Husqvarna 435 II and 440 II chain and service checks

Two 41 cc saws with the same tanks and the same plug

The Husqvarna 435 and 440 are two-stroke chainsaws with a 40.9 cc (2.49 cubic inch) engine that idles at 2,900 RPM. The 435 is rated 1.6 kW (2.2 hp) and the 440 1.8 kW (2.4 hp), both at 9,000 RPM. They weigh 9.7 pounds (4.4 kg) without bar and chain and share their plug, fuel tank and chain oil tank.

As two-strokes they have no sump, and a separate automatic pump feeds the chain.

Before you fill the tank, shake the container and make sure the fuel is fully mixed. The manual’s steps are to stop the engine and let it cool, clean the area around the cap, shake the container, remove the cap slowly and fill the tank.

The Husqvarna 435 and 440 chainsaws schedule

The saw has Husqvarna’s AirInjection system, which removes dust before it reaches the air filter. Drain and clean the fuel tank and chain oil tank regularly, since contamination in the tanks causes malfunction. The 455 and 460 Rancher page covers the bigger saws.

Parts to buy for the Husqvarna 435 and 440 chainsaws

Both saws run on a 50:1 mix.

The 435 and the 440 compared, so you buy the right chain and parts

One comparison notes that both saws share the same 40.9 cc X-Torq engine block and differ in rated output (2.2 hp for the 435, 2.4 hp for the 440), with the weight difference marginal, and recommends the 440 for landowners cutting 2 to 4 cords of firewood a year.

Because the engine is shared, the fuel mix, spark plug and air filter in the tables above apply to both, and the difference to check when buying a chain or bar is the model-specific chain pitch and length rather than anything in the engine.

Starting a Husqvarna 435 or 440 cold and warm, and what the chain brake will not do

Husqvarna's operator’s manual starts every procedure with the chain brake engaged by pushing the front hand guard forward. For a cold engine you then pull the start/stop switch out and up to the choke position, push the air purge bulb about six times or until fuel begins to fill it (it says a full bulb is not necessary), and push the switch down before pulling the cord. For a warm engine the same steps apply, but you set the choke first and then push the switch back down.

The manual is unusually candid about kickback. It says the inertia release will not always engage the chain brake, because the chain brake must first be working as intended and the force of the kickback must be large enough. The brake will not always protect you either, since if you are close to the bar it may not stop the chain before it reaches you, and some hand positions cannot touch the hand guard at all.

It ends the section with a plain line: only you and correct working technique can prevent kickbacks.

Two checks the 435 and 440 manual asks for every time

To check the chain brake, start the saw, hold it tightly with the chain clear of the ground, apply full throttle and tilt your left wrist against the front hand guard. The chain must stop immediately, and you must not let go of the front handle. Then check the throttle: release the trigger and make sure the chain stops and stays stationary.

If it rotates at idle, the manual says to speak to a servicing dealer and not use the saw.

For the carburetor you may adjust only the idle speed screw. Start the saw, turn the screw clockwise until the chain begins to rotate, then turn it counterclockwise until the chain stops. The idle is correct when the engine runs as intended in every position and sits safely below the speed at which the chain starts to move.

If the chain will not stop, do not use the saw. The low and high speed needles are left to a dealer.

435 and 440 ratings, capacities and storing the saw

The technical data lists both saws at 40.9 cm³ (2.49 cu in) with an idle speed of 2,900 RPM. The 435 is rated at 1.6 kW (2.2 hp) and the 440 at 1.8 kW (2.4 hp), both at 9,000 RPM. Each weighs 9.7 lb (4.4 kg), holds 0.78 US pint (0.37 L) of fuel and 0.53 pint (0.25 L) of chain oil through an automatic pump, and takes 13 to 18 inch bars in 0.325 inch pitch with 0.050 inch drive links and a seven-tooth spur sprocket.

Husqvarna says both models met ANSI B175.1-2012 and CSA Z62.3 kickback requirements when fitted with its listed low-kickback chain and bar combinations.

For transport and storage, it says to empty the fuel and chain oil tanks first, take the spark plug cap off, engage the chain brake and fit the transportation guard. For long-term storage, let the saw cool, take the bar and chain off and clean both and the groove in the bar, because a dirty chain and bar can become rigid or blocked, then attach the transportation guard, clean the saw and have it fully serviced.

Bars, chains and filing angles Husqvarna lists for the 435 and 440

The accessories page of the manual names the only bar and chain combinations Husqvarna recommends for these two saws. Bars are 13, 15, 16 or 18 inches with a 0.325 inch pitch, 0.050 inch (1.3 mm) gauge and a 10T maximum nose radius.

The low-kickback chains are the Husqvarna SP33G and H30, with 56 drive links on the 13 inch bar, 64 on the 15, 66 on the 16 and 72 on the 18. Its warning is that other chainsaw models may not meet the kickback standard with these combinations, so the list applies to the 435 and 440 only.

For sharpening, Husqvarna recommends a 4.8 mm (3/16 inch) round file used in a Husqvarna file gauge, part 586 93 84-01 for the SP33G and 505 69 81-08 for the H30, with a 30° filing angle. The manual says the force of a kickback increases a lot if you do not follow the sharpening instructions, and that the risk rises if the depth gauge setting is too large. It recommends adjusting the depth gauge after every third time you sharpen the cutting teeth, and using Husqvarna's depth gauge tool.

Husqvarna 435 and 440 against the Rancher 455 and 460

The manuals show how far apart the two families are. The 435 and 440 are 40.9 cm³ saws weighing 9.7 lb (4.4 kg), with a 0.78 US pint fuel tank and 0.53 pint chain oil tank, 13 to 18 inch bars in 0.325 inch pitch, and no decompression valve. The 455 and 460 Rancher are 55.5 and 60.3 cm³, weigh 13.2 lb (6.0 kg), carry 0.93 pint of fuel and 0.68 pint of chain oil, and use 3/8 inch pitch bars from 15 to 24 inches with an 11T nose.

The Rancher starts with a decompression valve, which the smaller saws do not need.

In practice the 435 and 440 are the lighter saws for limbing and firewood, where low weight matters for overhead work. The Ranchers suit larger diameter wood and longer bars, where the extra 3.5 lb (1.6 kg) and the higher output of 2.6 to 2.7 kW are worth carrying. The two families call for different files and filing angles too, 4.8 mm and 30° for the 435 and 440 and 5.5 mm with 25° or 30° for the Rancher.

Reading the Husqvarna warnings on a 435 or 440 before the first cut

The safety chapter of the 435 and 440 manual is where Husqvarna puts the rules an owner is least likely to have read. It says never to use the saw when fatigued or under the influence of alcohol, drugs or medication, never in bad weather such as dense fog, heavy rain, strong wind or intense cold, and never with visible damage to the spark plug cap and ignition cable, because of the risk of sparking. It says never to start the saw unless the guide bar, chain and all covers are fitted correctly, because without a bar and chain the clutch can come loose and cause serious injury, and not to attempt pruning or limbing in a standing tree unless specifically trained to.

For kickback, the manual's warning is that it can occur when the guide bar tip touches an object, causing a lightning fast reverse reaction that throws the guide bar up toward the operator. It adds that a lack of concentration can lead to kickback if the kickback zone of the bar accidentally touches a branch, a nearby tree or another object. The start/stop switch returns to the start position by itself, so the manual says to remove the spark plug cap when assembling the saw or doing maintenance, to prevent an accidental start.