Frozen track adjuster

I assume you loosened the clamping bolts first to the adj. nut. You could try keeping some Kroil or another good spray on it and let it penetrate for a couple days & heat again & also if you can wedge a piece of iron under it then hit it with some sharp blows with a heavy hammer & sometimes breaks the rust crust on them. You may have to get some heavier heat to it to get it to loosen but try the above I mentioned first and see what happens.

If you've already got a torch, you might think about getting a "rosebud" tip for it. As they're made in various sizes, I'd choose a medium sized one. It's a tip that's not often used but when ya need a lot of heat, there's no substitute.

SJ's tips are good ones and I'll add another one. When you do get that nut loose, try jacking the idler ahead to take the force/weight off the nut before adjusting it.Most of those old bolts are not only rusted but they've had a lifetime of rocks and junk falling on 'em and the threads are beat up. If that fails, it might be time to pull the spring assembly off and if Cat doesn't have what's needed, it's time for a trip to your local machine shop to have a bolt made up. If so, have 'em make it out of 4140 or Stressproof of some similar material.

On smaller tractors, I've seen the idlers jacked out and spacers inserted. Dunno if that would work on an 8 tho'.

On some large nuts that I have tried to loosen I have drilled a hole in one of the top flats of the nut as close to center as possible (somtimes you will need a colbalt dril bit) you will need to drill deep enough to get into the threads and then mix and fill the hole with some rubbing alcohol and kerosen about 50/50 mix (an old timer told me 30 years ago that the kerosen works as a carrior to penatrate and the alcohol desolves rust) some of the nut busters are similar to this. If you have enough patience this may help get it freed up inside.
Russell

I had the same problem on my D6 9U. All the info. above is right on the money. The key here is patience. Heat that nut as hot as you can get it and wack it as hard as possible with a BFH. 😄 (Big !@#$%&*$ hammer) It may a few times of doing this, but the crud in there will eventually give way. I also agree with the rosebud tip. Get one.

hello Soumalinen,just a word of waning about pulling track spring out if you have to ,that big spring will kill you if just undo the bolt that hold it in there,you need proper tools to compress the spring to remove it,

re the nut ,as ol'_Grump say ,i would see if you can remove some tension fro the spring to help loosen the nut ,

It,s been years since I worked on one of those springs but as far as I remember you don,t do anything with the tension adjustment till it,s out & then you take it to a shop that has a heavy duty press to put it in & then take the tension off of it a little & then cut the end off of the bolt so you can release it slowly & then a new bolt will have to be installed if it can,t be used again. At the shop we did probably 100s of them over the years & that,s the way to did it and the safest.

Don't forget to clean the exposed threads you'll want to run the nut onto. Overlooking that source of thread contamination gives you a pile of dust that has to be dealt with between the nut and the rod. Kroil sprayed onto a hot thread gets drawn in as it cools. Not too hot or it just flashes away.

You're absolutely correct SJ. I'd forgotten that some folks wouldn't know about the tension on that spring. I worked in a repair shop many years go when a guy removed the idler on a D6 and just went ahead and burned the bolt off. .while it was still in the tractor😮 ! Fortunately, he didn't get hurt but that spring, plate and what was left of the bolt got launched THROUGH a brick wall, across the street and into the adjacent lot. Made quite a bang when it happened. .and caused him to go home and change his shorts😄 Didn't help the torch either, bent it up fairly well when that spring let go. .

Grump you are right, they can fly like a rocket if turned loose. Remember one time at the shop a spring bolt was broke & tightened up the track as far as it would go.I can,t just remember if they chained the idler & spring back or just cut the track to get it out but when it was turned loose that idler & attached parts & the spring assem. flew out the door for about 40 or 50 Ft.It was from a D8 if I remember but they prepared for it to fly by opening the shop big door & kept people out of the way.I don,t know why they did it that way that time as the welder usually welded bars on the spring plates to stabilize it to get it out & then put it in the big press & cut her loose.