I have a Husqvarna LR121 and need to replace the cutting deck belt but I have lost the manual that shows how the belt goes around the pulleys and if I actually have to remove the deck to fit the belt. Mal

Any debris on top of the deck e.g. thumb sized mulch, driveway stones, pencil diameter sticks or larger. All may cut and snap a belt if they get wedged between the belt and any of the pulleys.

Any hard foreign object of the size that will jamb into a pulley v groove.

If the belt has come off a few times then it has probably stretched and now is shot and needs replacing, you may need to cut it to get it off from under the pulley, there is normally a keeper around the back of the pulley to stop this happening, it may need to be adjusted closer to the pulley to stop this happening again, the operators manual should show the correct routing of the belt.

Looking underneath the mower on top of the deck there should be a flat metal arm with a flat faced pulley on the end. This pulley pushes against the belt that drives the mower deck . The spring should be hooked on that arm and pulled tight over to a place on the deck and this is what keeps the belt tight enough to turn the blades when you engage the pto switch. My recommendations to put this back on is to remove the belt pulley cover on the deck right side roll the belt off at that pulley giving you a bunch of slack so you can hook up the spring and put the belt in the right position on everything else then go back to the deck right hand pulley start putting the belt back on that pulley and when it is to tight to get it all the way on reach under the deck and use the blade as leverage to finish turning the pulley and walk that belt on the rest of the way ,it will not hurt a thing, all you are doing is pulling that 7 inch spring over like it was intended to be, then replace the cover on the deck spindle.

the bearings in one of the blade houseing r going out

Parts and Diagrams for Husqvarna LT 18542 954571748 2003 11
OH BOY, lots of information. one belt runs the DRIVE LINE. one belt will run the CUTTING DECK. check out the link.Hope this helps :)

Your deck should have a couple "idler" pulleys on them in addition to the main mandrell pulleys that have tension on them via springs to keep tension on your deck belt. Maybe you need to really examine the condition of those "idler" pulleys and also the main pulleys to find the problem.

i had a 2148. you remove the mower deck as the first step. feed the belt over the pulley on top the transmission, then put it over the engine pulley. then have someone push the clutch pedal in so the tensioner pulley moves, put the belt in the guide pulley and on the tensioner. release the clutch put the deck back on and you are good to go. notice there are little keepers welded to the frame for the front, engine, pulley and it is easy to mistakenly put the belt over them instead of under them.

a general rule is that a pulley shaped like a Vee takes the V of the belt whilst a pulley which is flat takes the flat back of the belt. if you bear that in mind you will not have a problem putting belts back on. also there is a little decal on top the deck showing how the deck belt and deck drive belt go.

The manual shows how the belts are put on, if you do not have one they may be purchased through dealers or small engine repair shops or online. On mine there is also a little diagram on the top of the mower deck. Another way to check is find an identical one that is functional and look at its belt. There are only so many ways it could fit and these are all made by just one or two manufacturers so there is not much variance.

The deck drive belt makes an L shape looping to the the outside deck pulley that has 2 pulleys. The deck drive belt rides on the top set. X = pulley engine x
l l
l l
l l -
l l x x = outside deck pulley
back deck pulley =x
motor to idle to outside
motor to tension to outside back side of belt goes around idler
This is the most common belt to replace
idle pulley (x)
lx tension pulley
/ l_______
the deck running belt left deck (X ________________ ____ x)

The deck drive belt makes an L shape looping to the the outside deck pulley that has 2 pulleys. The deck drive belt rides on the top set. X = pulley engine x
l l
l l
l l -
l l x x = outside deck pulley
back deck pulley =x
motor to idle to outside
motor to tension to outside back side of belt goes around idler