Model: WP12 / WD618
Part Number: 612600030054
Brands: Weichai Power
Engine Model: WP12, WD12, WD618, WP12.430, WP12.460
Engine Type: Diesel
Scope of application: heavy trucks, mining dump trucks, construction machinery, marine and generator engines
Modern diesel pistons run hot, and the ring pack has to seal against pressures that rise sharply with load. On the Weichai WP12 and WD618, ring set 612600030054 is matched to the piston used across the 12-litre range. It contains two compression rings and one oil control ring, with ring thickness and radial tension chosen for the piston groove geometry of this engine.
Rings are the cheapest part of an overhaul and the easiest to get wrong. A set with the wrong tension, or one installed with incorrect end gaps, will either burn oil from day one or scuff the liner within the first few hundred hours.
The set fits WP12 and WD12 road engines and WD618 industrial and marine variants, including heavy tractors, 8x4 mining dump trucks, large loaders and generator sets. Because piston design changed across production years, always confirm the piston part number before ordering rings. A ring set that suits an early piston may sit too tight or too loose in a later groove.
If the liner shows a ridge at the top of ring travel, replace the liner rather than fitting new rings into a worn bore.
A leak-down test tells more than a compression test alone: it separates ring leakage from valve or head gasket leakage in a single measurement.
Markings on the rings indicate the upward face. Fitting a tapered ring upside down pumps oil into the combustion chamber, which looks exactly like a failed turbo seal.
The three parts work as a system. Ordering a matched set from one supplier removes the guesswork and avoids the situation where rings fit the piston but do not suit the liner finish. If you already have pistons, give us their part numbers and we will supply rings and liners that match.
Air filtration and oil quality determine ring life. Replace the air filter at interval, check intake hoses for cracks and use the specified oil grade at the severe-duty interval. Avoid long idling in cold weather, because low cylinder temperature glazes the bore and prevents rings from sealing properly.
On a 12-litre diesel, the oil control ring does more than stop blue smoke. Oil that passes the rings burns in the cylinder and raises particulate emissions, which matters in markets with emission testing. A worn oil ring increases oil consumption gradually, and the first sign is often a slight haze in the exhaust under load rather than visible smoke.
Compression rings and oil rings wear at different rates. It is common to find compression rings still within tolerance while the oil ring has lost tension and the expander is flat. For that reason, always replace the full set rather than only the visibly worn rings.
Yes, one set covers one piston with two compression rings and one oil control ring.
Only if the groove dimensions and ring thickness match. Check the piston part number with us first.
Moderate load cycles with varying speed, no long idling, then change oil and filter after the first few hours.
Usually glazed bores, rings fitted upside down, or the wrong end gaps. Recheck the markings and the bore finish.
Browse the Weichai piston and components category, and pair these rings with the WP12 cylinder liner 612630010055 or the WP12 cylinder head 612630040001.
Weichai WP12 Piston Ring (612600030054). The ring set seals combustion, controls oil and conducts heat from the piston into the liner. Each of the three rings does a different job with a different face treatment.
Measure the old ring thickness and radial depth against the new set. A set that fits the groove loosely will flutter and break rather than seal.
Numbers beginning 6126 belong to the generation shared with the WD618 and early WP12 engines. Parts in this block were revised several times, so the casting or housing is the reliable identifier rather than the number alone. On this engine, confirm the WP12 application against the engine plate before ordering.
Measure end gaps in the bore the ring will actually run in, with the ring squared by the piston crown. Measuring at the top of the bore or in a different liner gives a false reading.
Ordering note. Packing is export grade: each unit is wrapped, boxed and palletised for sea freight, with the part number marked on the outside so the receiving store can book it in without opening the carton.
Related reading: Piston Ring Selection: Gap, Tension and Bore Condition
| We Are 30 Years Diesel Engine Parts Supplier | |
| Brand | EPID |
| Warranty | 12 Months |
| Condition | 100%New |
| More Models | Weichai: WP12, WD12, WD618, WP12.430, WP12.460, and other Weichai series. |
| Shipping | By sea / air / express (DHL, FEDEX, TNT, UPS, EMS) |
| Packing | Standard exporting packing or as required |
| Payment Term | L/C, T/T, Western Union, Trade Assurance |
| Delivery Time | 3-7 days (depend on order) |
| Selling Point | 1. On-time Delivery 2. Genuine Quality Assurance 3. Professional Supplier |
If the liner shows a ridge at the top of ring travel, replace the liner rather than fitting new rings into a worn bore.
A leak-down test tells more than a compression test alone: it separates ring leakage from valve or head gasket leakage in a single measurement.
Markings on the rings indicate the upward face. Fitting a tapered ring upside down pumps oil into the combustion chamber, which looks exactly like a failed turbo seal.
The three parts work as a system. Ordering a matched set from one supplier removes the guesswork and avoids the situation where rings fit the piston but do not suit the liner finish. If you already have pistons, give us their part numbers and we will supply rings and liners that match.
Air filtration and oil quality determine ring life. Replace the air filter at interval, check intake hoses for cracks and use the specified oil grade at the severe-duty interval. Avoid long idling in cold weather, because low cylinder temperature glazes the bore and prevents rings from sealing properly.
On a 12-litre diesel, the oil control ring does more than stop blue smoke. Oil that passes the rings burns in the cylinder and raises particulate emissions, which matters in markets with emission testing. A worn oil ring increases oil consumption gradually, and the first sign is often a slight haze in the exhaust under load rather than visible smoke.
Compression rings and oil rings wear at different rates. It is common to find compression rings still within tolerance while the oil ring has lost tension and the expander is flat. For that reason, always replace the full set rather than only the visibly worn rings.
Browse the Weichai piston and components category, and pair these rings with the WP12 cylinder liner 612630010055 or the WP12 cylinder head 612630040001.
Yes, one set covers one piston with two compression rings and one oil control ring.
Only if the groove dimensions and ring thickness match. Check the piston part number with us first.
Moderate load cycles with varying speed, no long idling, then change oil and filter after the first few hours.
Usually glazed bores, rings fitted upside down, or the wrong end gaps. Recheck the markings and the bore finish.
EPID supplies diesel engine parts for Weichai, Baudouin, Yuchai, Caterpillar, Sinotruk, FAW Xichai and Cummins engines. Every order is checked against the original part number before packing, and our team can identify a part from a photo of the engine plate. Ask for a quotation with your model and quantity and we will reply within one working day.
