Putting track back on JD 490

[dan7]

I removed grease fitting and the 15/16 housing behind the fitting. Pushed the idler back and no grease came out. Idler just returned to its original position after I relived the presser. Now can't get track back on. Any ideas?

 

[lantraxco]

Sounds like the adjuster rod is out too far and stuck or angled and binding. Probably have to unbolt the cylinder, pull the idler,spring, and adjuster cylinder all out to get it back to moving. Might as well put new seals in while you're there if possible. Sorry.

 

[dan7]

Someone said it could be a bolt that holds the spring could have broke?

 

[lantraxco]

Possible but the way it all goes together you should get some travel out of the adjuster I would think. Either way it sounds like the whole works maybe should come out?

 

[mrappels]

i have to ask, did the track slip off? or was it routine maintenance you were doing?

 

[excavator]

If the track is off of the front idler then the bolt that goes through the spring wouldn't be broken. If it was the idler and spring would have pushed out of the track frame, usually quite quickly. Unless the spring is also broken. When you pushed the idler back in, how far in from the front of the track frame were the axle slide blocks?

 

[dan7]

The track came off. When I pushed on the idler it went in about 3 inches and came back out as soon as presser was released. I finally gotten chain back on after holding back the idler with straps. Today I tried to put grease in to tighten up the track and the idler would not move. I took the grease fitting out and it took grease, so it is not that. Thanks for the help. Any ideas?

 

[mrappels]

i agree with lantraxco that the piston part of the adjuster is possibly stuck or cocked. had it happen on a cat 390D where the rod mushroomed or stepped or something inside the barrel. not entirely sure.
we failed to pull it apart with a 100ton press.. had to get a new one lol. there are two fittings, one with the nipple and one for slackening off, guys on site only ever checked the blank one to make tyr stop it leaking. turned out the grease nipple valve (exact same design as the release valve save for the nipple) was loose and was the reason for the leak. elementary, but nobody checked it.
what tonnage is a jd490?

 

[mrappels]

so the nipple is clear, you say the idler doesnt move, does the adjuster take grease though?

 

[dan7]

No, the adjuster does not take grease. The idler moves, but it have to push against it with a dozer. When I back off on the presser, the idler just returns to its original position and no grease comes out.

 

[mrappels]

No, the adjuster does not take grease. The idler moves, but it have to push against it with a dozer. When I back off on the presser, the idler just returns to its original position and no grease comes out.

can you see if the piston/rod moves where the grease goes when you push it?

 

[dan7]

Yes it does

 

[mrappels]

Yes it does

to be honest, it doesn't make sense that the adjuster rod moves while it wont take grease..