1. Always check the tension of the saw chain. When checking and adjusting, please turn off the engine and wear protective gloves. The proper tension is that when the chain is hanging on the lower part of the guide plate, the chain can be pulled by hand. 2. There must always be a little oil spilled on the chain. Every time before work, the chain lubrication and the oil level of the lubricant tank must be checked. The chain can't work without lubrication. If working with a dry chain, the cutting device will be damaged. 3. Never use old motor oil. The old engine oil can not meet the lubrication requirements and is not suitable for chain lubrication. 4. If the oil level in the oil tank does not decrease, there may be a problem with the lubrication and delivery. Should check the chain lubrication, check the oil circuit. Passing the contaminated filter can also lead to poor lubricant supply. The lubricating oil filter in the connecting pipe between the oil tank and the pump should be cleaned or replaced. 5. After replacing and installing a new chain, the saw chain needs 2 to 3 minutes of running-in time. Check the chain tension after running in and readjust if necessary. New chains require more frequent tensioning than chains that have been used for a while. The saw chain must be attached to the lower part of the guide plate when it is cold, but the saw chain can be moved on the upper guide plate by hand. If necessary, tighten the chain again. When the operating temperature is reached, the saw chain expands slightly and sags, and the drive joint at the lower part of the guide plate cannot be taken out of the chain groove, otherwise the chain will jump, and the chain needs to be retensioned. 6. The chain must be relaxed after work. The chain shrinks as it cools, and a chain that does not loosen can damage the crankshaft and bearings. If the chain is tensioned under working conditions, the chain will shrink during cooling, and over-tightening the chain will damage the crankshaft and bearings. 1/4" pitch saw chains