Kubota D850 Engine
The Kubota D850 is a 3-cylinder, liquid-cooled diesel engine widely used in agricultural and public works applications, particularly in Kubota micro-tractors. This compact and efficient engine is known for its reliability and performance in various equipment.
The D850 engine is part of Kubota’s D-series, which includes other models like the D750 and D950. It is designed to provide consistent power output for tasks such as tilling, mowing, and light construction work. The engine’s specifications may vary slightly depending on the specific application, but it generally produces around 14-15 horsepower.
Kubota engines, including the D850, are recognized for their durability and longevity. They are built with high-quality components and feature a robust design that can withstand demanding work conditions. The liquid cooling system helps maintain optimal operating temperatures, contributing to the engine’s overall reliability and performance.
One of the advantages of the D850 engine is its fuel efficiency. Kubota has engineered this model to deliver power while minimizing fuel consumption, making it an economical choice for operators. The engine also complies with relevant emissions standards, ensuring it meets environmental regulations.
Maintenance of the D850 engine is generally straightforward, with easy access to key components for routine servicing. This helps reduce downtime and keeps operating costs in check. Replacement parts for the D850 are readily available through Kubota’s extensive dealer network and aftermarket suppliers.
In some applications, the D850 engine may be paired with Kubota’s innovative Micro-Hybrid system. This technology incorporates a 48V lithium-ion battery and a DC-DC converter to provide instantaneous power assistance during peak load demands. The Micro-Hybrid system can enhance the engine’s performance and efficiency in certain operating conditions.
The Kubota D850 engine continues to be a popular choice for various compact equipment applications due to its combination of power, reliability, and efficiency. Its versatility and proven track record make it a trusted option for both agricultural and industrial uses.
Kubota D850 Specs
The Kubota D850 is a 3-cylinder, liquid-cooled diesel engine commonly used in agricultural and industrial applications. Here are the key specifications of the Kubota D850 engine:
Engine Type: 3-cylinder, 4-stroke diesel engine
Cooling System: Liquid-cooled
Displacement: 855 cc
Bore: 72 mm
Stroke: 70 mm
Horsepower: Approximately 20 HP at 3000 rpm
Torque: Around 50.6 N·m at 1800 rpm
The D850 engine is designed for use in various Kubota equipment, including:
– Micro-tractors like the B1550, B1500, and B6200 models
– Rice harvesters
– Other agricultural and construction machinery
There are two main variants of the D850 engine:
1. Thermosiphon model: This version produces around 18 HP and relies on natural circulation for cooling.
2. Water pump model: This variant generates slightly more power, typically in the 20 HP range, and uses a water pump for more efficient cooling.
The engine features a compact design, making it suitable for use in smaller equipment. It’s known for its reliability, fuel efficiency, and durability in demanding work conditions. The D850 complies with relevant emissions standards, ensuring it meets environmental regulations for its class of engines.
Maintenance for the D850 is generally straightforward, with good accessibility to key components for routine servicing. This helps minimize downtime and keeps operating costs manageable for equipment owners.
Kubota D850 Parts
The Kubota D850 is a 3-cylinder, liquid-cooled diesel engine with a displacement of 855 cc. It has a bore of 72 mm and a stroke of 70 mm. Common parts for this engine include:
Cylinder head components:
– Head gasket set
– Cylinder head gasket
– Rocker cover gasket
– Valve stem seals
– Exhaust manifold gasket
Engine block components:
– Main bearings
– Connecting rod bearings
– Thrust washers
– Piston rings
– Cylinder liners
– Front and rear crankshaft oil seals
Cooling system parts:
– Water pump
– Water pump gasket
– Thermostat
– Thermostat gasket
– Radiator cap
– By-pass hose
Other components:
– Complete gasket set
– Crankshaft
– Connecting rods
– Fuel injection pump
– Fuel injectors
– Glow plugs
– Starter motor
– Alternator
The D850 engine was used in various Kubota equipment, including:
– B1400, B1402, B1500, B1502, B1550, and B6200 tractors
– Rice harvesters
There are two main variants of the D850:
1. Thermosiphon model producing around 18 HP
2. Water pump model producing around 20 HP
The engine is known for its reliability and durability. Replacement parts are generally readily available through Kubota dealers and aftermarket suppliers. When servicing or rebuilding a D850 engine, it’s important to use high-quality parts and follow proper torque specifications for critical components like cylinder head bolts and main bearing caps.
Kubota D850 Applications
The Kubota D850 engine is widely used in various agricultural and industrial applications. It can be found in the following equipment:
Kubota Tractors:
– B1400
– B1402
– B1500
– B1502
– B1550
– B6200
Kubota B1 Series (Bulltra):
– B1-14
– B1-15
Kubota B Series (Zen-Noh):
– ZB1400
– ZB1402
– ZB1500
– ZB1502
Other Applications:
– Rice harvesters
– Small construction equipment
– Generator sets
– Pump sets
– Forklifts
– Compact utility vehicles
The D850 engine is particularly popular in micro-tractors and compact agricultural machinery due to its small size, reliability, and fuel efficiency. It’s often used in equipment designed for tasks like tilling, mowing, and light construction work.
There are two main variants of the D850 engine:
1. Thermosiphon model: This version produces around 18 horsepower and relies on natural circulation for cooling.
2. Water pump model: This variant generates slightly more power, typically in the 20 horsepower range, and uses a water pump for more efficient cooling.
The engine’s versatility and durability make it suitable for a wide range of applications where compact size and reliable performance are required. Its use in rice harvesters from Japan is notable, as these engines often have low hours due to seasonal use, making them popular for repurposing in other equipment.
Kubota D850 Engine for Sale
The Kubota D850 engine is a 3-cylinder, liquid-cooled diesel engine with a displacement of 855 cc. It produces around 20 horsepower at 3000 rpm and 50.6 N·m of torque at 1800 rpm. This engine is commonly used in Kubota micro-tractors and other agricultural equipment.
When looking for a Kubota D850 engine for sale, you may find both new and used options available. Used engines often come from rice harvesters in Japan, which typically have low hours due to seasonal use. These engines are generally well-tested before being offered for sale.
The D850 engine is compatible with several Kubota tractor models, including:
– B1400, B1402
– B1500, B1502
– B1550
– B6200
It’s also used in some Zen-Noh branded tractors like the ZB1400, ZB1402, ZB1500, and ZB1502.
When purchasing a used D850 engine, it’s important to note that there may be some differences compared to your original engine. Components like the crankcase, oil pump, distribution, and intake/exhaust manifolds may vary depending on the original application. You may need to transfer some parts from your old engine.
Prices for Kubota D850 engines can vary widely depending on condition, hours, and whether they are new or used. It’s advisable to request detailed information about the engine’s history, maintenance records, and any recent repairs or rebuilds.
When buying, consider factors like:
– Engine hours
– Overall condition
– Compression test results
– Availability of service records
– Warranty offered (if any)
– Compatibility with your specific equipment
It’s also worth noting that there are two main variants of the D850: a thermosiphon model producing around 18 HP, and a water pump model producing about 20 HP. Ensure you’re getting the correct version for your needs.
Remember to verify the seller’s reputation and ask for detailed photos or videos of the engine before making a purchase. If possible, arrange for an in-person inspection or have a qualified mechanic evaluate the engine before buying.
Kubota D850 Water Pump
The Kubota D850 water pump is a crucial component of the engine’s cooling system. It circulates coolant between the radiator and engine to maintain optimal operating temperatures.
Key details about the Kubota D850 water pump:
– Compatible with Kubota D750, D850, and D950 engines
– Used in various Kubota tractor models including B1400, B1500, B1550, B1600, B1702, and B7100 series
– Typical part numbers include 15534-73030 and 15852-73030
– Driven by a V-belt connected to the engine crankshaft
– Features a pulley that also drives the radiator fan
– Made of durable materials to withstand high temperatures and constant use
Common issues that can affect water pump performance include:
– Bearing seizure due to high rotational speeds
– Damage from improperly balanced pulleys or fans
– Problems caused by belts that are too tight, too loose, worn out, or installed at the wrong angle
– Insufficient lubrication or lack of grease
Signs of water pump failure may include:
– Unusual noises from the engine area
– Coolant leaks or stains under the tractor
– Sudden temperature spikes on the instrument panel
When replacing the water pump, it’s important to ensure proper installation and use high-quality replacement parts. Regular maintenance and inspection of the cooling system can help prevent premature water pump failure and extend the life of the engine.
Kubota D850 Rebuild Kit
A Kubota D850 rebuild kit typically includes the following components:
Engine gasket set (complete)
Piston rings
Main bearings
Rod bearings
Thrust washers
Front and rear crankshaft oil seals
Valve stem seals
Cylinder liners (if applicable)
Pistons and connecting rods (may be optional)
Some kits may also include:
Water pump
Oil pump
Thermostat
Fuel injectors
Glow plugs
The D850 is a 3-cylinder diesel engine with a displacement of 855 cc. It has a bore of 72 mm and a stroke of 70 mm. When rebuilding this engine, it’s important to check the cylinder bores for wear and determine if they need to be re-bored or if cylinder liners need to be replaced.
Key considerations when rebuilding a D850 engine:
– Inspect the crankshaft for wear and straightness
– Check valve seats and guides for wear
– Examine the camshaft lobes and bearings
– Assess the condition of the cylinder head, looking for cracks or warpage
– Replace all bearings, seals, and gaskets
– Use proper torque specifications when reassembling
It’s recommended to have the cylinder head professionally reconditioned, including valve job and surface milling if necessary. The engine block should be thoroughly cleaned and inspected for cracks before rebuilding.
When purchasing a rebuild kit, ensure it’s compatible with your specific D850 engine variant, as there may be slight differences between models. Some kits are available with standard or oversized parts to accommodate worn engine components.
Proper assembly and initial break-in procedures are crucial for the longevity of the rebuilt engine. Follow manufacturer guidelines for assembly tolerances and lubrication during the rebuild process.
Kubota D850 Parts Manual
The Kubota D850 engine parts manual contains detailed information on the components and assembly of this 3-cylinder diesel engine. Key sections typically include:
- Electrical System: Starter motor, alternator, glow plugs, and wiring.
- Engine Specifications: Displacement, bore, stroke, compression ratio, horsepower, torque, and other technical data.
- Cylinder Block Group: Crankshaft, main bearings, connecting rods, pistons, piston rings, cylinder liners, and related components.
- Cylinder Head Group: Valves, valve springs, rocker arms, camshaft, push rods, and associated parts.
- Lubrication System: Oil pump, oil filter, oil pan, and oil passages.
- Cooling System: Water pump, thermostat, radiator, fan, and coolant flow.
- Fuel System: Fuel injection pump, fuel injectors, fuel lines, and filters.
The manual provides exploded view diagrams, part numbers, torque specifications, and assembly instructions for each component group. It also includes maintenance schedules, troubleshooting guides, and adjustment procedures for items like valve clearances and injection timing.
For the D850 specifically, the manual covers variations used in different Kubota equipment, including B-series tractors (B1400, B1500, B1550, B6200), Bulltra models (B1-14, B1-15), and Zen-Noh branded tractors (ZB1400, ZB1500).
When servicing a D850 engine, it’s important to reference the correct manual for your specific engine variant, as there may be slight differences in components or specifications between models. The manual is an essential resource for proper maintenance, repair, and rebuilding of the Kubota D850 engine.
Kubota D850 Oil Capacity
The Kubota D850 engine has an oil capacity of 4.6 liters (4.86 US quarts or 4.05 Imperial quarts). This 3-cylinder diesel engine requires SAE 10W-30 or 10W-40 engine oil meeting CC grade or higher specifications.
When changing the oil, it’s important to replace the oil filter as well. The recommended oil change interval is typically around 200 hours of operation or annually, whichever comes first.
However, for engines used infrequently or in standby applications, changing the oil at least once per year is advisable, even if the hour limit hasn’t been reached.
Regular oil changes are crucial for maintaining the engine’s performance and longevity, especially in small diesel engines where oil can become contaminated more quickly due to the nature of diesel combustion.
Kubota D850 Oil Filter
The Kubota D850 engine uses an oil filter that is compatible with several other Kubota engine models. The filter is typically 100mm in length and fits engines like the D750, D850, D905, D950, D1005, D1105, D1305, V1305, V1505, and V1505T.
For smaller Kubota engines, including the D722, D902, and Z482, an 80mm oil filter is used instead.
When selecting an oil filter for the D850, it’s important to ensure you get the correct size. The part numbers for the 100mm filter often include 15534-73030 or 15852-73030.
Regular oil and filter changes are crucial for maintaining the D850 engine. The recommended interval is typically around 200 hours of operation or annually, whichever comes first. However, for engines used infrequently or in standby applications, changing the oil at least once per year is advisable, even if the hour limit hasn’t been reached.
When changing the oil filter, it’s good practice to also replace the engine oil. The D850 uses SAE 10W-30 or 10W-40 engine oil meeting CC grade or higher specifications. Always refer to your engine’s manual for the most accurate information regarding oil and filter specifications and change intervals.
Kubota D850 Temperature Sensor
The Kubota D850 engine typically uses a temperature sensor to monitor coolant temperature and provide data to the engine control system. This sensor is usually located on the engine block or cylinder head where it can accurately measure the coolant temperature.
Key details about the D850 temperature sensor:
– It is typically a thermistor-type sensor that changes resistance as temperature changes
– The sensor connects to the engine control unit (ECU) or temperature gauge
– It helps regulate engine temperature by triggering the cooling fan and providing data for fuel injection timing
– Common locations include the thermostat housing or water outlet
– The normal operating temperature range is typically between 180-200°F (82-93°C)
– Sensor failure can cause overheating issues or inaccurate temperature readings
When replacing the temperature sensor on a D850 engine, it’s important to use the correct part number specified for that engine model. Improper sensor selection or installation can lead to inaccurate temperature readings and potential engine damage.
Common symptoms of a failing temperature sensor include:
– Erratic or stuck temperature gauge readings
– Check engine light illumination
– Poor fuel economy
– Engine running too hot or too cold
– Rough idling or stalling
Regular inspection of the temperature sensor and its wiring is recommended as part of routine maintenance to ensure proper engine temperature monitoring and control. If issues are suspected, diagnostic testing of the sensor’s resistance at different temperatures can help determine if replacement is needed.
Kubota D850 Generator
The Kubota D850 engine can be equipped with a generator system for electrical power production. The generator for this engine typically has the following specifications:
Voltage: 12V
Power output: Approximately 14 amps
Mounting: 2-hole design
The generator is compatible with several Kubota engine models including the D722, D850, and D950. It often comes with an integrated voltage regulator.
Common part numbers for the D850 generator include:
1553164011
1553164012
1553164013
1553164014
1553164015
1553164016
1553164017
This generator is used in various Kubota equipment applications such as:
Compact tractors (e.g. B1550D)
Commercial mowers
Excavators
Front mowers (e.g. F2000)
Garden tractors
When replacing the generator, it’s important to ensure compatibility with your specific D850 engine variant. The generator is typically driven by a V-belt connected to the engine crankshaft pulley.
Regular maintenance of the charging system, including checking belt tension and inspecting electrical connections, helps ensure proper generator function. If you experience issues with battery charging or electrical system performance, the generator may need testing or replacement.
For optimal performance and longevity, it’s recommended to use OEM or high-quality aftermarket generators designed specifically for the Kubota D850 engine.
Kubota D850 Thermostat
The Kubota D850 engine uses a thermostat to regulate coolant temperature and maintain optimal operating conditions. The thermostat for this engine typically has the following characteristics:
Flange size: 38mm
Opening temperature: Around 71°C (160°F)
Fully open temperature: Approximately 85°C (185°F)
This thermostat is compatible with several other Kubota engine models, including the D600, D650, D662, D722, D750, D782, D950, V1100, and V1200 series engines. It’s also used in some Z-series engines like the Z400, Z402, Z482, Z500, Z600, and Z620.
The thermostat is usually located in the thermostat housing, which is positioned between the engine block and the upper radiator hose. Its primary function is to control the flow of coolant, keeping it within the engine until it reaches the optimal operating temperature.
When replacing the thermostat, it’s important to also replace the thermostat gasket to ensure a proper seal and prevent coolant leaks. Some common signs of a failing thermostat include:
1. Engine overheating or running too cool
2. Fluctuating temperature gauge readings
3. Coolant leaks around the thermostat housing
4. Poor fuel economy
Regular inspection and replacement of the thermostat as part of routine maintenance can help ensure proper engine temperature regulation and prevent potential overheating issues. When installing a new thermostat, make sure to orient it correctly and bleed the cooling system of any air to ensure proper operation.
Kubota D850 Starter
The Kubota D850 starter is a 12-volt electric starter motor designed for use with the Kubota D850 diesel engine. This starter is compatible with several other Kubota engine models as well, including the D950 and V1305.
Key specifications for the Kubota D850 starter include:
Voltage: 12V
Power output: Approximately 0.9 kW
Number of teeth on drive gear: 8
Rotation: Clockwise when viewed from drive end
The starter motor is designed to crank the engine during the starting process. It engages with the engine’s flywheel to turn the crankshaft and initiate combustion. Once the engine starts, the starter automatically disengages.
This starter is used in various Kubota equipment, including:
Tractors: B1700 series, B2100 series, B2400 series, B7500 series
Excavators: KH35, KH41
Other applications: Compact utility vehicles, generator sets, and pump sets
When replacing the starter on a Kubota D850 engine, it’s important to ensure compatibility with your specific equipment model. Some common part numbers for this starter include:
15504-63010
15504-63012
16285-63011
1547163011
The Kubota D850 starter is known for its reliability and durability. However, like all mechanical components, it may eventually require replacement due to wear or failure. Common signs of a failing starter include:
– Slow cranking
– Clicking sound when trying to start the engine
– Engine fails to turn over
– Intermittent starting issues
Regular maintenance of the electrical system, including checking and cleaning battery connections, can help prolong the life of the starter motor. When installing a new starter, it’s advisable to also inspect and potentially replace related components such as the starter solenoid and battery cables if they show signs of wear.
Replacing Starter Motor
To replace the starter motor on a Kubota D850 engine, follow these general steps:
1. Disconnect the negative battery cable for safety.
2. Locate the starter motor, typically mounted on the side or bottom of the engine.
3. Disconnect the electrical connections to the starter:
– Remove the main power cable from the starter solenoid
– Unplug the starter solenoid connector
4. Remove the mounting bolts that secure the starter to the engine block. There are usually two bolts.
5. Carefully remove the old starter motor from the engine. It may be heavy, so support it as you remove it.
6. Compare the new starter to the old one to ensure it’s the correct replacement.
7. Install the new starter motor:
– Position it in place on the engine
– Insert and tighten the mounting bolts
8. Reconnect the electrical connections:
– Attach the main power cable to the starter solenoid
– Plug in the starter solenoid connector
9. When tightening the main power cable nut on the solenoid, use a torque wrench set to 6.5 foot-pounds. Over-tightening can damage the solenoid contacts.
10. Reconnect the negative battery cable.
11. Test the new starter by starting the engine.
Remember to consult your specific Kubota D850 service manual for precise torque specifications and any model-specific instructions. Proper installation is crucial for the starter’s performance and longevity.