P 15/ 19

Repair

[4]DISASSEMBLY/ASSEMBLY

[4]-8. Engine (cont.)

DISASSEMBLING

Note: Cam gear assembly functions as automatic decompression valve system.

Valve is slightly open to release the compressed air in Engine at the starting time, before moving fly weight by centrifugal effects. It means the insufficient setting of Cam gear assembly will cause engine stall/ extreme reaction force at engine running due to too much load by the compressed air.

(11)Remove Pin 5 that sets Rocker arm assembly in place on Cylinder head complete. (Fig. 54) Use 1R308 to push out Pin 5.

The distinction of Rocker arm assembly and Push rods (for use of the exhaust system/ intake system) enables you shortens the repair process (Gap adjustment between Rocker arms and Retainers is even difficult, however, you can adjust it by using 1R366. Refer to Fig. 68.

Fig. 54

Pin 5

Cylinder head complete

the hole of Cylinder head complete

 

Rocker arm assembly

 

Exhaust

Intake

 

system

system

Note: Intake system of Rocker

 

 

 

Intake

arm has to be close to

Exhaust

the hole of Cylinder head

push-rod

push-rod

complete.

Important: Disassemble the parts in the room on Cylinder head complete before removing it and clean the clogged portions in the following steps. You may repair successfully without doing the step (5) and later in the next page.

(1)Remove Rocker cover complete, then push out Pin 5 on hinge for Rocker arms with 1R308 and remove Rocker arms. (Refer to Figs. 50 and 54)

(2)Remove Spark plug. Turn Flywheel until Piston comes to the upper dead point by looking through Spark plug hole on Cylinder head complete.

Note: Align the rib as a mark on Flywheel with the rib on Cylinder block as drawn in Fig. 55.

(3)Insert a bent Lead wire #16 into Combustion chamber through Spark plug hole so that Valves do not fall into Combustion chamber. (Fig. 56)

(4)While compressing Compression spring 11 by pushing Retainer with 1R003 attached with 1R389, remove Cotter by a thin bit magnetized by 1R288.

Routes in Cylinder head complete, the upper surface on Valves and the room on Cylinder head complete can be clean through removal of four Cotters, two Retainers, and two Compression springs 11.

Fig. 55

Rib on Cylinder block

 

Rib on Flywheel

Fig. 56

 

Use Cotter removal

1R389

attachment to push

 

Retainer.

 

 

1R003

[viewed from the upper side of the room]

Fig. 57

Retainer (2 pcs.)

Cotter (4 pcs.)

Compression spring 11 (2 pcs.)

Cylinder head complete

Note: Intake valve has to be close to this hole of Cylinder head complete.

Intake valve

Exhaust valve

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Image 15
Makita EK7650H, EK7651H dimensions Arm has to be close to
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EK7650H, EK7651H specifications

The Makita EK7650H and EK7651H are robust and powerful cut-off saws designed for professional contractors and construction workers. These models are ideal for cutting through concrete, masonry, asphalt, and other tough materials with precision and efficiency. Their advanced engineering and innovative features set them apart in the competitive landscape of power tools.

One of the standout features of both models is the 4-stroke engine technology, which provides a significant reduction in emissions and noise compared to traditional 2-stroke engines. This makes them environmentally friendly while also allowing for longer operating times without the need for frequent fuel refills. The powerful 6.6 HP engine delivers exceptional cutting performance, enabling users to tackle even the most challenging jobs.

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In summary, the Makita EK7650H and EK7651H are powerful, efficient, and user-friendly cut-off saws that cater to the needs of professional users. With their advanced features, including a 4-stroke engine, ergonomic design, and versatility in blade sizes, these saws are indispensable tools for anyone looking to perform cutting tasks with precision and ease.
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