345 Drive Belt Replacement

[MarkCoburn]

Well, I started my drive belt replacement today. Here is the taking it out part.

I wanted a little extra room under the tractor so I put it on ramps and jack stands.





I'm going to take the body off like others have recommended. Since I am working alone, I'll take the two additional bolts out so I can take it off in two parts.







The Level Stop Knob can just be pulled off.



With the bolts off, I could slide the fender section back.



Since I forgot to unplug the seat sensor, I sat the rear section down like this.



With the rear section placed like that, I was able to reach through the gas tank fill hole to feed the seat sensor wire down.



While I was taking the bolts off under the foot rests, I realized that the black foot mats where held on by simple clips; so I removed them also.

I should have budgeted more time for cleaning.







Tank just sets aside.



Fan comes out with a 19mm socket or wrench, in case your wondering.



So, I just have to release enough belt tension to get it off the transaxle's pulley.



This is the spring that does the detents on your cut height selector knob. If your knob just spins freely with the mower deck raised, this is the little guy that needs replaced. I moved it out of the way because I wanted to pry where the yellow arrow is to loosen the belt.



That worked, belt is loose.



I needed the PTO's control cable disconnected.



I'll also need the spring disconnected, so I tried the ratchet strap method.





I purchased the three idler pulleys to replace with my drive belt.







I took out the 3 idlers.



With the three pulleys out, I weaved my new belt in along side the old one. The plan was to start with the front pulleys and work my way back to the transaxle. That is when I ran into my first real snag. The two smaller pulleys are not the same as the ones I took out.







The larger one is the same and that is good because it is the only one that actually feels bad. Clicking the photo below will link you to a video where I describe the condition of the three pulley's bearings.



I got the new belt around the main pulley above the PTO and the first idler pulley; then I called it a night. I'm off tomorrow and hope to get a chance to finish up.

 

[Retired Iron Peddler]

WOW! That's a lot of work! When the JD tech replaced the drive belt on my JD 345, after a belt guide broke off and "rode" the belt through a pulley and broke it, he had the belt replaced in less than an hour. He used a piece of wire to pull the belt tension spring towards the front of the tractor and tied it securely to the front frame. He removed the PTO clutch, which came off easily, and installed the new belt, reinstalled the PTO clutch, and released the wire holding the belt tension spring. He did this on my concrete driveway from under the tractor with out putting it on a jack. He was a good tech and had evidently done this before. :thumbsup:

Bill

 

[sklunk]

Mark,

I really appreciate you documenting this with all your pictures, but there is an easier way. First you have to take off tension like RetiredIronPeddler said, then this next part is what many people miss:

1) Pull the lever on the rear of the tractor (the one to manual move the tractor). This puts the transmission in neutral and will allow the plastic cooling fan to be spun by hand.
2) Remove the idler pulley nearest to the PTO and remove it from it's mounting bracket to get the belt out.
3) Remove the belt from the pulleys and carefully route the belt up between the fan blades. If you work carefully and slowly you can rotate the fan and work the belt out. Then install the new belt the same way, by routing it over a fan blade and spinning the fan by hand, slowly working the belt down onto the pulley.

Obviously you must do this SLOWLY AND CAREFULLY or you will break the fan blades, and you get kind of twisted trying to get your arm up to reach the fan, but it does work. Sorry I don't have any pictures but when I replaced mine a few years ago this process worked perfectly and I didn't have to remove the fenders. Of course I didn't change any pulleys, so having the fenders off probably helped you with those.

P.S. --
What is the grounding wire shown in this picture?

http://coburnphoto.smugmug.com/Cate...ement/i-NXrTz7d/0/XL/img20120521201134-XL.jpg

I've never seen that wire on any 345's ...

 

[Retired Iron Peddler]

Yep, I had already pulled the transmission release lever since the belt broke while I was in the yard mowing. I pulled the lever in order to roll the tractor out of the yard and on the driveway in front of my shop.

I forgot to mention that I furnished the air compressor, hose, and air impact wrench in order to remove the bolt from the engine crankshaft.

I don't mind paying for work like this when it's done by someone who is experienced and can do the job properly and much quicker than I. I don't remember what the charge was for the service call, but at the time I thought it was well worth it. I did all my wrenching for years, but as I get older with dimming vision and thinning skin on my hands, it is becoming much less fun.

Bill

 

[MarkCoburn]

There is a serial number break on the belt and pulleys. The later 345's (like yours) have the double-v belt with the wider idlers.

How many hours are on your 345? That double-v belt should have lasted a super long time, unless it got a stick in it or something.

Here are some photos of the old belt. The first one shows the missing chunk that made it obvious that I needed a new one.

 

[MarkCoburn]

WOW! That's a lot of work! When the JD tech replaced the drive belt on my JD 345, after a belt guide broke off and "rode" the belt through a pulley and broke it, he had the belt replaced in less than an hour. He used a piece of wire to pull the belt tension spring towards the front of the tractor and tied it securely to the front frame. He removed the PTO clutch, which came off easily, and installed the new belt, reinstalled the PTO clutch, and released the wire holding the belt tension spring. He did this on my concrete driveway from under the tractor with out putting it on a jack. He was a good tech and had evidently done this before. :thumbsup:

Bill

A couple weeks ago, while replacing my PTO, I slacked the drive belt and took off the front idler. It looked to me, like weaving the belt around and onto the transaxle would be a major pain, for someone like me, who had never seen what it looks like under there. I read, in some other threads, that it was worthwhile taking off the fenders. I decided to try that and clean while I was in there.

I might be a moron, but I couldn't figure out how to get the belt off and on without removing the spring. I think I read a previous post of yours, describing the wire to the front bumper. That is what I set out to do during the PTO replacement. I'm sure I'm going to feel silly when someone explains what simple thing I missed, but I don't see how he could have just pulled the spring forward and leave it there until finished. For one thing, pulling it forward actually makes the belt tension tighter.

In short, I'm glad I did it this way. Several times, I took the advantage of being able to work from above. The 5 minutes it takes to remove the fenders and fan are well worth not having to weave the belt around it. I think I would have been able to get it from below if removing the fenders was not this simple, but I would have needed to use a bunch of swear words in the process.

I've got the new belt on now. Even with the fan, spring, and the front idler removed, the belt was very snug going over the transaxle pulley. Now that I know what it looks like up there, I'd still do it this way next time.

I try to work on our things myself, if I can. It is an additional way that I provide for my family. We can buy used equipment that saves us money and maintain what we have that also saves us money. I'd have to get a second job if we paid to have someone else maintain even what little stuff we have. It can be frustrating and rigorous working on our car, truck, tractor, etc. I try to take my time and make it as easy as possible. The main point is not to break something while I'm doing it (including myself). There are a surprising number of things that I have paid to have a professional do and then later had to redo it myself. Then I'm really mad that I spent the money. Now I try first and if I can't do it, happily hand it and some cash over to a pro.

 

[MarkCoburn]

Mark,

I really appreciate you documenting this with all your pictures, but there is an easier way. First you have to take off tension like RetiredIronPeddler said, then this next part is what many people miss:

1) Pull the lever on the rear of the tractor (the one to manual move the tractor). This puts the transmission in neutral and will allow the plastic cooling fan to be spun by hand.
2) Remove the idler pulley nearest to the PTO and remove it from it's mounting bracket to get the belt out.
3) Remove the belt from the pulleys and carefully route the belt up between the fan blades. If you work carefully and slowly you can rotate the fan and work the belt out. Then install the new belt the same way, by routing it over a fan blade and spinning the fan by hand, slowly working the belt down onto the pulley.

Obviously you must do this SLOWLY AND CAREFULLY or you will break the fan blades, and you get kind of twisted trying to get your arm up to reach the fan, but it does work. Sorry I don't have any pictures but when I replaced mine a few years ago this process worked perfectly and I didn't have to remove the fenders. Of course I didn't change any pulleys, so having the fenders off probably helped you with those.

P.S. --
What is the grounding wire shown in this picture?

http://coburnphoto.smugmug.com/Cate...ement/i-NXrTz7d/0/XL/img20120521201134-XL.jpg

I've never seen that wire on any 345's ...

That cable connects to my MC519 trailer. It pulls the top open as you dump the trailer. The design is for it to be securely attached to the cart and removed from the tractor when the trailer is removed. One of the previous owners connected it this way to the tractor. I think they basically never removed the trailer. I have not yet gotten the part I'll need to turn the cable back around, putting the removable part on the tractor.

 

[beenthere]

Removing the fender deck is a great opportunity to check things over AND clean out the collected debris under there. As well, can see how much debris collects under the foot pads of the deck. When that area stays wet, rust will follow.

Good set of pics. As well, a good subject title for others to find easily when searching TBN.

 

[MarkCoburn]

Removing the fender deck is a great opportunity to check things over AND clean out the collected debris under there. As well, can see how much debris collects under the foot pads of the deck. When that area stays wet, rust will follow.

Good set of pics. As well, a good subject title for others to find easily when searching TBN.

Thanks. I have recieved a bunch of help from this forum. I hope someone can get some help from this; even if it is what not to do.

 

[MarkCoburn]

part 2

I initially tried to just weave the old belt out of this guide, but it was being a pain. After unbolting it just fell off of the belt and went on the new one just as easy. I also noticed that the old belt was rubbing on one side. I made a point to center it around the new belt when re-installing.





One feature of the back two idlers is that they are bolted to a slot so that they don't need to be removed to get the belt off. Just loosen them and slide them to the side.







This is one of those, 'what not to do', photos. I started from the front and moved back, but ended up taking this front pulley back off and putting it on last. I needed that extra little slack to get over the stationary transaxle pulley and this pulley only needs a little slack to re-install.



It was super easy swapping the belts with the fenders, gas tank, and fan removed.







To put the spring back on, I used a piece of heavy wire and a ratchet strap attached to the front weight bracket (remove bumper cover to find).

This activity seems like a good way to get hurt. The spring is quite stiff and there is a bunch of stored energy when you have it stretched enough to attach.





Here is another 'what not to do' photo. I left the two idler pulleys snug but not tight, planning to torque them down later. With the belt and spring installed, I can not get to the black pulley's bolt. You might be able to put enough on it with a wrench, but I couldn't find a 15mm wrench in my tool set.



Not wanting to do the whole pull the spring forward, remove, slack, pull forward again, re-install thing; I again exploited the advantage of having the rear exposed and simply used a strap to slack the belt.





This photo is out of place, but this is how I slacked the belt when I first removed it.



I also used this method and prefer it if you are a one man show. The ratchet strap will hold it slack while you install the belt on the transaxle's pulley and re-install the front idler pulley.



While installing the front idler pulley, something didn't feel right. Looking closer, I found that the belt was not properly on the drive pulley. I could see how this could get installed like this and blow through a belt quickly.



Well, break's over, back to work on the tractor.

 

[Retired Iron Peddler]

The belt guide you refer to was the one that broke off and "rode" the belt through a pulley and broke the drive belt. The JD tech who replaced the belt told me to leave it off and I did. I've had no problems with the belt since then without the guide.

Bill

 

[hardtime]

Used this post repairing my 345 hydro belt today. Very good info, thanks.

Removed the seat assembly as shown. Glad I did because the hydro pulley nut had backed off slightly. New self locking nut was just the ticket.

 

[RSGX345]

A couple weeks ago, while replacing my PTO, I slacked the drive belt and took off the front idler. It looked to me, like weaving the belt around and onto the transaxle would be a major pain, for someone like me, who had never seen what it looks like under there. I read, in some other threads, that it was worthwhile taking off the fenders. I decided to try that and clean while I was in there.

I might be a moron, but I couldn't figure out how to get the belt off and on without removing the spring. I think I read a previous post of yours, describing the wire to the front bumper. That is what I set out to do during the PTO replacement. I'm sure I'm going to feel silly when someone explains what simple thing I missed, but I don't see how he could have just pulled the spring forward and leave it there until finished. For one thing, pulling it forward actually makes the belt tension tighter.

In short, I'm glad I did it this way. Several times, I took the advantage of being able to work from above. The 5 minutes it takes to remove the fenders and fan are well worth not having to weave the belt around it. I think I would have been able to get it from below if removing the fenders was not this simple, but I would have needed to use a bunch of swear words in the process.

I've got the new belt on now. Even with the fan, spring, and the front idler removed, the belt was very snug going over the transaxle pulley. Now that I know what it looks like up there, I'd still do it this way next time.

I try to work on our things myself, if I can. It is an additional way that I provide for my family. We can buy used equipment that saves us money and maintain what we have that also saves us money. I'd have to get a second job if we paid to have someone else maintain even what little stuff we have. It can be frustrating and rigorous working on our car, truck, tractor, etc. I try to take my time and make it as easy as possible. The main point is not to break something while I'm doing it (including myself). There are a surprising number of things that I have paid to have a professional do and then later had to redo it myself. Then I'm really mad that I spent the money. Now I try first and if I can't do it, happily hand it and some cash over to a pro.

I'm new here, bought my GX345 this June used with 475 hrs.

I had to change my drive belt and didn't have a service manual, that's how I found this forum/post. I thought I'd add my experience with this for other that want to do this.

I do all my own work as you stated, for much the same reasons. Anyway I thought I'd try the short cut method first, without taking the fenders off, it looked fairly easy. I removed all of the pulleys from underneath, but tried for while to get belt off, but I couldn't get enough slack to get the old belt off. I think if you can get the clutch pulley off you may be able to get enough slack to remove the belt from the bottom. I couldn't get my clutch off easily, so I went from the top. I could of cut belt off, but I figured it'd be impossible to get a new belt back on if I couldn't get old belt off.

I really didn't want to take everything off because I thought it'd take to long, but it's really not that bad. Once fenders are off, this make thing much easier once you get gas tank and fan blade off. I thought I'd mention I observed the same thing as you, that the nut on the fan/drive pulley was loose. You wouldn't be able to check and tighten nut without having fenders removed.

The other thing I think is worth considering is it is replacing all three of the idler pulleys, there only $13-18 ea. I believe these were original and tractor had 500 hrs. One of mine was definetly shot, loose noisy bearings. One was marginal, felt a little notchy, and the third one felt tight and smooth. But I brought it to JD dealer and asked the JD tech what he thought and he showed me why he wouldn't use the one I thought was good. The tech spun the good used bearing and it just kept rolling for a long time. He took out the new bearing and when you spin it, it doesn't hardly spin for long at all. The new one has grease in it causing rolling resistance. The used one clearly didn't have any grease left. Tech though it may last a while, but if it fails, sooner than later, could possibly ruin an expensive belt (~$75-80). I also replaced the plastic bushings and seals on the idler arm, and a new lock nut on the trans/fan pulley.

I guess the bottom line to consider is if you want this fix to last a long time, or if you don't care and don't want to spend the extra money as to how your going to try to replace the belt form the bottom only or the top.

 

[chad22]

Looks like you had a lot of fun replacing that belt. lol

I can usually replace them in less than an hour but not that one "that's for sure".

I have to replace a belt on my sears garden tractor/loader "once the belt arrives by ups" and thankfully it won't be that hard to replace.

Chad

 

[JD Power]

I just finished up on replacing the trans-axle belt. Thanks to all the posts on this subject as it made the job a lot easier to follow. I had a little grief separating the electrical connection to the PTO. I finally wiggled it apart after 15 minutes and could get the new belt up onto the drive pulley. The electrical blades in the PTO plug were really corroded tight. Used some electrical spray and put them back together quite easily. Taking the fender/seat assembly off is the best way to go. I would have missed the trans-axle input sheave pulley had all the gear splines worn away and was just about free spinning. The nut was tight and that was the only friction holding the pulley tight to the input shaft. I had read somewhere that the spline metal on the sheave pulley is softer than on the trans-axle input shaft. That keeps the input shaft splines from wearing out creating a real costly mess. It appears that spline takes a lot of the stress when turning the input shaft so you may want to check it when you get to that point.

 

[hunt4570]

So I'm way late to this, but it sounds like what I need to do

 

[hunt4570]

And I cheated.. I took it to a dealer to let them do it, I just didn't have the time.. Had them replace the leaking valve cover gaskets as well

 

[bmg88201]

Wow, I’m just a do it yourself-er and I changed my belt in about 2 hours. I didn’t take off half of that stuff to get it done. Replaced a few sheaves while I was at it. I suppose it’s good to remove all that stuff to inspect things though. This is a great forum.

 

[hunt4570]

Wow, I’m just a do it yourself-er and I changed my belt in about 2 hours. I didn’t take off half of that stuff to get it done. Replaced a few sheaves while I was at it. I suppose it’s good to remove all that stuff to inspect things though. This is a great forum.

Yeah, like I said short on time, had them replace all the idlers and fan while they were in there.. heck the thing is about 25 years old.. also did the valve cover gaskets as long as they had it.. but now I dont have to mess with it .

 

[mjw]

Yeah, like I said short on time, had them replace all the idlers and fan while they were in there.. heck the thing is about 25 years old.. also did the valve cover gaskets as long as they had it.. but now I dont have to mess with it .

Do you have the newer metal valve covers?
My dad replaced the gaskets a few years ago but still had leaks.
One of them fully let go last summer and I found out that there is an upgrade from the plastic valve covers that warp/crack and leak.

I’m rereading this thread in preparation of replacing the drive belt and fuel lines.

Fuel pump failed, old style that leaks into the hot muffler, got lucky it failed during snow season, short run time, cold temps probably helped prevent a major fire.
Bought the drive belt last season, just been to lazy to put it on.