Repair instructions

8

When replacing the cylinder 340, 345: Unscrew the decompression valve. (345) Remove the intake system, see “Air intake system

– removal”.

Model 350 is fitted with a spacer, which is secured using four bolts from the underside. The spacer does not however need to be removed when removing the cylinder.

Cleaning and inspection

Clean all the components, scraping off all traces of old gasket and carbon from the following places:

Piston crown

Top of the cylinder bore

Cylinder exhaust port

Decompression valve channel (340, 346XP, 350, 351, 353)

Cylinder base and/or crankcase

Check the following:

The surface coating of the cylinder is not worn through, especially in the upper part of the cylinder.

The cylinder is free from score marks and areas of wear.

The piston is free from score marks. Small scratches can be polished out with fine emery paper.

The piston ring is not burnt into its groove.

Measure piston ring wear. This should not exceed 1 mm. Use the piston to push down the piston ring.

The needle roller bearing is undamaged.

The inlet manifold is undamaged.

Pressure test the decompression valve.

Also refer to Jonsered’s Analysis guide for piston failures, art. no. 108 07 01-01.

Decompression valve – pressure testing

1

Connect tool 502 50 38-01 to the decompression valve.

2

Pump up the pressure to 80 kPa (0.8 bar).

3

Wait 30 seconds.

4

The pressure should not be less than 60 kPa (0.6 bar).

42 – English

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Husqvarna 340, 345, 346XP,350, 351, 353 manual Cleaning and inspection, Decompression valve pressure testing

340, 345, 346XP,350, 351, 353 specifications

Husqvarna is renowned for its high-quality chainsaws, and the Husqvarna 340, 345, 346XP, 350, 351, and 353 models are no exceptions. These models have garnered a reputation among both professional and amateur users for their reliability, durability, and cutting performance.

The Husqvarna 340 is an entry-level model designed for homeowners and light-duty tasks. It features a 40cc engine that provides a good balance of power and weight, making it easy to handle during extended use. The 340 is equipped with low-vibration technology, significantly reducing operator fatigue and making it suitable for less experienced users.

The Husqvarna 345 is slightly more powerful than the 340, boasting a 45.7cc engine. This model is ideal for users who require a bit more power for medium-duty tasks. It incorporates the air injection system, which helps to separate larger debris before it reaches the air filter, prolonging the life of the filter and maintaining optimal performance.

Moving up the range, the Husqvarna 346XP is a powerful professional chainsaw tailored for demanding tasks. With a 50.2cc engine and the X-Torq engine technology, it provides high cutting performance while reducing fuel consumption and emissions. The 346XP features an adjustable oil pump that allows for precise lubrication, making it an excellent choice for commercial users.

The Husqvarna 350 shares similarities with the 346XP but is designed for users who need a well-rounded saw for various applications. Its 50.2cc engine delivers ample power, and the ergonomically designed handle provides comfort during prolonged use. The chainsaw's advanced starting system ensures easy ignition, even in challenging conditions.

The 351 is another versatile option, equipped with a 50cc engine, designed for both professional and home use. It emphasizes user comfort and ease of handling. The compact design combined with features such as an efficient air filtration system makes the 351 suitable for long hours of work.

Lastly, the Husqvarna 353 is a heavy-duty model that excels in performance and longevity. It has a 50cc engine and incorporates various safety features, including a chain brake and throttle lock, to ensure safe operation. The saw also utilizes the unique anti-vibration system, minimizing vibrations that can lead to user fatigue.

In summary, the Husqvarna 340, 345, 346XP, 350, 351, and 353 models each offer distinct features catering to a wide range of users. From homeowners tackling light tasks to professionals requiring rugged performance, these chainsaws showcase Husqvarna's commitment to quality, innovation, and user-centric design.