Husqvarna 1151375-95, 338XPT EPA III manual Maintenance, Carburetor

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MAINTENANCE

Carburetor

Your Husqvarna product has been designed and manufactured to specifications that reduce harmful emissions. After the engine has used 8-10 tanks of fuel the engine will be run-in. To ensure that it continues to run at peak performance and to minimise harmful exhaust emissions after the running-in period, ask your dealer/ service workshop (who will have a rev counter at their disposal) to adjust your carburettor.

Function, Basic settings, Fine adjustment

WARNING! Do not start the chain saw

! unless the bar, chain and clutch cover (chain brake) are fitted, otherwise the clutch may come loose and cause personal injury.

Function

•The carburetor governs the engine’s speed via the throttle control. Air and fuel are mixed in the carburetor. The air/fuel mixture is adjustable. Correct adjustment is essential to get the best performance from the machine.

•The setting of the carburetor means that the engine is adapted to local conditions, for example, the climate, altitude, fuel and the type of 2-stroke oil.

•The carburetor has three adjustment controls:

-L = Low speed jet

-H = High speed jet

-T = Idle adjustment screw

H L

T

•The L and H-jets are used to adjust the supply of fuel to match the rate that air is admitted, which is controlled with the throttle. If they are screwed clockwise the air/fuel ratio becomes leaner (less fuel) and if they are turned anti-clockwise the ratio becomes richer (more fuel). A lean mixture gives a higher engine speed and a rich mixture gives a lower engine speed.

•The T-screw regulates the throttle setting at idle speed. If the T-screw is turned clockwise this gives a higher idle speed; turning it anti-clockwise gives a lower idle speed.

Basic settings and running in

The basic carburetor settings are adjusted during testing at the factory. The basic setting is richer than the optimal setting and should be maintained for the first few hours the machine is in use. The carburettor should then be finely adjusted. Fine adjustment should be carried out by a skilled technician.

CAUTION! If the chain rotates while idling the T-screw must be turned anti-clockwise until the chain stops.

Rec. idle speed: 2800 rpm

Fine adjustment

When the machine has been ”run-in” the carburetor should be finely adjusted. The fine adjustment should be carried out by a qualified person. First adjust the L- jet, then the idling screw T and then the H-jet.

Fine tuning may be required if the chain saw, after changing the type of fuel, performs differently with regard to starting, acceleration, maximum speed, etc.

Conditions

•Before any adjustments are made the air filter should be clean and the cylinder cover fitted. Adjusting the carburetor while a dirty air filter is in use will result in a leaner mixture next time the filter is cleaned. This can give rise to serious engine damage.

•Carefully turn both jets, L and H, so that they are midway between fully screwed in and fully screwed out.

•Do not attempt to adjust the L and H jets beyond either stop as this could cause damage.

•Now start the machine according to the starting instructions and let it warm up for 10 minutes. CAUTION! If the chain rotates while idling the T- screw must be turned anti-clockwise until the chain stops.

•Place the machine on a flat surface so that the bar points away from you and so that the bar and chain do not come into contact with the surface or other objects.

Low speed jet L

Turn the low speed jet L clockwise until it stops. If the engine accelerates poorly or idles unevenly, turn the low speed jet L anticlockwise until good acceleration and idling are achieved.

CAUTION! If the chain rotates while idling the T-screw must be turned anti-clockwise until the chain stops.

Fine adjustment of the idling speed T

Final setting of the idling speed T

Adjust the idle speed with the T-screw. If it is necessary to re-adjust, turn the T-screw clockwise while the engine is running, until the chain starts to rotate. Then turn counter- clockwise until the chain stops. A correctly adjusted idle speed setting occurs when the engine runs smoothly in every position. It should also be good margin to the rpm when the chain starts to rotate.

WARNING! Contact your servicing

! dealer, if the idle speed setting cannot be adjusted so that the chain stops at idle. Do not use the chain saw until it has been properly adjusted or repaired.

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Contents 334T 338XPT EPA III, Carb Symbols on the machine KEY to SymbolsSymbols in the operator’s manual You will find the following labels on your chain sawContents Dear customer IntroductionWhat is what on the chain saw? What is WHAT?Always use common sense General Safety PrecautionsBefore using a new chain saw Personal protective equipment Machine′s safety equipmentChain brake and front hand guard Vibration damping system Throttle lockoutChain catcher Cutting equipment Stop switchMuffler General rulesCutting equipment designed to reduce kickback Sharpening your chain and adjusting depth gauge settingBar ChainToo large General advice on adjusting depth gauge settingIncreased if the depth gauge setting is Tensioning the chain Adjustment of depth gauge settingLubricating cutting equipment Bar and cause serious or even fatal injuryChain drive sprocket Filling with chain oilChecking chain lubrication Checking wear on cutting equipment Working with the chain AssemblyFitting the bar and chain Fuel Fuel HandlingFueling Fuel safetyTransport and storage Long-term storageStarting and stopping Starting and StoppingCold engine Warm engineStopping Working Techniques Basic safety rulesBefore use General working instructionsDo not let go of the handles General requirements working at height Using the chainsaw in the treePreparing to use the saw in the tree Securing the work position for two-handed useBasic cutting technique Limbing Felling technique for tree topsLog is supported at both ends. There is a high risk Felling cut Felling directionDirectional cuts Cutting trees and branches that are in tension General adviceFreeing a tree that has fallen badly Cutting the trunk into logs How to avoid kickbackWhat is kickback? Carburetor MaintenanceHigh speed jet H Correctly adjusted carburetorChecking brake band wear Checking the front hand guardImmediately Changing a broken or worn starter cord MufflerStarter Tensioning the recoil spring Air filterChanging a broken recoil spring Fitting the starterWhen making adjustments Adjustment of the oil pumpSpark plug Lubricating the bar tip sprocketDaily maintenance Weekly maintenance Monthly maintenance Maintenance scheduleTechnical data Technical DataSaw chain filing and file gauges Bar and chain combinations, model 334TBar and chain combinations, model 338XPT Your Warranty Rights and Obligations What is not Covered Safety precautions for chain saw users American Standard Safety PrecautionsKickback safety precautions Other safety precautionsPage ´z+SE¶5j¨ Page 1151375-95

1151375-95, 338XPT EPA III specifications

The Husqvarna 338XPT is a powerful chainsaw designed specifically for professionals who require reliability and performance in demanding environments. One of its standout features is the lightweight design, making it easy to maneuver while still delivering impressive power. Weighing in at just over 10 pounds, the 338XPT allows users to work for extended periods without fatigue, making it an ideal choice for arborists and forestry workers.

At the heart of the Husqvarna 338XPT is its efficient engine, which not only provides robust cutting performance but is also designed with EPA III compliance in mind. This means the machine adheres to strict environmental regulations, producing lower emissions while ensuring a high power output. The X-Torq engine technology is one of the key innovations that contribute to its efficiency. This technology reduces fuel consumption by up to 20% while also decreasing harmful exhaust emissions. This dual benefit makes the 338XPT a viable option for users who prioritize both performance and environmental responsibility.

Another notable characteristic of the Husqvarna 338XPT is its advanced air filtration system, which enhances the durability of the engine by ensuring that only clean air reaches it. The centrifuge air cleaning system significantly prolongs the time between filter cleanings, allowing users to focus more on their work and less on maintenance. This feature is particularly beneficial in dusty or dirty job sites, ensuring optimal performance in various conditions.

Comfort and usability are also central to the design of the 338XPT. The chainsaw includes an ergonomic handle that allows for better control during operation, reducing vibrations and enhancing user comfort. Additionally, the chainsaw's easy-access chain tensioning system makes adjusting the chain as simple as possible, ensuring that users can quickly get back to their tasks at hand without unnecessary delays.

For safety-conscious users, the Husqvarna 338XPT is equipped with features like a combined choke/stop control that allows for easy starting and reduces the risk of engine flooding. Furthermore, the chainsaw's inherent balance and lightweight structure contribute to safer handling and operation.

In summary, the Husqvarna 338XPT EPA III is a top-of-the-line chainsaw that combines power, efficiency, and user-friendly features, making it a prime choice for professionals in the forestry and arborist fields. Its robust engine technology, advanced air filtration, and ergonomic design ensure that you can tackle any job with confidence and ease.
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