The tracks need tightening, but I suspect that they may be wore out and at the end of their adjustment, post a few pictures of the bushings and sprockets, one quick fix is to take out a link if their not too bad and not going to use the tractor a lot.

Hi, Neil.
Yep, my 'guess' was WAY off. That would be about like foam ribber shock absorbers on a D9G though. And bear in mind that those are WW2 time period figures, not that I imagine they would have changed a whole lot throughout the production runs of those machines.

Just my 0.02.

if they are shot maybe try tillys at Toowomba, Qld never know what they have in the yard they speacilise in cat and komatsu parts. the killer would be the freight though.

The other place to try would be John Parks in Bosie Idaho he has a lot of old Cats.

www.tractorparts.com

Regatds

tillys supply new, used and reco parts and whole machines if you want. exporting worldwide. sometimes you can find what you want with a trawl on google or ebay.

Hi, What you got is a bush fix for a loose track. In my 45 years wrenching on equipment, I have done and seen this done in many ways, on various size machines. It was only recently I had seen a guy with a 215 excavator pull the idler ahead on one side frame with a chain and binders, the welded bocks behind the idler guides to hold the track tight.
Those springs can be like mini bombs!!!!!. If your spring is starting to look like its bulging in the center, take a torch and cut it in sections as much as possible before trying to remove it or do any repair around it. Unless you are ready to replace the complete spring as an unit, then I would move the idler as much as needed for track tension then weld on to the pipe or replace it with a longer pipe.
Just to give you an idea as to how powerful a track spring is, I know a mechanic who lost part of his hand while trying to assemble a D6C spring with the proper Cat tooling. One of the tooling rods failed, the spring under compression cocked in the tooling and took out the guys hand.
Another time I had to go to a customers shop to take out a D8K spring. Their mechanic didn't know the danger he faced and as to how lucky the spring never got loose and caused injury, damage or death. The mechanic did not know about threading the nut on the spring rod before removing the cover of the housing the spring is contained in. He actually sat on the track frame and began to remove the circle of bolts on the cover, while doing this the spring shoved the cover into a cocked position and jammed it in place. Lucky, Lucky man !! I went to the dozer with a 100 ton press, had a welder to fabricate a box out of 1 inch plate and weld to the frame as a base to hold the press ram. Was able then to press the cover back into place, however the bolt holes then did not line up. I then had one of their operators bring over a 966C and put the bucket lip up against the spring housing cover. Removed the press ram to make room for the cover to come out. There was that much force behind that spring that it pushed the 966C back with all its brakes locked up. I hope I didn't bore you with my story, just want to warn you, those springs are frigging dangerous. Good Luck, Dan

Here are more pic's, I got the idler in there, hows the rest of the undercarriage look?
 

From looking at the undercarriage in your photos, it is worn out, but not destroyed yet, meaning if you do your best to fix the worst problems and only use it occasionally for light work, it may be useable for some time.
I would measure the rail height and stretch the tracks tight by putting a wood block between the sprocket and track and backing the cat up until the track is under a little tension, then measure center to center across 5 links, that will tell you how much internal wear there is on the rails and help you determine how many links you would need to remove.
Tighten your loose pads, and whatever else is loose, lube the rollers and idlers and see how it does, also check to see how loose the idlers are on their shafts and anything else, rollers sprockets etc. When you have split the tracks, that is an good time to jack up one side at a time and inspect these items.