The order we never skip — which is why the wrong part does not reach your site.
01
Confirm
Nameplate, OEM number and working conditions — checked against your machine, confirmed in writing before you pay.
02
Verify
Photos and video of the actual part, packed and labelled, before it leaves. What you see is what ships.
03
Prevent
Send the hour-meter reading and we log the service interval — you get a message before the next one is due.
04
Dispatch
Nothing leaves Xi’an until you reply "ok". You approve, then we ship — not the other way round.
Confirm this part for my machine
Machine model and part number are what let us confirm fitment in writing. Message is optional.
Overview
Fitment Note: Confirmed by the removed ring set number and the cylinder bore. Standard size for a 102 mm bore, 3 rings per piston (2 compression + 1 oil). One set per piston; tell us your engine and we confirm the total.
Engine piston ring set (standard STD) for the Caterpillar 3066 / S6K / C6.4 diesel engine family (also 3064 / C4.2) — a direct replacement for the original Caterpillar 178-6543. Bore diameter 102 mm, three rings per piston (two compression rings + one oil control ring), alloy cast iron with a plated face. They sit in the piston ring grooves and seal the combustion chamber, control oil and transfer heat.
Piston rings are engine wear items. Typical failures are excessive end gap, loss of tension, gumming / sticking and worn coating — causing poor compression, blow-by, high oil consumption, power loss and blue smoke. They are normally replaced as a full set during an engine overhaul, together with the liner and piston.
Supplied as a set per piston (three rings). Confirm the removed part number, the bore diameter (102 mm) and ring thicknesses before ordering; observe the correct end gap and side clearance, and the TOP mark orientation when fitting.
Key Features
Direct replacement for CAT 178-6543
Standard size, 102 mm bore, 3 rings per piston (2 compression + 1 oil)
Alloy cast iron with a plated face for wear resistance
Low compression, blow-by (high crankcase pressure), high oil consumption, power loss, hard cold starting, blue exhaust smoke and oil that blackens and thins.
Installation Tips
1. Check the cylinder bore, piston groove and ring end gap before fitting.
2. Fit the compression rings with the TOP / dot mark facing up; do not over-spread the rings.
3. Install the oil control ring (with its expander) in the correct groove.
4. Check the ring end gap and side clearance against the engine specification.
5. Lubricate the rings and bores, then turn the engine over by hand before starting.
