After you install bar,chain,and brake cover(tightened)the chain wont turn.

take it to a Husky dealer and they will fix what is wrong with it

take it to a Husky dealer and they will fix it for you

It can be a little tricky!

If you are referring to chain break band

Tools you will need:
1/2 Socket (to remove bar nuts)
T25(torq) or you can use a Flathead screw driver but is a little harder.

Remove 2 bar nuts,Clutch cover,bar,chain, 2 screws on black bar handle right behind clutch cover(this is needed because there is a hidden screw there for the chain break) You will need a new chain brake (my guess is that it is part # 530071893 aprox $15) but you will want to verify that with your model number.

You should see the chain break assembly, 3 - T25 screws are visible after the clutch cover is removed(note sometimes you have to clean saw dust to make screw head visible) the other T25 screw is hidden under the black bar handle. Once you remove all 4 screws on the chain brake you will be able to pull it off.

Installing the new one is the tricky part because if it is set(or break is on) you will have a hard time putting it on.One of the easiest ways is to focus on it near the muffler you will see that a metal 3 pronged gear fits into the plastic part of the chain break handle.and if the band is too tight to fit over the clutch drum you will have to carefully reset it by applying pressure onto the area that has the 3 pronged gear and chain break handle make sure that the handle is pushed forward all the way while you apply pressure then slowly pull chain break handle back till you hear a "snap" this resets the chain brake spring and the band should now fit over the clutch drum.Now, proceed with putting back together 4 chain brake assembly screws,2 handle screws,and bar,chain,clutch cover,and 2 bar nuts.

Please note it is important that you apply quite a bit of pressure onto chain break area where metal (3 pronged) gear fits into handle while resetting or when you reset it the metal part can cut into and damage the plastic piece in the chain break handle.

You can see a breakdown here: http://www.searspartsdirect.com/partsdirect/part-model/Poulan-Parts/Chainsaw-Parts/Model-P4018WT/1324/1503220/P0506041/00002?blt=06&prst=0&shdMod=P4018WT

Hope this helps!

Set the chain brake to off, then remove the fasteners on the right side cover where the chain drives from. This will release the bar which will slide back toward the engine and allow the chain to be removed. Note the direction of the cutting edge of the teeth. Clean everything including the two small oil passages that run from the large holes in the bar out to the chain groove on each edge of the bar. When refitting a new chain, back off on the chain adjustment screw (CCW) a few turns to allow the cover to fit to the bar properly. Fit the chain over the clutch sprocket, then insert the bar to the engine. Work the chain over the bar, then pull the bar outward to tighten the chain. Install the cover and the fasteners finger tight. Make sure the cover fits the bar properly. Tighten the chain adjuster CW so that the chain pulls up to the lower bar edge, but not so tight that you can't turn the chain by hand. Tighten the cover fasteners, then recheck the chain tension. The lower run of chain should be cutting as the chain moves toward the engine. Check the chain oiling by running the saw at speed with the bar tip near some cardboard--it should throw off a thin line of oil after several moments. Hope this helps!

Got to homelite.com and input your model number.
WARNING:
When servicing, use only identical Homelite
replacement parts. Use of any other parts may
create a hazard or cause product damage.
WARNING:
Always wear safety goggles or safety glasses
with side shields during power tool operation or
when blowing dust. If operation is dusty, also
wear a dust mask.
GENERAL MAINTENANCE
Avoid using solvents when cleaning plastic parts.
Most plastics are susceptible to damage from
various types of commercial solvents and may be
damaged by their use. Use clean cloths to remove
dirt, dust, lubricant, grease, etc.
WARNING:
Do not at any time let brake fluids, gasoline,
petroleum-based products, penetrating
oils, etc., come in contact with
plastic parts. Chemicals can damage, weaken or
destroy plastic which may result in serious
personal injury.
LUBRICATION
All of the bearings in this product are lubricated with
a sufficient amount of high grade lubricant for the
life of the unit under normal operating conditions.
Therefore, no further lubrication is required.
REPLACING THE guide BAR AND
CHAIN
See Figures 34 - 43.
DANGER:
Never start the engine before installing the
guide bar, chain, clutch cover, and clutch drum.
Without all these parts in place, the clutch can
fly off or explode, exposing the user to possible
serious injury.
maintenance
Fig. 34
Fig. 35
Fig. 36
WARNING:
To avoid serious personal injury, read and
understand all the safety instructions in this
section.
n Always place the switch in the stop “ ” position
before you work on the saw.
clutch
cover
Run
Position
sprocket
Page 26 — English
cutters
bar
groove
chain drive links
Fig. 38
maintenance
chain rotation
chain drive links
Fig. 37
n Make sure the chain brake is not set by pulling
the chain brake lever/hand guard towards the
front handle to the run position.
NOTE: When replacing the guide bar and chain,
always use the specified bar and chain listed in
the Bar and Chain Combinations section later
in this manual.
n Wear gloves when handling the chain and bar.
These components are sharp and may contain
burrs.
n Press in on the clutch cover lock knob and rotate
counterclockwise until the clutch cover can be
removed.
n Remove the bar and chain from the mounting
surface.
n Remove the old chain from the bar.
n Lay out the new saw chain in a loop and
straighten any kinks. The cutters should face
in the direction of chain rotation. If they face
backwards, turn the loop over.
n Place the chain drive links into the bar groove
as shown.
n Position the chain so there is a loop at the back
of the bar.
n Hold the chain in position on the bar and place
the loop around the sprocket.
n Fit the bar flush against the mounting surface
so that the bar studs are in the long slot of the
bar.
n Replace the clutch cover ensuring that the
adjusting pin in the clutch cover is in the bar
chain tensioning pin hole and that both bar
studs are securely in their respective holes in
the clutch cover.
NOTE: The adjusting pin may need to be slightly
repositioned with the chain tensioning dial so
that it is aligned with the position of the bar chain
tensioning pin hole.
n Replace the clutch cover and rotate clutch
cover lock knob just enough to hold the cover
in position.
NOTE: The bar must be free to move for chain
tension adjustment.
n Lift the tip of the guide bar up to check for sag.
n Remove all slack from the chain by rotating the
chain tensioning dial clockwise until the chain
seats snugly against the bar with the drive links
in the bar groove.
n Release the tip of the guide bar and, if the chain
sags, turn the chain tensioning dial clockwise.
Repeat this process until sag does not exist.
n Hold the tip of the guide bar up and tighten the
clutch cover lock knob securely.

I am assuming your saw has an outboard clutch (most Macs do).
Please see page 16 here:
http://weborder.husqvarna.com/order_static/doc/HOUS/HOUS2005/HOUS2005_1140247-95.pdf
It is possible to install it backward look colsely at the orientation in the second illustration from the bottom, left column.
New chains stretch Please for your safety watch it and tighten when needed.
Chain Adjustment

1. Make sure the chain brake is off (gloves will protest your fingers).
2. If necessary, loosen the bar nuts that are clamping the clutch cover in place (or whatever holds the clutch cover and bar on). They do not need these really loose - finger tight will do.
3. Ease the tension adjustment until the chain is obviously loose.
4. Using one hand, hold the nose of the bar up.
5. While holding the nose up, adjust the tensioner so that the center of the chain just touches the underside of the bar, add a touch more.
6. Continue holding the nose of the bar up & tighten up the bar nuts / bolts / quick-release system. HTH

Lou

If you are having difficulty fitting the drive links into the bar groove, the chain binds or rides up when rotated there may be burrs on the drive links. These often form if the chain comes off while at speed. use a file on the drive link flats to remove them.


Chain Adjustment

1. Make sure the chain brake is off (gloves will protest your fingers).
2. If necessary, loosen the bar nuts that are clamping the clutch cover in place (or whatever holds the clutch cover and bar on). They do not need these really loose - finger tight will do.
3. Ease the tension adjustment until the chain is obviously loose.
4. Using one hand, hold the nose of the bar up.
5. While holding the nose up, adjust the tensioner so that the center of the chain just touches the underside of the bar, add a touch more.
6. Continue holding the nose of the bar up & tighten up the bar nuts / bolts / quick-release system. HTH

Lou

Look closely at your chain, I'll wager it is the opposite direction.
Chain adjustment

1. Make sure the chain brake is off (gloves will protest your fingers).
2. If necessary, loosen the bar nuts that are clamping the clutch cover in place (or whatever holds the clutch cover and bar on). They don't need these really loose - finger tight will do.
3. Ease the tension adjustment until the chain is obviously loose.
4. Using one hand, hold the nose of the bar up.
5. While holding the nose up, adjust the tensioner so that the center of the chain just touches the underside of the bar, add a touch more.
6. Continue holding the nose of the bar up & tighten up the bar nuts / bolts / quick-release system. HTH

Lou

Wearing gloves is recommended. Loosen the bar slide it againt the clutch. Place the new chain over the clutch like pictured below. Place the drive links in the groove and work tour way right until the chain is over the bar nose. Grasp the nose and pull it right, the chain should rise toward the bar bottom. If necessary guide the drive into the bar groove. Find the chain tensioner and adjust it to fit the bar. Proceed as below.
Chain adjustment

1. Make sure the chain brake is off (gloves will protest your fingers).
2. If necessary, loosen the bar nuts that are clamping the clutch cover in place (or whatever holds the clutch cover and bar on). They don't need these really loose - finger tight will do.
3. Ease the tension adjustment until the chain is obviously loose.
4. Using one hand, hold the nose of the bar up.
5. While holding the nose up, adjust the tensioner so that the center of the chain just touches the underside of the bar, add a touch more.
6. Continue holding the nose of the bar up & tighten up the bar nuts / bolts / quick-release system.

Did the cover crack? The adjusting screw is just a common metric screw; the nut has a special tang that engages one of the 2 large holes at the drive end of the bar. When reinstalling the bar and chain, the adjustment screw must be backed off a few turns so the the tang will readily drop into it's hole in the bar. Install the cover (new if old one cracked) and turn the nut(s) down finger tight. Turn the adjuster CW to tighten the chain so that the chain doesn't droop from the bar, but turns freely by hand. Tighten the cover nut(s) and recheck the chain again.