OC-6 question

[Hap420]

Hey all, I have a an OC-6-68 diesel that I can not seem to get to travel in a straight line. I have a manual and can't find anything in there about keeping it straight. I want to be able to pull a one way disk tiller with it but it wont stay straight and I know it's not the plow because my John Deere 420 pulls it just fine. It doesn't stay straight even without anything behind it and I have adjusted the brake bands properly. Is this just typical of the differential type steering or is there some way a can adjust the tracks?
Thanks a lot, John

 

[TomA in CA]

One track is probably worn to greater pitch than the other. You could check this by stretching each track with a block in the sprocket and backing up. Measure pitch across 4 links, compare one side with the other. I'll bet one is longer. Turning pins and bushings or installing new will fix it. I don't know what the pitch is but maybe someone at www.cletrac. org does.

I would think with the diff steering you could compensate for this.

Tom