Mini Excv. w/ popping noise

[ioilyouin]

Gentlemen,

I recently purchased a used '06 Kubota U 35 with 1650 hrs sight unseen. When I recieved delivery the first thing I noticed was a loud popping noise comming from one side of the tracks. This noise occurs when they are running in either direction and while turning. It also occurs when the weight is off the tracks. When I run the track while suspended, slowly, I notice that it tends to load up and slow down and then pop, it speeds back up.

Since the noise occurs while the weight is off the tracks I would have to rule the rollers on the bottom out. I popped the track off and ran the motor by itself and did not hear said noise. I checked the idler opposite the drive motor and it turns freely with no growl or grind. There is also not any excessive wear on either side of the wheel to indicate that it is not running true with the drive motor. However I think that there is and excessive amount of side to side in the slide that the idler sits in.

We originally diagnosed the problem as the drive motor end, then after close inspection we changed our minds to believe that the idler was the culprit. After removing both tracks, not finding anything blaringly obviously out, nor finding either side to be more wore than the other I cannot point my finger at the idler either.

The strange thing is that the side that is not making the noise seems to be more wore than the other. The tracks are not new but I don't believe them to be the originals either. We have not owned a track machine for more than 40 years so we are born again virgins in this territory. I am looking for some direction in this matter. Is it a wise idea to switch sides with the sprockets and see if the problem switches sides as well? You input and support is greatly appreciated.

[ARP]

Did you check to make sure that your tracks were adjusted to the proper tension? A loose track could skip over the cogs on the sprocket and occasionally catch causing the binding that you notice. Just the skipping itself would make a noticeable sound.

[ioilyouin]

Forgot to mention that, yes they were within specs.

[ioilyouin]

sprocket in question
http://i571.photobucket.com/albums/ss157/ioilyouin/DSCN2804.jpg
Sprocket in question
http://i571.photobucket.com/albums/ss157/ioilyouin/DSCN2805.jpg
Idler in question
http://i571.photobucket.com/albums/ss157/ioilyouin/DSCN2803.jpg

[minimax]

Does it make the nosie with the track off the drive motor? and are both tracks the same?

minimax

[Dirtman2007]

Just looking at the picture it would appear that they did not change the sprockets when they changed the tracks. We just changed the tracks on our mini and that sprocket is pretty well worn down, I'd say 50% or so.

[wanabe]

Sounds like a bad final drive or track motor to me.

[cretecorp]

Have you tried switching the track from the good side to the side making the noise? We had a similar problem that ended up being a bad track that had broken belts inside. On the outside the track looked fine, but when you rolled it around off the ground you could see the track becoming tighter and then looser as it rolled past the bad spot.

[wellbuilt]

I think the popping noise could be a worn sprocket /broken tooth skipping or a broken belt in the track.
The track will stretch and slip off the sprocket. (You should see the track skip)
switch tracks and see if the noise changes sides . 1600 hours is not a lot of time on a machine . You should go 3000 hrs before you need parts . I just changed my tracks I had a broken belt . John

[P.Services]

Have you tried switching the track from the good side to the side making the noise? We had a similar problem that ended up being a bad track that had broken belts inside. On the outside the track looked fine, but when you rolled it around off the ground you could see the track becoming tighter and then looser as it rolled past the bad spot.

i am with this guy, i almost would bet he is right.

put the track on and then pump the mother full of grease, get it tight tight tight tight!!! and then spin it around and you will see one gap in between the lugs will be stretched way out because the belt is broken right there.

[P.Services]

cretecorp, that sk650 is a bad little machine isnt it? i loved the one i ran. the two controls for the drive functions took a bit to get used to but after a half day i loved it. i have a ditch witch zahn r300 and its a pretty sweet little tool

[ioilyouin]

The drive motor does not make the noise by itself. Also there are no broken teeth in the sprockets. The tracks appear to be a pair to me. I believe the machine was in a rental fleet. I know that approximately 1000hrs is the life of a track loader belt, but even for a rental excavator 1600 hrs seems to soon to be having problems. I would assume that the trakcs were in use only about 30-35% of the time.

[P.Services]

its the tracks, a steel belt is broke inside. put the good track on the bad side and i bet you it works fine. order up a track! try out jdskidsteer on this site, he may be able to get you a "well priced" track for it.

his user name is jdskidsteer just use the search function on his name.

[cretecorp]

Picasso, you are right the SK650 is an animal. Thanks to this forum I demo'd it last and did not make the mistake of buying a Boxer. The Vermeer was a close second and if the S800 was out at that time, I probably would have purchased it.

[P.Services]

i did get it stuck a few to many times. if i owned one i would put a little atv winch on it. i was using it in the mud and swamps for silt fence though.

[Kepple Services]

I had something similar happen to my T300, it was that the sprocket was worn down to much, and the tip of the tooth was hitting right in the middle of the lug on the track, so it would tighten up, pop, then be loose again. Once the sprocket was changed the problem went away.

[bobcatuser]

When the sprockets are this worn the u/c starts to make some interesting noise.:laugh:



One thing to check is the pitch measurement. The previous owner may have installed the wrong tracks for the machine.

[bobcat_ron]

When the sprockets are this worn the u/c starts to make some interesting noise.:laugh:



One thing to check is the pitch measurement. The previous owner may have installed the wrong tracks for the machine.

That is the worst example I have ever seen!!!!!!

[ioilyouin]

UPDATE:

I swapped the tracks this morning to check two suspects, the broken track and worn sprocket. I tightened them up and ran around the yard for a few minutes. The problem has either gone away or has diminished significantly. I hope that this is the end to this issue. Thanks for all you input.