from rubbing.

Is there a sprocket in the nose of your bar, is it sticking, is it the right sprocket,
a .325 for a .325 chain, or a 3/8 for a 3/8 chain.
 
I see no nice shiny marks on your saw casing, like there would be if a chain rubbed,
so am guessing if your chain has no bent or twisted drive links, that your nose
sprocket and bar are probably a miss match for your chain and drive sprocket.

This can cause jamming, but then you say this catching only happens when
you tighten the bar nuts.

Turn your saw by hand and see if the crank is bent, this will make it impossible to keep a tight chain,
as in one position the chain will be loose, then as the crank rotates it will be tight, will feel
like a catching chain if you turn the chain by hand.
 
That’s a Stihl bar, on what you say is a Husqvarna saw.
I never seen any cream or white paint on aHusqvarna.
I wasn’t aware a Stihl bar would work, without modification.

Check chain well to make sure no teeth are bent out of line,
and check all the drive links that slide through the bar to ensure they
are not stressed or bent, if they are they will jam up in the bar.
I never seen a saw with an oil pump out in the side casing.
Will your saw run with the chain cover on it, no bar no chain
and chain oil pumping out.

You said you added a new clutch drum, was there a washer maybe stuck
on the inside of the old one, some saws have a washer there to keep
things lined up and reduce friction from rubbing.

Is there a sprocket in the nose of your bar, is it sticking, is it the right sprocket,
a .325 for a .325 chain, or a 3/8 for a 3/8 chain.
Yes, this model has the oil pump housed in the cover. I did not try running with cover on and without chain and bar, but it should run without problems I guess. Yes, there is a very thin washer between clutch and drum and it is there, i did not touch this. It was there with the old sprocket as well, and I still had same issue. So i would say it is not that. Chain and drum are .404
No, there are no shiny marks, all covered with oil and debris from log cut. The bar is hard nose, no sprocket on it. I showed it to a dealer when I bought the new drum and he said all three seems to be the right ones, meaning bar, chain and sprocket are compatible.
Do I have to remove the drum to check for the crank and whether it is bent or not?
 
Yes, this model has the oil pump housed in the cover. I did not try running with cover on and without chain and bar, but it should run without problems I guess. Yes, there is a very thin washer between clutch and drum and it is there, i did not touch this. It was there with the old sprocket as well, and I still had same issue. So i would say it is not that. Chain and drum are .404
No, there are no shiny marks, all covered with oil and debris from log cut. The bar is hard nose, no sprocket on it. I showed it to a dealer when I bought the new drum and he said all three seems to be the right ones, meaning bar, chain and sprocket are compatible.
Do I have to remove the drum to check for the crank and whether it is bent or not?
No, put the bar and chain on with the washers and nut, tension it right,
make sure bar doesn’t move,
then turn the chain by hand and see if you find loose spots or spots where it gets tight,
it should spin pretty much the same as it rotates.
.404 is large, what cc is the saw, is it a Husqvarna or Stihl.
I don’t use a .404 , but would the drive links be larger and rubbing between the
rails, or on the bottom of the track they run in, they should not run on the bottom
of the track, only on the top of the rails.

You mention oil and debris from cutting, you must have cleaned it very well as
I don’t see a drop of oil, are you sure the saw is oiling.
 
That’s a Stihl bar, on what you say is a Husqvarna saw.
I never seen any cream or white paint on aHusqvarna.
I wasn’t aware a Stihl bar would work, without modification.

Check chain well to make sure no teeth are bent out of line,
and check all the drive links that slide through the bar to ensure they
are not stressed or bent, if they are they will jam up in the bar.
I never seen a saw with an oil pump out in the side casing.
Will your saw run with the chain cover on it, no bar no chain
and chain oil pumping out.

You said you added a new clutch drum, was there a washer maybe stuck
on the inside of the old one, some saws have a washer there to keep
things lined up and reduce friction from rubbing.

Is there a sprocket in the nose of your bar, is it sticking, is it the right sprocket,
a .325 for a .325 chain, or a 3/8 for a 3/8 chain.
For everyone's information - At post #150, we went from a Husky to a Stihl 08s from another member with same / similar problem.
 
No, put the bar and chain on with the washers and nut, tension it right,
make sure bar doesn’t move,
then turn the chain by hand and see if you find loose spots or spots where it gets tight,
it should spin pretty much the same as it rotates.
.404 is large, what cc is the saw, is it a Husqvarna or Stihl.
I don’t use a .404 , but would the drive links be larger and rubbing between the
rails, or on the bottom of the track they run in, they should not run on the bottom
of the track, only on the top of the rails.

You mention oil and debris from cutting, you must have cleaned it very well as
I don’t see a drop of oil, are you sure the saw is oiling.
IT is Stihl 08s. Originally comes with .404. Yes, it does oil properly, that was the first thing I tested when bought it. Links run on top of the bar, i can also do a close up photo of that as well. I will check again and report back.
 
IT is Stihl 08s. Originally comes with .404. Yes, it does oil properly, that was the first thing I tested when bought it. Links run on top of the bar, i can also do a close up photo of that as well. I will check again and report back.
Check the back end of the bar next the drive gear, make sure it’s not bent or closed in,
as the chain will hit against it as it comes off the drive and enters into the rails of the bar.
 
Everyone insists on coming up with weird faults and ignore the fact that the chain spools along the bar freely without the side cover but gets jammed up when the nuts are tightened with the side cover on. Need to do a CAREFUL check of what's going on with the side cover. Can you post pics of the side cover? I don't think I have seen one with oil pump in the side cover.
 
I'm waiting for the image... as I posted a request. See below.
.
I see you are from Bulgaria, welcome.

Show us a picture of the inside cover.

Try putting on the bar and cover without the chain. Flip saw over and with the chain brake off, finger or tool see if the sprocket spins freely.

What has changed since it was working properly? What and how your were using it and what happened?

Most of the time it is the last thing you did that caused the change in condition.
 
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