1. Repair and maintenance of concrete mixer truck

For the safe operation of the vehicle and prolong the service life of the vehicle, please repair and maintain it in a timely manner according to the user manual, and if necessary, contact the customer service department of CIMC Special Vehicles or the local maintenance service station in time.

1. Daily inspection and maintenance

1.1. For the daily inspection and maintenance of the chassis and engine, please refer to the "Instruction Manual" provided by the chassis manufacturer, and strictly follow its requirements. If necessary, go to the chassis manufacturer's service station for repair and maintenance.

1.2. Before starting the concrete mixer truck, a comprehensive inspection must be carried out to check whether the components are normal and reliable, whether the bolt connections are tight, and whether the operation is flexible.

1.3. Whether the hydraulic and pneumatic system pipelines are tightly sealed, whether there is wear, whether there is oil leakage, air leakage, etc. should be checked and eliminated in time.

1.4. After each use, the inside of the mixing drum and the feed hopper, chute, discharge chute, etc. should be cleaned. Before leaving get off work, the whole vehicle, the feeding hopper, the inside and outside of the mixing drum, and the discharge chute must be cleaned. If you find that there is a concrete block in the local area, it should be removed as soon as possible, but the machine parts should not be damaged.

1.5. When maintenance personnel enter the mixing drum for maintenance, the engine must be turned off, and the mixing drum must be locked from rotating to prevent injury to people.

1.6. Contents of daily inspection and maintenance

Serial	Check content	Check cycle	Actions
1	Chassis and Engine	Daily	Check and maintain according to the instructions
2	Is there any loose bolts in each connection part	Daily	Tighten as required
3	Whether there is concrete and dirt in each part	Daily	Clean and repair in time
4	Whether the oil pipes and joints of the hydraulic system leak oil	Daily	Tighten fittings or replace seals
5	Reducer, oil pump and motor for oil leakage	Daily	Replace the seal
6	Is the hydraulic system noise normal?	Daily	If the noise is loud, replace the filter and try again
7	Whether the water pipe is leaking	Daily	Tighten the hoop or replace the hose

2. Regular inspection and maintenance

2.1. For the regular inspection and maintenance of the chassis and engine, please refer to the "Instruction Manual" provided by the chassis manufacturer, and strictly follow its requirements. If necessary, go to the chassis manufacturer's service station for repair and maintenance. New cars must undergo the first mandatory maintenance.

2.2. Regularly check the hydraulic oil tank and reducer oil level.

2.3. Regularly check the wear of the stirring blades and repair them in time.

2.4. Regularly add lubricating oil and grease to all parts.

2.5. Important note: After the first 50 hours of work, use a torque wrench to fasten the connecting bolts everywhere.

2.6. Regularly check the filter element and vacuum gauge of the hydraulic oil tank to prevent the filter element from causing too much resistance to oil return due to poor oil quality.

2.1. Contents of regular inspection and maintenance

Serial	Check content	Check Cycle	Actions
1	Chassis and Engine	As requested	Check and maintain according to the instructions
2	Whether there is excessive wear and damage on the raceway surface	Timely	Appropriately apply a layer of grease
3	With or without concrete blocks in the mixing drum	Monthly	Scrape off
4	Is the discharge chute flexible?	Timely	Add grease in time
5	First hydraulic oil change	500 hours	Oil change and filter
6	Hydraulic system oil change	2000 hours or one year	Oil change and filter
7	First gear oil change	150 hours	Oil change
8	Reducer oil change	2000 hours or one year	Oil change
9	Drive shaft lubrication	Monthly	Add grease
10	Roller lubrication	Timely	Add grease
11	Insufficient reducer oil level	Monthly	Add oil
12	Insufficient hydraulic oil level	Monthly	Add oil
13	The vacuum gauge indicates whether it is in the red area	Monthly	Replace filter
14	Inflexible operating system	Monthly	Add grease
15	Whether the hydraulic hose is aging	2~3 years	Replace the hose

Note: 1. Please use environmentally friendly methods to dispose of discarded hydraulic oil, lubricating oil and grease.

2. The oil spilled around must be wiped off. Leaving it around could contaminate the vehicle and even cause a fire.

1. Maintenance when not in use for a long time

3.1. If the mixer truck is not used for a long time, it should be stored in a ventilated and moisture-proof garage, and should not be stored in the open air. At the same time, the coolant and fuel should be drained, the power supply should be cut off, and the doors and windows should be locked. If it is stored in the open air for a short period of time, it should be covered with canvas, especially at the mouth of the feeding hopper and mixing drum. Otherwise, rainwater will enter the mixing drum and cause a large amount of water accumulation, which will cause indentation between the roller and the raceway of the mixing drum, and make the Corrosion occurs inside the mixer drum.

3.2. Important measures to be launched regularly:

Method	Standard
Start the engine	idling
Drum rotation	1 r/min
time interval	1 month
Runtime	30 min

3.3. If it is not used for a long time, the lubricating grease of the moving parts will dry up, and the rotating parts of the hydraulic drive part will also lose oil, which will cause accidental damage. Check the entire lubrication system before each start, and add oil or replace if necessary.

3.4. If it is not used for a long time, it is necessary to carry out a maintenance of the whole vehicle, and to protect the surface of the feeding hopper, discharge chute and mixing drum to prevent corrosion.

3.5. For the deactivation and maintenance of the chassis, please refer to the requirements of the "Instruction Manual" of the chassis.

2. Rules for the use of oil products

4.1. Requirements for oil products:

Anti-wear hydraulic oil: Cleanliness: ISO 18/13 Viscosity: ISO VG 46 & ISO VG 68

Gear Oil: Grade API GL 5 Grade: SAE 80W/90 or SAE 85W/140

Grease: No. 2 lithium base grease

project	Capacity (l)	grade	Viscosity vs Ambient Temperature
project	Capacity (l)	grade	-10℃/+30℃	+20℃/+45℃
Hydraulic oil	27	ISO 18/13	ISO VG 46	ISO VG 68
reducer oil	11.5	API GL 5	SAE 80W-90	SAE 85W-140
Oil for ZF PLM9	21.5	-API CD/CE/CF/SF/SG	SAE 10W-40	SAE 15W-40

Note: The hydraulic oil filled in CIMC mixer truck is AW68, the gear oil of reducer is 85W-90, and the oil of ZF integral reducer is SAE 15W-40.

4.1. Different brands of hydraulic oil cannot be mixed. When replacing the hydraulic oil, the original hydraulic oil in the tank must be completely drained before adding new hydraulic oil.

4.2. Gear oils of different brands cannot be mixed. When replacing gear oil, the original gear oil in the reducer must be completely drained before adding new gear oil.

4.3. Hydraulic oil change cycle: 500 working hours for the first time, and every 2000 working hours or one year thereafter.

4.4. Reducer oil change cycle: 150 working hours for the first time, and every 2000 working hours or one year thereafter.

4.5. When the user replaces the oil of another brand, the oil of the same grade must be used.

4.6. When changing the oil, it must be ensured that no impurities enter the system.

2. Common faults and maintenance

Common faults			Cause of failure	Exclusion method
Empty car can be turned, but not after loading			Dirty hydraulic oil	Clean the hydraulic oil tank and replace the hydraulic oil
			Insufficient oil	Additional
			Internal wear of oil pump motor	Overhaul after disassembly, replace worn parts
Only unilateral rotation			The servo mechanism is not working well	Replace or Repair
Only unilateral rotation			One-sided failure of high pressure relief valve	Replace or Repair
Joystick is in stop position and still turning			The joystick center position adjustment is not good	Rescale
			Servo regulator not tuned	Rescale
			The leakage of the pump is too large	Repair or Replace
Mixing drum pulsating rotation			The servo regulator does not work well	Repair or Replace
Mixing drum pulsating rotation			Joystick loose	Rescale
The mixing drum cannot be rotated	Abnormal control mechanism		Dislodged or damaged	Reinstall or adjust as normal
	The servo mechanism cannot be moved by hand		Servo failure	Replace servo valve or disassemble for repair
	The boost pressure is normal		High pressure relief valve failure	Replace high pressure relief valve or disassemble for repair
			Motor damaged	Replace motor
			Reducer damage	Replace the reducer or disassemble it for repair
	Boost pressure lower than standard value		Failure of booster pump	Replace hydraulic pump
			Failure of boost relief valve	Replace boost relief valve or disassemble for repair
			Damage of hydraulic pump	Replace hydraulic pump
	Insufficient hydraulic pump pressure		Dirty or insufficient hydraulic oil	Clean hydraulic tank , replace or replenish hydraulic oil
			Internal leakage in manual servo valve	Replace the seal
			The orifice is blocked	Cleaning
			Internal leakage of hydraulic motor	Replace the seal or motor
	Abnormal hydraulic pipeline		Hydraulic line damage	Replace hydraulic lines
Slow speed of mixing drum			Dirty hydraulic oil, insufficient oil absorption	Clean or replace hydraulic tank suction filter
			Oil leakage in hydraulic system	Repair or replace gasket or apply sealant
			Control mechanism stuck	Overhaul
The mixing drum rotates without material			Severe water loss of concrete	Add appropriate amount of water, and then discharge after stirring
The mixing drum rotates without material			Severe blade wear	Repair or Replace
Noise		Pump suction	Oil suction filter clogged	Change filter
		Oil Foam	Insufficient oil	Additional
		Oil Foam	Air filter clogged	Clean or replace
		The amount of oil is too high	Continuous time too long	Shutdown cooling
		The hydraulic motor is noisy	There are debris such as iron filings in the motor	Cleaning or overhauling
		Noise in hydraulic pump	There are debris such as iron filings in the hydraulic pump	Cleaning or overhauling
		Noise in the reducer	Too much debris in the reducer	Change gear oil, clean or overhaul
		Noise in the reducer	Heavily worn	Overhaul
Inflexible Manipulator			The joystick is seriously deformed	Correction, adjust screw
Inflexible Manipulator			Rust or concrete stuck	Remove rust and concrete, add butter
The mixing tank jumps up and down			Uneven wear of raceways and idlers	Repair or Replace
			Worn or damaged roller bearings	Replace bearing
			The idler nut is loose	Relock
Reducer seepage (leak) oil			Damaged seal	Replace the seal
Oil seepage at the junction of motor and reducer			Damaged seal	Replace the seal
Joystick Heavy			Rust control mechanism span>	Derusting, Grease, Replace
Joystick Heavy			Servo valve control force is heavy	Replace
Hopper clogged			The feeding is not evenly stirred, and the feeding is too fast	Use tools to pound through the blockage to control the discharge speed
Hopper funnel			The rubber ring of the hopper is worn out	Replace with a suitable size rubber sheet
Concrete discharge is not smooth			Adhesion in the mixing drum	Remove Adhered Concrete
Concrete discharge is not smooth			Concrete water loss	Add appropriate amount of water, and then discharge after stirring
Segregation of concrete			The rated speed of the mixer is low	Appropriately increase the speed
			Insufficient agitation before discharge	Agitate before discharge
			Severe blade wear	Replace the blade

3. Common faults and countermeasures of each component

Part	Common malfunctions	Failure analysis	Troubleshooting
Pump and horse up to	The shaft of the motor does not rotate (no power transmission)	Is the input shaft of the oil pump rotating? Make sure the drive shaft is connected	Connect the drive shaft
		No oil in the tank	Fill up the hydraulic oil to the upper limit of the oil level
		Vacuum gauge indicates abnormal	It is easy to cause vacuum at low temperature, so it is necessary to carry out when driving a cold car.10～20minutes of warm-up operation.
		Vacuum gauge indicates abnormal	Replace the filter element
		The inlet of the charge pump is oil-free.	Loosen the connection at the charge pump inlet to confirm that there is no oil passing through.
		Oil charge pressure is abnormal	Replacement product or part
		The above confirmation results are normal. If the motor still does not rotate, there is a problem inside the oil pump.	Replacement product or part
	The motor does not reach the specified torque (with power transmission)	System has pressure but no RPM	Replacement product or part
		The speed is there but the system pressure is not	Insufficient motor torque to replace products or parts
		High pressure in the low pressure line	Replacement product or part
	The motor only rotates in one direction	The external connection structure of the control valve is not suitable	Adjustment
		The neutral position of the control valve is not suitable	Replacement product or part
		The high pressure relief valve has a bad direction	Replace components
		Shuttle spool stuck in one direction	Replacing the Manifold Assembly
		One-way valve one-way failure	replace
		Defective servo piston	replacement product
	The neutral position of the lever has been changed	1There is a difference between the neutral position of the external controller and the joystick.	Adjustment
		The lever can be turned lightly without resistance	Replacing components or performing supplemental installations
		Lever does not return to neutral position	Replace components
		The control relationship of the servo cylinder is normal but cannot enter the neutral position	Replace pump or components
	Oil temperature is too high	Insufficient fuel in the tank	Add the same brand of hydraulic oil to the neutral position
		There is dirt accumulation in the cooler and the outside is blocked	clean up
		Filter is clogged	Replace the filter element
		Suction pipe is seriously deformed	Correct or replace the oil suction pipe
		The high pressure relief valve is always open	Replace components
	Pump and motor noise	Insufficient fuel in the tank	Fill up the hydraulic oil to the upper limit of the oil level
		The suction pipe joint is loose	Tighten the joint
		Welding of oil pump bracket	Repair welding
		Motor connecting bolts loose	tighten
		Internal damage of oil pump and motor	Replace the oil pump motor or supplement
		Relief valve interference of oil pump and motor	Replace or adjust relief valve
		Low-speed rotation (below 600rpm) is very noisy	Product replacement
	Insufficient acceleration and deceleration	Insufficient hydraulic oil or changes in oil quality	Replace or top up hydraulic oil to the upper limit of the oil level
		Insufficient charge pressure	Replacement of products or parts
		Bad control valve	Replacement of products or parts
		Low engine input speed	Negotiate with engine manufacturers
	Oil leaking from oil seal	There is an abnormally high pressure in the oil pump motor housing	fix
	Oil leaking from oil seal	Damage to mechanical seal and oil seal	Replace the seal assembly
	Metal dust load in oil	Abnormal noise of oil pump and motor	Replace oil pump and motor components
		Metal powder in the fuel tank and filter	Replace oil pump and motor components
		add dirty oil	Replace oil pump and motor components
Reducer	Box overheating	Insufficient lubricating oil	Top up the gear oil to the upper limit of the oil level
	Oil smells bad	Deterioration of lubricating oil	Change gear oil
	Internal noise of reducer	Insufficient lubricating oil	replace
	Internal noise of reducer	Internal damage	Replacing the reducer or component
	oil spill	Oil seal damage	replace
	oil spill	Loose plugs and bolts	tighten
Fuel tank radiator	oil spill	loose joint	tighten
		box crack	Repair welding or replacement
		Add too much hydraulic oil	Adjust the hydraulic oil to the upper limit of the oil level
	Fan does not turn	The oil temperature does not exceed the lower limit of the temperature control switch.
		The temperature control switch fails	replace
		Damaged fan motor	replace or repair
		The power cord is disconnected	turn on
	fan reverse	Power cord reversed	correct
High-pressure pipeline	Oil leakage from joint	loose joint	tighten
		O Ring damage	replace
		The joint is not fastened firmly	Replace the oil pipe
	oil pipe burst	System pressure too high	Adjust system pressure, replace parts or components
	oil pipe burst	Oil pipe is damaged	Replace the oil pipe