How to Change the Traction Belt on a John Deere LT155

113,435

16

16

Introduction: How to Change the Traction Belt on a John Deere LT155

The traction belt is the one that delivers engine power to the transmission. Start by removing the deck and raising the tractor up so you can work underneath safely. Deck removal is covered in the operators manual, which you can view for free on John Deere's website in case you don't have one of your own. (The operators manual doesn't cover replacing the traction belt.)

Step 1: It Isn't As Bad As It Looks.

The belt rides up above the steering mechanism and the crossbars for the brake and deck lift. At first glance it looks like you're going to need to remove all these things, but you don't have to. The only thing you'll need to do to get the belt clear of these components is disconnect the steering tie rods.

Step 2: Remove the Tension Spring.

The tension spring is hooked around a bushing on the idler and a notch on the tension arm. Remove the spring to release tension on the belt. You'll want the brake in the released position for this step. Once the spring is off and the tension is released, you'll be able to pull the belt off the transmission sheave and pull some slack up toward the front of the mower, which you'll need in the next step.

Step 3: Disconnect the Tie Rods and Remove the Belt From the Motor.

I disconnected mine at the front because the cotter pins are easier to get to up there. It would probably be a lot easier to see what you're doing if you disconnect them from the bellcrank on the steering sector. Either way, pull the loop off the motor pulley and drop it below the steering sector.

Step 4: Remove the Idler.

The belt is trapped between this little idler and the frame on the left side of the mower so you'll need to remove it. Use a 13mm socket to loosen the nut and try not to lose the bushing that the spring hooks to. You can get to the head of the bolt to pull it up and out by reaching through the opening where the steering sector gear is located.

Step 5: Remove the Belt From the Tensioner Assembly.

Use your 13mm socket to remove the tensioner idler sheave then remove the guide from the tensioner pulley to free the belt from the tensioner assembly. After you do this, the belt can be removed by threading it out from on top of the brake and lift shafts. There's a pawl lever sticking up on the deck lift shaft that you'll need to work the belt over top of to get the belt all on the same side. You can see a good view of the pawl in the picture of the idler in step 2. Pull the rear loop forward over the two shafts until the entire belt is clear of the mower.

Step 6: Put the New Belt on the Same Way the Old One Came Off.

Thread the new belt over top of the two shafts and work the left side of it over the pawl on the lift shaft. Put the idler back on next to the left side of the frame.

Step 7: Put the Tensioner Back Together.

Thread the belt around the tension pulley and put the guide back on, then thread it around the tension idler and finish reassembling the tensioner assembly. The tension pulley is bolted through a slot in the tension arm, and I think this is so you can fine tune the belt tension by moving the pulley back and forth along the slot. I left mine where it originally was and it worked fine.

Step 8: Put the Tension Spring Back on and Finish Up.

Thread the belt over the engine pulley at the front and the transmission pulley at the back, then put the tension spring back on to tension the belt. Make sure the new belt is routed properly, reattach the steering tie rods, and you're ready to put the deck back on and put the mower back into service.

Be the First to Share

    Recommendations

    • Make it Real Student Design Challenge #3

      Make it Real Student Design Challenge #3
    • Toys & Games Contest

      Toys & Games Contest
    • Barbecue Speed Challenge

      Barbecue Speed Challenge

    16 Comments

    0
    glenshifflett54
    glenshifflett54

    Question 19 hours ago on Step 6

    What size drive belt does a John deer lt 150 does it take

    0
    NC_Don
    NC_Don

    7 days ago

    Fantastic Instructions! I got my 20 year old LT155 rolling again without spending $$$. I have two tips: 1. Yes, it is difficult to handle the springs. I took a nylon strap about 3 Feet long and placed it over the hook of the springs. I gripped the strap ends with both hands and could unhook the springs with ease. I could put the springs back in place after installing the new belt in the same way. The hooks pinched the strap but I could pull it off using a vice grip. 2. Check the mounting bolts for the engine while you are doing this job. My mower has a Koehler CV15S engine. All 4 bolts had dropped out and the engine was sitting lose on the frame. This caused the drive belt to stop working. It is easy to tighten or replace the bolts when you are replacing the drive belt. If some are missing, they were 8mm x 25 mm, JD part number 19M7867. I will check them every year now. Happy Mowing!!

    0
    AnOldNerd
    AnOldNerd

    7 weeks ago on Introduction

    Nice photos and procedure for changing the traction drive belt. I used it on my LT166. Here are suggestions to make it even better. Perhaps some text labels on the photos to correspond to your excellent labelled diagram in Step 1 as I had to go back and forth quite a bit and the original John Deere diagram that I got from my dealer was UNLABELLED! The dealer even told me the drive belt procedure and even mower deck belt routing is only in the expensive $$$ dealer service manual. Some tension springs are more worn out than others; people often re-adjust the tensioner to compensate for older drive belt stretch. This can make the big bad spring very difficult to safely remove and reinstall. Mine was really strong and too difficult to reconnect safely in the original tensioner pulley position. My big suggestion is at the tensioner pulley re-install step, it may help to (1) mark the current position with a paint pen, (2) adjust the tensioner pulley all the way to the slack position, leave the guide off until the 'big bad' tensioner spring is installed, then make sure to set tension to keep the new belt running properly. Then reinstall the tensioner guide. That procedure is often necessary on car engine belts. Again, well done sir, and thank you. Even my John Deere dealer found your procedure online in a web search.

    0
    ttp444
    ttp444

    1 year ago

    Terrific tutorial! It worked perfectly for my LT166, as well. Thank you for really helping me out.

    Re the spring tension problem, I hooked a load tie down strap onto the end of the spring and ran the other end out above the left rear wheel and hooked the other end onto my truck. Then the ratchet tightened the spring easily until it was in the right place. I push the spring up, then released the ratchet, and it snapped in place perfectly.

    0
    JeaneeV
    JeaneeV

    2 years ago on Step 2

    I think you left one step out, and that is the heavy spring for the deck lift handle.
    Very hard to remove and replace.
    Al

    0
    Blcantu2319
    Blcantu2319

    Question 2 years ago

    I had to replace the transmission belt but I’m having trouble getting the belt over and around the pawl, any advice?

    0
    JimB384
    JimB384

    Question 2 years ago on Step 8

    How do you get the tension spring back on??? Even when you release brake lock there's still quite a stretch!

    0
    Michael Law
    Michael Law

    Question 3 years ago on Step 8

    I did this procedure on aLT 180. Also replaced the idler with tension spring. Now the belt keeps slipping off. How do I adjust?

    0
    Duckman_wi
    Duckman_wi

    Answer 3 years ago

    I think the 180 is the same as the 155/160, there is no adjustment. The tension spring, or as they call it "Extension Spring" is what keeps the M144044 belt in tension. If your's looks like the one outlined here you must have something else that is wrong. There are 2 springs on the idler bracket, the M126636 is the one you had to remove and the M141502 brake lever spring. Check you idler bracket for out of round holes. All the metal on these are a soft metal and they wear out. I had to weld a couple of brackets all over my LT155 and drill them out. I'll bet if you pull the idler bracket out you will find the hole is no longer round, same for the bolt or bushing, they wear and then you have slop that causes the belts to jump. I even had to replace the rod that engages my deck, it wore down to only 1/8".

    0
    Michael Law
    Michael Law

    3 years ago on Step 8

    Help. I have to be close. Just need someone's gracious knowledge for adjustments. I'm a disabled Navy Veteran who needs a little help. Thank you.

    0
    MorrisStarkey
    MorrisStarkey

    Question 3 years ago

    Is this essentially the same for an LT133 JD? Thanks.

    Morris~

    0
    suave2
    suave2

    4 years ago

    replaced belt on LT155 john deer tractor, followed all steeps... but, gears won't engage... what can I do?

    0
    gadget-man
    gadget-man

    5 years ago

    just what I was looking for. Thanks

    0
    mrb12549.
    mrb12549.

    5 years ago

    Thanks much for the details. The dealer should be so helpful when you spend a small fortune for the belts. But they are not. This really made the job much more understandable.

    0
    tomatoskins
    tomatoskins

    5 years ago on Introduction

    This is great! I love the detail and clear pictures! Keep up the great work and welcome to the community!