Kawasaki agent sharing: Examples of Hitachi excavator parts troubleshooting and repair.

2025-06-26

The excavator brands and varieties in the hands of excavator friends are complex, and different excavator parts have different reactions to problems and repair methods. So Kawasaki's agent editor has been trying their best to clean up the repair plans for various brands of excavator parts problems for us to refer to and learn from. Today, let's first introduce the repair examples of Hitachi excavators.

Problem 1: Hitachi 70 excavator water tank lacks water and emits white smoke

Disadvantage phenomenon:

The Hitachi 70 excavator underwent a major overhaul due to a rollover, and after being repaired and used for 2-3 hundred hours, the excavator's water tank became short of water after a few days, with high exhaust and white smoke.

Repair plan:

1. After the overhaul of the excavator engine, there was a water shortage and white smoke in the water tank. It is recommended to first check whether the diesel used by the excavator is mixed with water.

2. The Hitachi 70 excavator mentioned above uses oil from Sinopec, and the oil-water separator for excavator accessories is often inspected, so this drawback needs to be addressed.

3. Then add water to the water tank to the standard position according to the rules, and start the excavator to check if there are bubbles in the auxiliary water tank of the excavator.

4. Assuming there are bubbles, it indicates that the engine cylinder gasket has split, resulting in the Hitachi 70 excavator water tank being short of water and emitting white smoke.

Assuming there are no bubbles, check if there are cracks in the cylinder head of the Hitachi 70 excavator. If there are, replace the excavator parts with new ones.

Analyze the reasons for the shortcomings:

1. There is water in the diesel fuel.

2. The water tank cylinder gasket punching machine or the cylinder gasket is damaged.

3. Initiate cracks in the engine water tank cover.

Disadvantage 2: Vibration of Hitachi 120-5 engine

Phenomenon of malfunction:

The engine of the Hitachi 120-5 excavator vibrates after starting, and it vibrates in any movement. When the excavator is digging, it feels like the engine is about to shut down, and the excavator cannot work normally.

Reason for the malfunction:

1. The foot screw of the excavator accessory is loose.

2. The engine floor mat is loose.

3. The engine floor mat is damaged.

4. If the engine foot pad lock is too tight, the engine will also vibrate.

5. There is a problem with the crankshaft bearings.

6. The engine oil of the excavator is not working properly.

7. The adjustment of the high-pressure oil pump supply for excavator accessories is inconsistent.

8. The screw filter of the hand oil pump is blocked.

9. One cylinder of the engine is not working.

10. The plunger spring of the diesel pump is broken.

Repair plan:

1. Firstly, check if the engine floor mat is too loose or too tight, and if the floor mat is worn out.

2. Then check if the oil added to the diesel pump of the excavator parts is not working properly? Is the engine oil too dirty.

3. Then increase the engine throttle and listen for any abnormal noise from the engine.

4. No abnormal noise, check if the oil supply of the excavator's high-pressure oil pump is too small or too large.

5. Finally, conduct a cylinder breakage test to determine if one cylinder of the engine is malfunctioning, and check if the diesel pump plunger spring of the excavator accessory is broken.

Problem 3: There is engine oil in the water tank of Hitachi ZAX70 excavator

Phenomenon of malfunction:

After using the Hitachi ZAX70 excavator for more than 4000 hours, it was found that there was engine oil in the excavator water tank.

Analyze the cause of the problem:

1. First, check if the excavator oil cooling core has broken.

2. After checking, it was found that there was no rupture. Then, we checked the water pump of the excavator parts to see if the water seal of the water pump was worn and if the drainage hole of the water pump was blocked.

3. The water seal is not worn and the drainage hole is not blocked, so it is impossible to check if the cylinder gasket of the excavator water tank is a punch press.

4. If the cylinder gasket of the water tank is damaged, it may cause oil problems in the excavator's water tank.

That's all for today's introduction of repair examples for Hitachi excavator parts. I believe that excavator friends with Hitachi excavators will have a harvest! Next, Kawasaki agent editor will also collect examples from other brands. Stay tuned!

The above is the Kawasaki agent knowledge sharing compiled by Kunshan Chuanna Hydraulic Parts Co., Ltd.: Hitachi excavator parts fault repair examples. If you want to purchase Kawasaki parts, please contact us by phone or consult online!