Echo cs3450 tension screw won't tighten chain. I think the nut which has a tip that goes through a hole in the bar may be broken off because it doesn't seem to be enough through the hole to move the bar to tighten the chain. How much should the tip be through the hole in the bar?

Under the protective cover of the bar and chain on the motor are the nuts / bolts and chain tension adjustment screws.

Depending on model (you didn't include yours so generic instructions follow); removing the nuts / bolts that hold the cover in place will allow the bar and chain to be removed - or to adjust the chain tension on the bar with a long screw for that purpose. Once the tension is set with the adjustment screw it is locked into place when the cover is re-secured with the nuts / bolts.

If you need more specific help - please provide your make and model chainsaw.

Loosen and remove bar lock nuts and cover. screw tensioning screw to loosest point. wrap chain onto teeth of drive sprocket, then within grooves on bar. Be certain cutting edges are facing forward. Look at chain before removing. set bar with new chain to ensure the tension pin aligns with bar tensioning hole. Replace cover set nuts loosely. Tighten chain to about 1/4" out of groove when pulled on (wear gloves). Tighten nuts, spin chain to see it moves freely but does not hang free og bar groove. re-tension as necessary. Happy cutting!

Chain replacement is basically the same on all chainsaws. Loosen the side retaining nuts on the cover over the chain. Now loosen the chain tension screw ( usually a flat headed screw) at least 4 full turns. Put the saw on its side with the blade up. Remove those side cover nuts and the side cover - the blade should sag as you remove the nuts. push the blade towards the engine, paying attention to the direction of the teeth on the chain. remove the chain and clean out the junk from behind the chain around the sprocket and from the inside of the side cover. The emergency brake band is located inside the cover - make sure you clean out the debris from around the band, tensioner screw assembly, and cover. Re-install the new chain, orienting the teeth in the correct direction. Re-install the side cover, making sure the tensioner pin goes into the hole in the bar ( blade). Slightly tighten the side nuts, then re-tension the chain until you can just pull the teeth off the bar. tighten the nuts, being sure you don't over tighten them ( a little past snug is good). Run the saw for a few minutes ( doing 1 cut will speed this step along). Loosen the side cover nuts and re-tension the chain, the re-tighten the nuts.
Hope this helps!!

Turn the saw off. Look for several nuts on the right side of the saw that hold the cover on and the blade to the saw. Loosen these nuts, and before taking the cover off, loosen the chain adjuster by turning it (usually a screw head on the same side, or on the front of the saw as you look down the blade towards the saw.) Loosening the chain adjuster moves a pin that goes into the bar (the part the chain rides around when operating) to push it away from the saw to tighten the chain when you are tightening it. Take the cover off, and put the chain around the sprocket at the back like a bicycle chain, and then while holding the bar (sometimes a partner helps) parallel to the saw and outward away from the front of the saw, align the bottom parts of the chain inside the bar guide slot all around the bar, holding just enough tension that it doesn't fall off the sprocket or get misaligned in the bar guide. Try moving the chain a little bit to make sure it is not binding on anything. If it doesn't move at all, make sure the chain brake is not on. Once it is moving smoothly, put the cover back on, and begin to hand tighten the nuts. Just before they begin to get tight, eyeball where the chain tensioner pin is in relation to the hole it is supposed to go in. Adjust the chain tensioner screw to move the pin towards the hole. When it pops in the hole, continue tightening the nuts by hand until tight. Now you and your partner can let go of the bar. Adjust the chain tensioner for the proper tension in the chain, not too loose, not to tight, refere to your manual. Finish tightening the cover nuts using the universal wrench to the specifications given in the owners manual.

Look at the side of your saw where the chain and bar are; you'll see 2 nuts. These nuts will need to be loosened but don't remove just yet. Now look on that same side in front of where those nuts are and you should see a small screw head for a flat blade screwdriver.If it's not there then look on the inside of the bar on the saw body.Loosen that screw 3 turns or so then remove those nuts the rest of the way. Take of the side cover and push the bar towards the saw body - this should make the chain hang off the bar. Remove the chain and pay attention to the direction of the cutting tooth in relation to the lug in front of the tooth. This lug is the anti - kickback lug and on the new chain the lug MUST be in front of the cutting tooth of the chain. Re - install the chain, putting the back of the chain over the drum on the saw first then the front, making sure it is not hung up on the little metal bar on the bottom of the saw. Look on the bar - you'll see a hole in the bar that the peg attached to the screw goes in. Make sure that peg goes into the hole - adjust the peg by turning the screw so the peg lines up properly.Now replace the side cover, holding it flat against the saw body as you re - install those nuts on the saw. Tighten the nuts until they push the side cover flush to the saw. Now lift up on the tip of the bar and turn that screw to tighten the chain and adjust until the chain is flush all along the bar.Don't overtighten the chain as you may fry the bearings.The chain is tight enough when you lift on the chain and you can lift the link you're holding out of the track on the bar, with the bottom of the chain just barely coming out of that track.Tighten the nuts the rest of the way, being careful not to tighten them more than they were in the first place. Now start your saw per standard procedure, warm it up and make 2 cuts. Shut it off and check the chain tension to above specs - and you should be good.

There's two 1/2 inch nuts on the side of the cover from which the bar protrudes.
Remove these nuts and the cover -- leave the bar loosely in place.
Look for a slot-head chain-tensioning screw (may be on front under the bar, or perhaps on the side).
Turn this tensioning screw counter clockwise -- you will notice a pin moving back towards the drive clutch -- this pin fits into a hole on the bar and is used to set the chain tension by pushing the bar away from the drive clutch.
Once it is loosened, the bar can be pulled closer to the drive clutch, allowing you to fit the chain back onto the bar -- be careful to align the drive teeth on the chain into the slots on the drive clutch.
When the chain is back in place, turn the tensioning screw clockwise to tighten the chain onto the bar.
Replace the cover and put the nuts back on only finger-tight.
Tighten the chain some more using the tensioning screw.
Tighten the 1/2 inch nuts fully.
Note: The chain needs to be quite tight -- lift it by a link and be sure it does not come out all the way from the bar.

The nut may be cracked, like mine is. While I am trying to get a new one, I found I can still tighten the blade by laying the saw with the blade securing nuts up. Loosen the two nuts 1/2 turn. There is a small hole in the bar right near the case. Use a small screw driver placed in the hole and pry against the case to force the bar out and tighten the chain. While prying out on the bar, tighten the two nuts.

Set out the chainsaw parts in front of you. Make sure the chain is facing the right way to cut wood; the teeth should be facing away from you when you are holding the chainsaw.

Secure the chain around the sprocket (a cog-type part found near the chain tension nipple) and align it along the grooves of the bar. You will see a hole for the chain-tension nipple on the end of the bar. Line these up so the nipple fits in the hole on the bar. Pull the chain to tighten it, using the screw to achieve the desired tension

Place the cover plate back on top of the bar and line up the cover-plate housing screws with their corresponding screw holes

Screw the cover-plate housing screws back in and tighten. Test the chain to make sure it spins freely when pulled.

Check the chain to make sure you can lift it about 1/4 inch, so it isn't too tight to spin while cutting wood

Hi Eric,

You will need a ratchet and the socket that fits the nuts holding the bar on. Also a screwdriver that matches the bar tensioning screw.

The tensioning screw runs along the same plane as the bar and is located on the inboard side of the bar.

• Get the chain as close as you can to being on
• Loosen the bar nuts
• Slide the bar in until you get the chain in place
• Slide the bar out again
• Make sure the clip attached to the tensioning screw registers with the hole in the bar.
• Finger tighten the nuts
• Use the screwdriver on the tensioning screw to tighten the chain
• Ratchet the bar nuts down
  

Oil it up, it's ready to go.

Mike

Depending to what model you have, the Sprocket cover tab (located on the round part of the sprocket cover) isn’t inserted into the saw body tab slot. Or your cahin is not tensioned properly. According to the manufacturer... "The adjusting block on the adjusting screw isn’t inserted into the adjusting hole on the guide bar. Reinstall and align the sprocket cover by first removing the sprocket cover from the saw. Turn tensioning screw on the sprocket cover counter-clockwise until it stops. Pull guide bar away from saw body to remove slack from chain. Insert sprocket cover tab into saw body tab slot and lower sprocket cover into guide bar bolt. Finger tighten guide bar nut onto guide bar bolt. Slowly push guide bar toward saw body until adjusting block on the adjusting screw drops into round adjusting hole on the guide bar. Securely tighten guide bar nut after properly tensioning saw chain." If these tips do not work, you may need a new chain. You can order an new chain on-line at www.masterparts.net. I hope this helps you!