Track Throwing...

[panicbutton]

I changed the front idler which was worn badly, added correct shims for idler arms, measured to make sure that the idler was centered... Now I can get about 4 hours of use before same track gets thrown.

The other side has never thown a track, but it's slack is less than 3/4", it does jump the bottom rollers every once and a while. I'm thinking that I need to tighten up the slack from the factory recommendations. Any thoughts?

[Lavoy]

Check all the bottom rollers to make sure there are no flanges missing. Other than that, you might be due for pins and bushings. I know a friend of mine fought a 420 for a long time, replaced idler bushings and shafts, etc, all to no avail. Finally I rebushed his tracks, and problem solved.
Lavoy

[mini kahuna]

Lavoy is correct,check very closely for any worn down or broken off roller flanges,if you don't find anything,your pins and bushings are probably worn allowing the track to "snake" side to side and roll off the front idler.
trying to run the tracks "tight" will not solve the problem,it will put tremendous stress on final drive bearings and other parts.

[panicbutton]

Checked the roller flanges and none are chipped or missing. How freely should the bottom rollers turn? Mine do not roll that easy. Will check on the pins and bushings, I am thinking those might be worn as the track snakes alot.

Lavoy do you have the JD266 track guage tool or something similar?

[Lavoy]

I have one for a pattern, was looking at getting them made at one time, but the laser time to have the wording etched in was astronomical, so dropped the idea.
Lavoy