420C track alignment

[Cubby267]

Asking for some advice on my 420 track alignment. After getting my barn find up and running I adjusted the track tension to achieve the 1&1/2" sag. I set all the tensioning nuts (inside and outside) to the same measurement from the spring tensioning lock nut. I seem to be running to the outside of the idler on both sides now. Reading the book it said to adjust the tensioning nuts (so they will be uneven inside to outside) to achieve centering on the idler after about 100 feet of straight forward crawl on level ground. Since I set all adjustments to the same measurement from the spring head is this a sign of track rail and roller misalignment? I will try to get it centered using the adjusting nuts next week. Just looking for advice if this is common or do I need to dig into rails. Thanks for any advice.

[Lavoy]

Alignment is the only important thing, where the nuts are is not. Adjust so the idler runs centered.
Lavoy

[Cubby267]

Thank you Lavoy. It is raining pretty much all week, I will get after it when the skies clear up!

[Cubby267]

Well I dropped the blade to get access to the idler adjustments. I doesn't make sense to me but i finally got the tracks centered on the idlers. I tried angling the idler in the direction of the overrun and that made it worse. Moving the adjustments so the idler angled toward the side that was running tight brought the tracks into alignment. I am about 1/4" difference for the measurement from the adjusting nut to the spring head. As Lavoy explained that measurement is unimportant as long as the tracks run centered on the idler. Visually the tracks look straight and it sounds a little smoother when crawling. A lot of adjusting to get things running centered and get the sag to 1&1/2" as the book recommends. Thanks for the expertise Lavoy. Now it's back to building roads and dragging logs!
Another question for those with carb expertise. Is the typical 1 turn on idle and 1&1/2 turn on the main a good starting place for the carb adjustments? I have a bit of a funky idle and it idles the best with the idle jet screwed completely in (closed). Is that telling me I have something plugged or worn out jets? I pulled the idle needle out and it looks OK. It runs great working under load just a goofy idle. I guess it is time to pull the carb and give it a once over!

[Lavoy]

All the way in means that you are otherwise lean at idler, in is no air, opposite of what you would think on other carbs. Yes, probably time for a clean and kit.
Lavoy

[Cubby267]

Thanks Lavoy. I pulled the carb and pulled both jets, checked the float and needle valve and cleaned. Now it idles nice with the idle screw out about 3/4" of a turn. I must have had some crud somewhere although I didn't notice anything significant when I had it apart.
I truly appreciate all the help/expertise from this site! It makes ownership of my early JD crawler fun rather than frustrating!!!!