Clearing the way.

Bulldozing through rubble and building debris can do some real damage to the excavator's drive wheels, belt guides, scraper bars and drive belts.

Here are some PM pointers to keep in mind when you eyeball these components:

Drive Wheel

The drive wheel is NMC when more than two adjacent drive wheel spokes, more than four in a group often, or more than six total, are missing from a single drive wheel.

Take a look at the drive wheel hub for oil leaks and loose or missing mounting bolts. Enough of a leak that forms drops (a Class III leak) means the hub is out of commission.

Call in your mechanic to tighten or replace any missing hub mounting bolts. It could also mean the hub's seal needs to be replaced.

Scraper Bars

Kneel down and look at the drive wheel's scraper bar. The bar diverts mud and crud away from the drive wheel and track.

Eyeball the bar for loose or missing fasteners. Make sure the rubber flap isn't torn or missing.

Belt Guides

After inspecting the scraper bar, move over to the belt guide. Give your mechanic a heads-up if the belt guide has holes, or if there are loose or missing bolts.

New Drive Belt Info

Here's the latest check on the excavator's new drive belt (track), NSN 2530-01-503-9347. You'll find this info as a PMCS check in the updated TM 5-2430-200-10.

After cleaning crud and debris from the drive belt, eyeball the belt's guide blocks. The belt is NMC when two blocks in a row are missing, or when twelve or more are missing from the entire belt.

A Closer Look

Seventy-two steel cables run lengthwise inside the excavator's rubber drive belt. Look at the belt on both sides for exposed cable strands.

Cut an exposed cable with BII cable cutters, NSN 5110-00-541-6730, when it extends one inch past the belt. When the excavator is back at the shop, your mechanic can cut or grind the cable flush with the belt's surface.

If more than one inch of cable strand is exposed, or if 28 of the 72 cable strands are broken, the belt is NMC and needs to be replaced.

Cuts and Gouges

Clearing debris means the drive belt ends up with cuts and gouges. It's just part of the mission.

Keep an eye on any large cuts, especially when they become larger and deeper alter a day's run. The belt is NMC when it's cut across more than 40 percent or almost half the width of the track.