Tools & consumables
- Basic hand tools: metric sockets, ratchets, extensions, breaker bar, torque wrench (0–200 Nm), torque-angle gauge if required, combination wrenches, pliers, screwdrivers.
- Engine support: engine hoist or support fixture and transmission jack or engine cradle.
- Lifting: floor jack, heavy-duty jack stands, wheel chocks.
- Engine internals: engine stand (recommended), piston/ring compressors (if removing pistons), soft-jawed vise.
- Measuring: micrometer (0–100 mm), outside micrometer for journals, inside bore micrometer or dial bore gauge, Plastigage, feeler gauges.
- Press & pullers: hydraulic press for bearing/shaft work, harmonic balancer puller, flywheel/torque converter puller.
- Cleaning: solvent, lint-free rags, nylon brushes, compressed air.
- Assembly/installation: bearing installation drift or appropriate tool, locking pliers for caps (if used), seal drivers.
- Replacement hardware & parts: main bearing set (standard or undersize), main bearing cap bolts (replace if manufacturer specifies one‑time/tension bolts), crankshaft oil seals, oil pump gasket and pickup screen if worn, oil & filter, gaskets/sealant.
- Lubricants: engine assembly lube, anti-seize, thread locker where specified.
- Safety PPE: gloves, eye protection, steel-toe boots.

Safety precautions
- Work on level ground, chock wheels, disconnect battery negative terminal.
- Support engine/transmission properly before removing mounts; NEVER rely on a jack alone—use jack stands and an engine hoist/stand.
- Drain engine oil and coolant into approved containers; dispose per regulations.
- Wear eye protection and gloves for chemical/metal work. Keep hands clear when using presses and hoists.
- Mark and tag all electrical connectors, hoses, and bolts to avoid mix-ups.
- If you’re unsure about torque-to-yield bolts or press work, stop and consult the official Hino workshop manual.

Overview of the job
Replacing main bearings requires removing the oil pan, main caps and often the crankshaft from the engine to inspect journals and fit new bearing shells. It may be performed with the engine in the vehicle if access allows, but best practice is to remove the engine and mount it on a stand for controlled, accurate work.

Step-by-step procedure
1) Prepare vehicle and remove engine ancillaries
- Park, chock, disconnect battery.
- Drain engine oil and coolant.
- Remove air intake, intercooler piping (if applicable), alternator, power steering pump, A/C compressor (support or remove), accessories that block removal.
- Remove fan, fan shroud and radiators as required to access front timing cover.
- Label and disconnect fuel lines, vacuum lines, electrical connectors.

2) Remove timing front cover & accessory drives
- Remove timing belt/chain cover, timing belt/chain components per engine design. Lock the crank and cam timing as per manual to avoid cam movement (mark timing).
- Remove harmonic balancer/damper using puller.

3) Remove oil pan and oil pump
- Remove oil pan bolts, drop oil pan (cut through RTV if needed), remove oil pickup and pump (careful—pump may be held by hidden bolts).
- Inspect pan for metal debris (retain pieces for inspection).

4) Support the crank and remove connecting rods/pistons (if required)
- If replacing mains only and the crank can be removed without removing pistons, you still must ensure pistons/rods are not damaged. Many technicians remove pistons to avoid damage during crank removal — follow method appropriate to engine.
- If removing pistons: mark rod caps and journals, use rod cap bolts carefully, compress rings, remove pistons.

5) Remove main caps and crankshaft
- Mark main caps and their orientation/position (cap #1, #2, etc.). Note alignment dowels.
- Loosen main cap bolts in a crisscross sequence gradually to avoid distortion. Remove caps and bearing shells.
- Carefully lift crankshaft out (requires two people or hoist). Place on padded bench or engine stand.

6) Inspect crank journals & bearing shells
- Clean crank and mains thoroughly with solvent. Inspect journals for scoring, pitting, taper or out-of-round.
- Measure journal diameters with micrometer and measure main bore diameters with dial bore gauge to determine clearance.
- Compare measurements to bearing manufacture specs to choose standard or undersize bearings.
- Inspect bearing shells for heat discoloration, embedded debris, scoring — these indicate causes (oil starvation, contamination).

7) Machine work if required
- If journals are scored beyond allowable tolerance or undersized beyond available bearing sizes, crankshaft machining (grinding and rehoning bores or line-boring mains) is required. This requires sending crank to machine shop.
- Also check block main bore alignment; if misaligned, line-boring may be necessary.

8) Clean and prepare for reassembly
- Clean main caps, block saddles, journals and oil passages with solvent; blow out passages with compressed air.
- Deburr oil holes and pickup screen; replace pickup screen or oil pump if clogged/damaged.
- Fit new OEM-spec bearing shells into caps and saddles with correct orientation (oil groove and tang alignment).
- Coat bearing surface lightly with engine assembly lube.

9) Fit crankshaft & check clearances (Plastigage method)
- Place crank in block with assembly lube on journals.
- Cut 1–1.5 mm strips of Plastigage, lay across journal on crank.
- Install main caps with new bolts (if specified) and torque in stages to the specified torque (refer to Hino manual). Do not rotate crank while Plastigage installed.
- Remove caps and measure flattened Plastigage width against chart to determine clearance. Clearances must match workshop manual specs.
- If clearance out of spec, choose different bearing undersize or have crank reground.

How to use Plastigage & measuring tools
- Plastigage: put one strip across middle of journal, install cap and torque to spec, remove cap only (do not move crank), compare width to chart. Replace any bearing used for Plastigage measurement (do not reuse).
- Micrometer: measure journal diameter at multiple points and directions; average and compare to factory spec.
- Dial bore gauge: set to standard micrometer reading, measure main bores for taper and out-of-round; difference indicates bore problem.
- Torque wrench: use correct wrench and torque sequence; if bolts are torque-to-yield, use new bolts and angle gauge as specified.

10) Final assembly of bearings and crank
- Install new bearings (saddles and caps) with tangs aligned; apply assembly lube.
- Carefully set crank in place and install caps in numbered order. Tighten bolts in specified sequence and torque/angle to the exact values in the Hino workshop manual. Do this in incremental steps.
- Check main bearing end-play (thrust) if applicable using dial indicator on thrust face; compare to spec.

11) Rebuild remaining components
- Reinstall oil pump (replace gaskets), oil pickup, oil pan with new gasket/sealant, torque pan bolts to spec.
- Reinstall timing components, chain/belt and tensioners with correct timing marks.
- Reinstall harmonic balancer, accessories, engine mounts, reconnect lines and wiring.
- Replace oil, oil filter and coolant.

12) Pre-start & break-in
- Prime oil system: crank engine with fuel/ignition disabled or use oil pump priming tool until oil pressure stabilizes.
- Reconnect battery. Start engine and monitor oil pressure and leaks. Idle and bring to operating temperature watching for abnormal noises.
- Follow recommended break-in procedure for bearings (generally avoid high load/rpm for initial period), monitor oil condition and pressure.

Common pitfalls and how to avoid them
- Using incorrect torque values or sequence: always use manufacturer specs; improper torque leads to bearing failure.
- Reusing torque-to-yield bolts: replace if specified—these stretch and will fail if reused.
- Dirt and contamination: clean everything; even a small particle will score bearings.
- Incorrect bearing orientation or wrong bearing type: align oil grooves/tabs properly and verify part numbers.
- Not measuring journals/bores: guessing sizes leads to wrong clearance; measure and choose appropriate bearing undersize.
- Forgetting to prime oil pump: causes immediate oil starvation on first start.
- Rotating crank against tightened caps: can scrape Plastigage and give false readings; never rotate when Plastigage is installed.
- Not checking crank for twist/taper: measuring only diameters can miss out-of-round; use dial bore gauge.
- Improperly seating or aligning main caps: caps must go back to their original position and orientation; use alignment dowels and marking.
- Reusing old bearings used as measurement samples or damaged during measurement—always install new bearings for final assembly.

Replacement parts typically required
- Main bearing set (standard or appropriate undersize)
- Main bearing cap bolts (if specified single-use)
- Crankshaft oil seals (front and rear)
- Oil pump gasket and pickup screen (recommend replacement)
- Oil pan gasket/RTV and oil filter
- Engine oil and coolant (if drained)
- Any rod bearings or piston rings if removed/inspected and worn

Notes & final recommendations
- Always consult and follow the exact Hino Dutro WU/XZU Workshop Manual for torque specs, torque sequences, bearing clearances, and any engine-specific special tools or procedures.
- If crank journals require machining, use a reputable machine shop and ensure bearings selected match the ground size.
- When in doubt on alignment or if you detect significant wear/damage, remove the engine to a bench and consider professional machine work.
rteeqp73

Hino Dutro 2022 | 300 series |Turbo intercooler price & Specifications Hino Dutro 2022 | 300 series |Turbo intercooler price & Specifications #hino #commercialtruck #hinodutro.

HINO XZC710 || HINO 300 PRO || 4,009cc EURO 3 ENGINE 156HP & 460nm TORQUE [MALAYSIA SPEC] Model: Hino XZC710 Body: Chassis Cab (bare chassis) Condition: Brand New Truck (ckd by Hino Malaysia) Engine: 4009cc ...

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Procedure below assumes you’re an experienced tech and have the Hino factory workshop manual to hand for the exact specs (torques, clearances, part numbers) for the specific WU/XZU engine in question. Use this as a step‑by‑step workshop procedure for replacing/servicing valve springs and associated components.

Summary — required tools & consumables
- Basic hand tools: metric sockets/ratchets, extensions, combination wrenches, breaker bar.
- Torque wrench (appropriate range, calibrated).
- Camshaft/rocker marking paint or labels and marker.
- Valve spring compressor — appropriate style for the engine:
- C‑frame screw‑type compressor or lever‑type external compressor for single springs under rocker geometry, OR
- Pushrod/collet style internal compressor if head/cam must stay in place. (Specify model that reaches between cam and retainer for Hino SOHC layouts.)
- Small magnet or keeper pick, small flat screwdriver, snap‑ring pliers (if used).
- Valve stem seal installer (cup) and seal pliers
- Feeler gauges (for valve clearance), feeler gauge set or dial gauge where required.
- Dial caliper or micrometer (check spring free length and installed height).
- Valve spring tester (recommended) or comparator.
- Compressed air source and adapter (optional) to hold valves in closed position through injector or spark plug hole — use only with proper adapters and controlled pressure (workshop manual guidance).
- Engine assembly lube, clean rags, degreaser, gasket sealant if required.
- Replacement parts: valve springs (set), valve stem seals (recommended always replace), retainers (if worn), collets/keepers (replace if worn), possibly valves, valve guides (if worn), head gasket or cam seal gaskets if head/ cam removed. New cam cap bolts/head bolts if they are torque‑to‑yield per manual.
- Personal protective equipment: safety glasses, gloves.

Safety precautions (non‑negotiable)
- Work on a cold engine. Hot engines increase risk of burns and valve spring oil/wear changes.
- Disconnect battery negative.
- Support the vehicle/engine safely if mounts are disturbed.
- Use eye protection — compressed springs/keepers can fly out.
- If using compressed air to hold valves, use a pressure regulator and adapter; do not exceed the manual’s recommended pressure.
- Do not improvise on valve spring tools — improper compressors can slip and cause injury or damage.

Step‑by‑step procedure
1) Preparation and access
- Park on level, engage parking brake, chock wheels, disconnect battery.
- Remove engine covers, air intake ducting, turbo plumbing, as required to access valve cover(s).
- Remove valve cover(s). Label and store bolts in order; mark camshaft/rocker positions so reassembly orientation is preserved.
- Clean work area and degrease surfaces to avoid contamination falling into head.

2) Identify engine configuration and plan
- Determine if the engine is SOHC/DOHC and whether cam removal is required to access springs. On most Hino Dutro diesel OHC engines you can service springs without fully removing the head, but camshaft or rockers may need to be unbolted or swung out—follow the factory procedure.
- Rotate engine to TDC of the cylinder(s) you will work on using crank pulley. Mark timing if cam or timing cover removal is anticipated.

3) Make valve safe (two common methods)
- Method A — Valve spring compressor (preferred when possible):
- Install the valve spring compressor over the retainer/retainer seat. Ensure tool aligns concentrically with the spring retainer.
- Slowly tighten compressor to compress the spring until keepers (collets) are exposed in the retainer groove.
- Remove keepers with a magnet/pick; collect keepers in a dish, keeping top & bottom pairs organized.
- Slowly release compressor, remove retainer and spring.
- Method B — Compressed air to hold valve (alternative; use adapter into injector hole):
- Fit appropriate adapter into injector bore or glow plug/spark plug hole.
- Apply regulated air (per shop manual, typically low psi) to hold the valve seated while you remove the retainer with a spring compressor or with a C‑clamp style compressor used externally.
- This method prevents valve dropping into the cylinder and allows servicing without removing camshaft on some engines.

How to use the valve spring compressor (detail)
- Choose the correct size/adapter cups for the retainer shape.
- For screw‑type compressors: center the upper cup on the retainer and the lower support on the cylinder head or rocker boss. Tighten the screw slowly; keep the tool square. Do not cock the tool — that can bend the spring or retainer.
- For lever‑type compressors: engage the lever and adjust until you feel even pressure. Never use cheater bars to release sudden pressure.
- When keepers are out, back off the compressor slowly. Rapid release can fling retainer or keepers.

4) Inspect parts as you remove
- Inspect each valve spring for cracks and measure free length. Compare to new spring spec. Replace springs that are out of spec or show leg fatigue.
- Inspect retainers and keepers for wear or mushrooming. Replace if any wear.
- Replace valve stem seals whenever you remove the springs — cheap insurance against oil burning.
- Check valve stem tips, guides, and seats for wear. If valves are pitted/burnt, plan valve grinding or replacement.
- If camshaft/caps removed, mark caps and journal order before removal and follow torque sequence on reassembly.

5) Reassembly of springs & seals
- Clean the retainer and spring seats. Lightly oil valve stems with engine oil or assembly lube.
- Fit new valve stem seals using the installer cup — press squarely to seating depth indicated by the manual.
- Install spring onto valve, then retainer.
- Compress spring with the compressor tool until retainer groove is accessible and fit keepers. Ensure keepers seat correctly in the retainer groove — they must sit flush on the retainer. A small dab of grease on keepers helps hold them while you release the compressor.
- Slowly and evenly release compressor, making sure the retainer is seated and keepers remain in place.
- Double‑check that each keeper pair is fully seated around the valve stem grove. Use a magnifier if needed.

6) Setting valve clearance / lash
- If the engine uses adjustable rockers / shims, follow factory procedure for setting lash: rotate engine to TDC for each cylinder and set clearance with feeler gauge to specified clearance at cold/hot as manual requires.
- If the engine uses hydraulic lifters, check for proper lifter preload and priming procedure after reassembly.
- Where applicable, rotate the engine two full turns and re‑check lash/clearance.

7) Reassembly of covers & timing components
- If camshaft/caps were removed, re‑install in original order and torque bolts to the specified sequence & values from the manual.
- Refit valve cover with new gasket or sealant as required. Torque to spec.
- Reconnect any intake/exhaust components removed, sensors, battery.

8) Initial start & checks
- Refill any drained fluids (oil level check, coolant if disturbed).
- Crank engine until oil pressure indicated and ensure oil pressure build‑up to normal range before prolonged idling.
- Start engine, listen for unusual noises. Check for oil leaks at valve cover and cam seals, and check for blow‑by or smoke.
- After a short run (per manual, often after warm‑up), re‑check valve clearances and torque of cam caps if specified.

Replacement parts usually required
- Valve springs (if replacing). Replace as a set or at minimum per cylinder bank if specs exceed wear limits.
- Valve stem seals — recommended every time valve springs removed.
- Keepers/collets and retainers if worn or deformed.
- Camshaft or head gaskets and seals only if those components are removed.
- Head bolts/cam bolts only if they are torque‑to‑yield in the manual.

Common pitfalls & how to avoid them
- Not using the correct compressor: cheap or mis‑sized tools slip and damage retainers or injure hands. Use an engine‑specific compressor or properly sized universal tool.
- Losing or mixing keepers/retainers: mark parts and store them per cylinder. Keepers are matched pairs and must be correctly seated.
- Not replacing valve stem seals: leads to oil consumption/smoke and premature deposit build up.
- Reusing fatigued springs: measurable free length and installed height must be checked; do not assume springs are OK.
- Incorrectly seating keepers: visually inspect seating before removing tool.
- Not following cam timing/marking: if cam removed, improper timing causes valve‑to‑piston contact and catastrophic damage.
- Not torquing cam caps/head bolts in correct sequence: can lead to distortion and oil leaks.
- Overpressurizing cylinder with compressed air: use regulated low pressure and correct adapter to avoid damage.

Final notes
- Always consult the Hino workshop manual for the exact engine model for specifications: valve clearance, torque values, spring installed height, acceptable spring free length, and any special procedures (e.g., shim selection or hydraulic lifter priming).
- If you’re replacing springs as part of a symptom investigation (ticking, misfire, compression loss), perform compression/leak‑down tests and inspect valve seats/guides before final assembly.

End.
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