NOTE

•The engine may be damaged if the choke lever is moved further beyond the “CLOSE” position.

•If the engine stops with an explosion sound or if the engine started, but stopped before operation of the choke lever, return this lever to the “OPEN” position and pull the starter handle several times to start the engine again.

•If the operator keeps pulling the starter handle several times with the choke lever left in the “CLOSE” position, the engine may be difficult to start because of over-suction of the fuel.

•In case of over-suction of the fuel, remove the spark plug and pull the handle several times rapidly to discharge any excess fuel. Dry the spark plug electrode.

•When the throttle valve does not return to a position in contact with the idling adjusting screw even if the throttle lever is set to the low speed, correct the control cable catching state to ensure proper return of the valve.

2)When the engine is warm

(1)Place the engine on a flat ground.

(2)Press the primary pump several times.

(3)Confirm that the choke lever is open.

(4)Hold the main handle with a left hand to prevent the engine from moving, settle down to take the stable position.

(5)Pull out slowly the starter handle till a certain resistance is felt. Return the starter handle backward once from this position, then pull it out with force.

(6)When the engine is difficult to start, open the throttle valve by about 1/3.

2. Stopping

1) When the cruise control lever is OFF

Release the trigger lever to reduce the engine speed, and set the stop switch to the “O” position.

2) When the cruise control lever is ON

Set the cruise control lever to the OFF position, reduce the engine speed, and set the stop switch to the “O” position.

Cruise control lever

OFF

ON

 

 

ADJUSTMENT OF IDLING

DANGER

The carburetor is the adjustment being completed at the time of factory shipment. Please do not adjust other than idling adjusting. When adjustment becomes necessary, please consult your dealership or an authorized service agent.

Checkup of low-speed rotation

Set the low-speed rotation to 3500 ( /min).

•If it is necessary to change the rotation speed, regulate the adjusting screw, with Phillips screwdriver.

•Turn the adjusting screw to the right, and the engine rotation will increase. Turn the adjusting screw to the left, and the engine rotation will drop.

Adjusting screw

Carburetor

12

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Dolmar PB-250.4 instruction manual Adjustment of Idling, Stopping, Checkup of low-speed rotation
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PB-250.4 specifications

The Dolmar PB-250.4 is a robust and efficient backpack blower designed for both commercial and residential use. Known for its powerful performance and user-friendly operation, the PB-250.4 stands out as a reliable choice for landscaping professionals and homeowners alike.

One of the main features of the Dolmar PB-250.4 is its impressive engine. Equipped with a 24.5 cc, 2-stroke engine, it delivers a commendable airflow of up to 700 CFM (cubic feet per minute) and a maximum airspeed of 160 mph. This power allows users to tackle heavy debris, leaves, and grass clippings with ease, making yard maintenance swift and effective.

The design of the PB-250.4 emphasizes comfort and ergonomic use. It comes with a padded shoulder harness, which distributes the weight evenly and reduces fatigue during extended use. Additionally, the adjustable throttle and ergonomic handle provide better control and precision, enhancing the overall user experience.

The technology behind the Dolmar PB-250.4 reflects a commitment to efficiency and environmental responsibility. The blower incorporates the advanced 2-stroke engine technology, which not only provides superb power but also integrates a clean-air system that reduces emissions, making it a more eco-friendly option compared to older models.

Easy starting is another characteristic that sets the PB-250.4 apart. The blower is equipped with a reliable starting system that minimizes resistance for an effortless start, even in cold conditions. This feature is particularly beneficial for users who may need to start and stop the blower frequently throughout their tasks.

Maintenance of the PB-250.4 is straightforward, thanks to its accessible components and design features. The air filter can be easily cleaned and replaced, ensuring that the engine runs optimally with minimal downtime.

In summary, the Dolmar PB-250.4 is a high-performance backpack blower that combines power, efficiency, and comfort in a user-friendly package. Its robust engine, ergonomic design, and commitment to low emissions make it an excellent choice for anyone looking to maintain their outdoor spaces effectively. Whether for professional landscaping or home use, the PB-250.4 delivers the performance and reliability users demand.
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