Undercarriage & wear parts
How to find the part number on an excavator part
Where the casting mark usually sits
On track rollers and idlers it is normally on the end face or the outer rim. On sprockets it is commonly on the hub face or between two teeth. On bucket teeth it is usually on the side of the tooth body, sometimes under the adapter where it is only visible once the tooth is off.
It is raised or recessed in the casting, not stamped or printed. That matters for photography — a raised number photographs best under side lighting, where the relief casts a shadow.
Reading a worn or partial number
Corrosion and peening obscure digits, and a partially read number is more dangerous than no number, because it can match a real part that is not yours. If only part of the number is legible, say so explicitly when you send it, and send the photograph rather than only the transcription. A supplier who understands casting marks can often infer the missing characters from the pattern; a supplier working from a guess cannot.
Most wrong shipments begin with a part that was ordered by machine model instead of by part number. There are three different numbers in play, and they frequently disagree.
The three numbers
- Casting number. Cast or stamped directly into the metal. The most reliable identifier, and the hardest to fake or lose.
- Label number. A sticker or plate. Convenient, but falls off, gets painted over, or refers to an assembly rather than the part.
- Catalogue number. The number in a parts book. It maps to a specific machine serial range, which is why the same physical part can carry different catalogue numbers in different markets.
If you send only one of these, we may confirm the wrong part — not because the number is wrong, but because it identifies something adjacent to what you need.
How to photograph a casting number
- Clean the surface. Grease and rust hide digits.
- Light it from the side so the raised or recessed digits cast a shadow — this is what makes them readable.
- Get close, and take a second shot slightly wider for context.
- If the number is on a curved surface, take two shots from different angles.
A phone photo of the casting mark is more useful than any written description.
When the casting number is unreadable
It happens on heavily corroded parts. In that case send:
- Machine make, model and full serial number
- The part number from any invoice or packing list
- Photos of the part on the machine, from two angles
Serial number is the fallback because it narrows the machine build to a range, even when the part itself is unidentifiable.
Send it to us
alfrun@gmail.com — we cross-check the casting number against the serial range and confirm the part number before quoting.
Before you order
Send machine make, model, serial number and a photo of the casting mark. We confirm the part number and fitment basis before any price discussion. If we cannot confirm it, we say so.
Trademark notice
Machine brand names and part numbers are used only to describe fitment and application. We are not an authorised dealer of any machine manufacturer. We do not use manufacturer logos and do not describe parts as genuine, OEM or original.
Reviewed by Zhonglei M&E parts desk — export trading partner for undercarriage and wear parts. Last updated 2026-11-13.