Model: WP6
Part Number: 13031181
Brands: Weichai Power
Engine Model: WP6, WP6G, WP6H
Engine Type: Diesel
Scope of application: light and medium trucks, buses, agricultural machinery, generator sets
The crankshaft converts combustion pressure into rotation and delivers torque to the flywheel. In the WP6 it carries four or six connecting rods depending on the version, drives the oil pump and camshaft through the front gear train and absorbs torsional vibration through the damper. Part 13031181 is the shaft used in this mid-range family.
Shaft condition decides whether an engine can be rebuilt at all. Journals that are out of round, a shaft bent by a hydraulic lock or a damaged thrust face will destroy bearings within minutes and can crack the block.
The shaft fits WP6, WP6G and WP6H engines in light and medium trucks, buses, tractors and small generator sets. These engines are common in Africa and Southeast Asia, often in continuous duty with limited maintenance. Confirm the engine plate and the old crankshaft number, since pulley and flywheel details differ between variants.
Shafts are forged, heat treated, shot peened and nitrided before final grinding. Journal diameter and ovality are measured at several points, fillet radii are verified because cracks start there, and run-out is checked on centres. The thrust face is measured for flatness and finish, which control end float and oil loss.
Shafts ship in a braced crate with journals sleeved. Tell us before dispatch if you need an undersize.
A knock under load that fades at idle is the classic warning. By the time it is loud, the journal is usually already damaged and the bearing is close to spinning.
Match the part number, the journal size and the shells you plan to fit. Mixing a reground shaft with standard shells guarantees failure. Give us the bearing part numbers and we will confirm compatibility before shipping.
WP6 crankshafts and bearing shells are lapped to each other in service, so a shaft fitted with mismatched bearings fails quickly. Early and late shafts can differ in damper fixing, and a shaft from the wrong variant will not accept your existing pulley. Photographs of the old shaft ends resolve the question faster than any catalogue lookup.
Shafts are bolted into braced timber crates with journals sleeved and lifting points marked. Freight is charged on weight and volume, so tell us whether the shaft travels with a block so we can plan the load and reduce cost.
Lubrication and vibration control decide crankshaft life. Use the specified oil, change it at the severe-duty interval, keep the oil cooler clean and never run with a leaking injector that dilutes the oil. After a hydraulic lock or a broken damper, check straightness before reuse.
A lightly scored journal can be polished if the damage does not exceed the limit. Deep scoring or heat discoloration means hardness is gone and polishing only hides the problem. Grinding to an undersize is possible where shells exist in that grade, but each grind removes hardened layer. For export rebuilds a new standard shaft is usually the safer choice.
Main and rod shells come in standard and undersize grades, and the grade must match the journal after any regrind. Always check clearance with plastigauge rather than trusting the marking on the box, because one undersize journal among six is easy to miss during assembly and will fail within a few thousand kilometres.
Keep shells paired with their caps and fit them clean and dry on the back. Oil or grit between shell and cap changes the crush and the clearance, and that is exactly where bearing failures start. Record the clearances for every journal so the next rebuild has a reference.
Yes, journals and fillets are nitrided.
Only if enough hardened layer remains. Most buyers prefer a new standard shaft.
Strongly recommended with a new shaft.
Mount on centres and measure run-out at the centre journal.
Explore the Weichai crankshaft category, and complete the bottom end with the WP6 connecting rod 12160519 or the WP6 engine overhaul kit 13032095.
Weichai WP6 Crankshaft (13031181). Everything the engine produces passes through this shaft. Journals, fillets and the damper interface all decide how long the bearings survive, and all three are measurable before assembly.
Photograph both ends of the old shaft with a ruler alongside. Damper fixing, flywheel flange and pilot bore differ between production periods even when the journals are identical.
Numbers beginning 1303 belong to the WP6 family. WP6 parts are compact but heavily loaded, and the mounting faces differ between production batches. On this engine, confirm the WP6 application against the engine plate before ordering.
Fit a new torsional damper with the shaft. A perished damper sends the same oscillation into the new crankshaft and cracks it at the fillets.
Ordering note. Warranty is twelve months against manufacturing defects. Failures caused by incorrect clearance, overheating or debris are assessed on the returned part rather than refused outright.
Related reading: Crankshaft Inspection: Journals, Fillets and Regrinding
| We Are 30 Years Diesel Engine Parts Supplier | |
| Brand | EPID |
| Warranty | 12 Months |
| Condition | 100%New |
| More Models | Weichai: WP6, WP6G, WP6H, 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 |
Shafts are forged, heat treated, shot peened and nitrided before final grinding. Journal diameter and ovality are measured at several points, fillet radii are verified because cracks start there, and run-out is checked on centres. The thrust face is measured for flatness and finish, which control end float and oil loss.
Shafts ship in a braced crate with journals sleeved. Tell us before dispatch if you need an undersize.
A knock under load that fades at idle is the classic warning. By the time it is loud, the journal is usually already damaged and the bearing is close to spinning.
Match the part number, the journal size and the shells you plan to fit. Mixing a reground shaft with standard shells guarantees failure. Give us the bearing part numbers and we will confirm compatibility before shipping.
WP6 crankshafts and bearing shells are lapped to each other in service, so a shaft fitted with mismatched bearings fails quickly. Early and late shafts can differ in damper fixing, and a shaft from the wrong variant will not accept your existing pulley. Photographs of the old shaft ends resolve the question faster than any catalogue lookup.
Shafts are bolted into braced timber crates with journals sleeved and lifting points marked. Freight is charged on weight and volume, so tell us whether the shaft travels with a block so we can plan the load and reduce cost.
Lubrication and vibration control decide crankshaft life. Use the specified oil, change it at the severe-duty interval, keep the oil cooler clean and never run with a leaking injector that dilutes the oil. After a hydraulic lock or a broken damper, check straightness before reuse.
A lightly scored journal can be polished if the damage does not exceed the limit. Deep scoring or heat discoloration means hardness is gone and polishing only hides the problem. Grinding to an undersize is possible where shells exist in that grade, but each grind removes hardened layer. For export rebuilds a new standard shaft is usually the safer choice.
Main and rod shells come in standard and undersize grades, and the grade must match the journal after any regrind. Always check clearance with plastigauge rather than trusting the marking on the box, because one undersize journal among six is easy to miss during assembly and will fail within a few thousand kilometres.
Keep shells paired with their caps and fit them clean and dry on the back. Oil or grit between shell and cap changes the crush and the clearance, and that is exactly where bearing failures start. Record the clearances for every journal so the next rebuild has a reference.
Explore the Weichai crankshaft category, and complete the bottom end with the WP6 connecting rod 12160519 or the WP6 engine overhaul kit 13032095.
Yes, journals and fillets are nitrided.
Only if enough hardened layer remains. Most buyers prefer a new standard shaft.
Strongly recommended with a new shaft.
Mount on centres and measure run-out at the centre journal.
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.
