What exactly happens when you add grease to the system? The grease fills a cylinder, pushing a piston against the front idler. The triangle form by both idlers and the sprocket gets bigger as the front idler moves out, tightening the track.
To learn more about the components of the undercarriage and how they interact, go to our comprehensive undercarriage guide.
If you notice grease coming out between the grease nipple and your grease gun when the track starts tightening up, it might mean the end of your gun is worn out and not sealing on your grease nipple. Or, the grease nipple is damaged, whether due to corrosion, debris, or a tool being on it. We recommend going for sure and replacing both.
Pump grease until the track isn’t slack on the bottom and there’s not much sag on top.