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Selection, inspection, troubleshooting & maintenance guides · updated regularly

Field Case: A CAT 320D Jump-Started Every Morning — the Culprit Was a Regulator, Not the Batteries

Two batteries in two months, same dead morning starts. A 30-second voltage check showed no charging at all: th

Field Case: 320D Alone Wasn't Enough — the Serial Number Nailed the Right Final Drive in 3 Days

Same CAT 320D, different serial ranges — different ring gear bolts. One serial number photo locked the exact p

Field Case: A CAT 330D Boom Cylinder That Ate Three Seal Kits — the Fourth Fix Lasted

Three seal kits, three leaks. The fourth time we asked for a photo of the cylinder head: a dented, scored bore

Field Case: A CAT 336D Boom That Drifted Down — One Hold Valve Ended a Six-Month Nuisance

The boom sank ten-plus centimeters in half an hour under load; the local verdict was “cylinder leaking interna

Field Case: A CAT 336D That Ate Three Sensors — One Question Found the Real Culprit

The customer came back for the same pressure sensor a third time. We asked how long the last one lasted — the

Field Case: A CAT Dozer Down on Site — Spares Planned in Advance Cut Downtime to Two Days

The customer had pre-quoted the cooling trio (water pump, thermostat, belt) before major service. When the pum

CAT 320 & 330: The Replacement Parts Fleets Order Again and Again - WOYUANTE Parts

Fast-moving CAT 320 and 330/336 excavator parts: filters, undercarriage, cylinder seal kits, pins and bushings

CAT & Volvo Part Number Guide: How to Read and Order the Right Part - WOYUANTE Parts

How CAT (XXX-XXXX) and Volvo VOE part numbers work, how to cross-reference aftermarket numbers, and how to avo

When Does an Excavator Engine Need an Overhaul? 5 Checks Before You Decide - WOYUANTE Parts

Blue smoke, oil consumption, low compression, blow-by and metal particles: five field checks that tell you whe

Engine Surges Under Load Then Recovers? Air Is Getting Into the Fuel Line — Check These Three Spots

Power fading mid-task, RPM surging like breathing, fine again after a rest — classic air ingress on the suctio

Diesel Hard-Start Checklist: Glow Plugs, Fuel Shut-Off Solenoid or Starter — What to Check First?

Hard cold starts, cranks-but-no-start, or nothing at all — three different failures with three different suspe

Milky Hydraulic Oil: Find the Water Source Before You Change the Oil - WOYUANTE Parts

Why excavator hydraulic oil turns milky (water ingress), the three usual entry points — oil cooler, cylinder w

How to Diagnose an Excavator Hydraulic Pump Problem: The 4-Step Field Method - WOYUANTE Parts

Listen, look, test, eliminate: a practical 4-step field diagnosis for excavator main hydraulic pumps — which p

7 Signs Your Excavator Hydraulic Pump Is Failing (Check These First) - WOYUANTE Parts

Slow cycle times, whining, hot oil, drift: the seven most common symptoms of excavator hydraulic pump failure

Excavator Display Goes Black Then Comes Back? Don't Buy a New Screen — It's Usually the Main Relay or Ground

Mid-work blackouts that fix themselves are maddening — but intermittent power faults are 90% main-relay contac

No Part Number? How to Photograph a Part for a Fast, Correct Quote - WOYUANTE Parts

The three photos that let a supplier match your excavator part without a number: overview, stamped codes close

How Excavator Parts Are Packed and Shipped from China (Air vs Sea) - WOYUANTE Parts

Packing standards for excavator parts export: labeled bags, cartons, wooden crates for castings; air vs sea sh

Why Cheap Hydraulic Seal Kits Fail Early: Shore Hardness and Quality Checks - WOYUANTE Parts

How to tell a quality hydraulic seal kit from a cheap one: NBR vs PU materials, Shore A hardness, trimmed lips

Excavator Travel Motor / Final Drive Troubleshooting: the 4-Step Field Check - WOYUANTE Parts

Diagnose one-side tracking, weak travel and noisy final drives in four steps: track comparison, oil inspection

Undercarriage Wear Limits: When to Replace Rollers, Idlers and Sprockets - WOYUANTE Parts

Field wear limits for excavator undercarriage parts: track rollers, carrier rollers, idlers, sprockets and tra

Undercarriage Wearing Out Fast? 70% Is Tension and Habits — a Field Guide to Saving Money

Undercarriage is thirty percent of an excavator's upkeep. Leaking rollers, uneven track wear and early bushing

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