Page 2 - SPECIFICATIONS; Symbol; Intended use
2 ENGLISH (Original instructions) SPECIFICATIONS Model UC3050A UC3051A UC3550A UC3551A UC4050A UC4051A UC4550A UC4551A Max. chain speed 14.5 m/s (880 m/min) Bar length 300 mm 350 mm 400 mm 450 mm Cutting length 260 mm 320 mm 355 mm 415 mm Standard guide bar Guide bar type Sprocket nose bar Type 91PX...
Page 4 - Chain saw safety warnings; Do not operate a chain saw in a tree.
4 tool’s operation. If damaged, have the power tool repaired before use. Many accidents are caused by poorly maintained power tools. 23. Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are less likely to bind and are easier to control. 24. Use the power...
Page 5 - ADDITIONAL SAFETY RULES; Proper use; not; Personal protective equipment
5 014316 − Do not overreach and do not cut above shoulder height. This helps prevent unintended tip contact and enables better control of the chain saw in unexpected situations. − Only use replacement bars and chains specified by the manufacturer. Incorrect replacement bars and chains may cause chai...
Page 6 - a risk of explosion.; Kickback
6 using the saw in the open air, ensure that the cable employed is intended for open-air use and is rated accordingly. 3. Keep the cord away from the cutting area and to position cord so that it will not be caught on branches, and the like, during cutting. 4. Do not operate the chain saw in the vici...
Page 7 - Safety features; front and rear hand guards; Transport and storage; If any of these symptoms occur, see a physician!; SAVE THESE INSTRUCTIONS.
7 Safety features 1. Always check that the safety features are in working order before starting work. Do not use the chain saw if the safety features are not working properly. − Chain brake: The chain saw is fitted with a chain brake which brings the saw chain to a standstill within a fraction of a ...
Page 8 - DESIGNATION OF PARTS
8 DESIGNATION OF PARTS (Nut model: the sprocket cover is tightened by nuts.) For Model UC3050A, UC3550A, UC4050A, UC4550A 1 2 3 4 5 6 9 10 8 014372 (Lever model: the sprocket cover is tightened by lever.) For Model UC3051A, UC3551A, UC4051A, UC4551A 1 2 3 4 5 6 9 10 8 7 014373
Page 9 - ASSEMBLY; Removing or installing sprocket cover
9 (For all models) 14 12 11 15 13 17 16 18 014514 Cord hook 1 2 3 4 5 6 7 9 8 10 11 12 13 Spike bumper 18 14 15 16 17 Rear handle Switch trigger Oil filler cap Front handle Front hand guard Guide bar Saw chain Lever Adjusting screw/dial Oil level sight Rear hand guard Lock-off button Chain catcher G...
Page 11 - Adjusting saw chain tension; Engaging extension cord; OPERATION; Switch action
11 Adjusting saw chain tension The saw chain may become loose after many hours of use. From time to time check the saw chain tension before use. 1. Loosen the sprocket cover lightly. 2. Keep lifting up the guide bar tip slightly to keep the guide bar horizontal. 3. Turn the adjusting screw / dial to...
Page 12 - CHECKS; Checking the chain tension; Checking the switch action
12 Reclaimend oil 006921 Lubricate the saw chain and bar using biologically degradable saw chain oil with an adhesion agent. The adhesion agent in the saw chain oil prevents the oil from being thrown off the saw excessively quickly. Mineral oils must not be used, as they are harmful to the environme...
Page 13 - Checking the chain brake; Checking the run-down brake; Adjusting the chain lubrication
13 Checking the chain brake NOTE: • If the chain saw fails to start, check whether the chain brake is released. To release the chain brake, pull the hand guard backwards firmly until you feel it engage. 1 2 3 014387 1 3 2 014439 Check the chain brake as follows: 1. Hold the chain saw with both hands...
Page 15 - MAINTENANCE; Cleaning the chain saw
15 (3) The base of the trunk is free of foreign objects, roots and ranches; (4) No persons or objects are present over a distance of 2 1/2 tree lengths in the direction in which the tree will fall. − Consider the following with respect to each tree: • Direction of lean; • Loose or dry branches; • He...
Page 16 - Sharpening the saw chain; Sharpen the saw chain when:
16 Sharpening the saw chain CAUTION: • Always withdraw the mains plug and wear safety gloves when performing work on the saw chain. 006924 Sharpen the saw chain when: − Mealy sawdust is produced when damp wood is cut; − The chain penetrates the wood with difficulty, even when heavy pressure is appli...
Page 17 - Cleaning the oil guide; New saw chains
17 30 006928 − After sharpening the chain, check the height of the depth gauge using the chain gauge tool (optional accessory). 014344 − Remove any projecting material, however small, with a special flat file (optional accessory). − Round off the front of the depth gauge again. Cleaning the guide ba...
Page 19 - TROUBLE SHOOTING; Malfunction status; OPTIONAL ACCESSORIES
19 TROUBLE SHOOTING Before asking for repairs, conduct your own inspection first. If you find a problem that is not explained in the manual, do not attempt to dismantle the tool. Instead, ask Makita Authorized Service Centers. No oil on the chain. Chain does not stop even the chain brake is engaged....
Page 20 - Makita Corporation