Export thread

Hello all,

I've got a John Deere LT160d 42" lawn mower and I'm having the WORST trouble getting a new deck belt installed. I mean... this has been rough! It's just too freakin tight!

When you guys replace your deck belt, do you disconnect the deck from the mower or do you leave it hooked up while you put the new belt on all the pulleys?

I ask because with the deck connected I could NOT get the new belt on all the pulleys- no matter which one I tried last. I tried articulating all the levers and pedals to make more room. When I disconnected the deck from the mower, I was able to slide it forward enough to hook through all the pulleys even the one coming off the engine- but then it was too tight to be able to hook the deck back up!

Please help!

You always pull the deck off.
Not that you need to do it but when you replace a belt is a good time to check blades , bearings and pulleys and 7 out of 10 times one of them is why you are replacing the belt in the first place.

If it ir really really tight either you are routing it wrong or the PTO is still engaged

Sorry Bert, but in this case the deck must be installed and yes it is very tight. Easiest way is put a socket on the nut on the movable tensioner pulley with a breaker bar attached. This will give you the leverage you need to install the belt. Are you using an OEM or aftermarket belt. Most aftermarket belts are a 1/2" shorter than OEM.

bertsmobile1 said:

You always pull the deck off.
Not that you need to do it but when you replace a belt is a good time to check blades , bearings and pulleys and 7 out of 10 times one of them is why you are replacing the belt in the first place.

If it ir really really tight either you are routing it wrong or the PTO is still engaged

Click to expand...

Ah, good point. I'll check everything out while I have the deck off- including the routing. Thanks for the info!

Rivets said:

Sorry Bert, but in this case the deck must be installed and yes it is very tight. Easiest way is put a socket on the nut on the movable tensioner pulley with a breaker bar attached. This will give you the leverage you need to install the belt. Are you using an OEM or aftermarket belt. Most aftermarket belts are a 1/2" shorter than OEM.

Click to expand...

Unfortunately i lost the packaging for the belt, and don't remember if it's OEM or not. I did measure it against an aftermarket one today and it was near as I could tell in size. Thanks for the tip about socket/breaker bar! I'm gonna try it tomorrow!

Okay, after the third afternoon of sweating, cursing, and general bewilderment on my part, I've tapped out and called a local professional to come by and assist with this green cluster in my driveway. I will watch closely to see what the heck I have been doing wrong!:confused2:

Well that was weird. The repair guy came out and couldn't get the new belt to fit. He went to Lowes and bought a new belt that he said he verified as the right size- and it wouldn't fit... way too tight. It was the same size as the one I bought. We measured it against the original and the ones we bought are like 3" shorter. Sort of at a loss. He had to leave after spending hours working on it but said he would "try and make it back later this week". Doesn't sound too promising lol.

Anyone ever heard of belts supposedly being the right size- but in actuality being too short like this?

Lost in translation lol. I've seen it happen before.Its very likely the supplier changed belt manufacture or the numbers cross referenced wrong.Hope he's not charging you by the hour for half a day trying to install the wrong belt.

happens all the time to me.
Most of the stuff I work on is 10 yo or older so lots of stuff gets changed and lots of stuff is different on the models we get down here.
Chasing up an idler pulley for a Murray 42" deck, fitted to a Stihl Viking.
Pulley should be #690387 3.5" x 1" but the correct pulley is 4" x 1.45"

Thanks for the feedback guys! I realized the 42" John Deere LT160 will not necessarily accept whatever 42" John Deere belt the big box store has for sale and says will fit. Ordered the correct belt M126536. Now if this doesn't work I'm going to use this mower for .308 target practice LOL.