construction. The differences are mainly in pressure plate assemblies, linkages, and overall size.

Of the different types of clutch assemblies, the one shown in figure 7-8 is known as the plate clutch. The plate clutch is a simple clutch with two plates and one disk, clamped between the two plates. Another type (fig. 7-9) is the double-disk clutch. The driving members of the single-disk clutch consist of the flywheel and driving (pressure) plate. The driven member consists of a single disk splined to the clutch shaft and faced on both sides with friction material. When the clutch is fully engaged, the driven disk is firmly clamped between the flywheel and the driving plate by the pressure of the pressure plate springs, and a direct, nonslipping connection between the driving and driven members of the clutch is formed. In this position, the driven disk rotates the clutch shaft to which it is splined. The clutch shaft is connected to the driving wheels through the power train.

The double-disk clutch is substantially the same as the single-disk clutch described in the section above, except that an additional driven disk and intermediate driving plate are added.

For more basic information concerning clutches refer to your Construction Mechanic 3&2 TRAMAN NAVEDTRA 10644-G1.

Figure 7-8. - Single-disk clutch assembly.

Figure 7-9. - Doubledisk clutch assembly.

CLUTCH MALFUNCTIONS

The information given in this section is general and may be applied to nearly every type of clutch you are likely to encounter. Refer to the manufacturer's repair manuals for problems not listed here.

The most common symptoms of clutch malfunctions are dragging, slipping, and noise. Improper adjustment is one condition that leads to clutch problems. You should always adjust the clutch according to the manufacturer's specifications. An improperly adjusted clutch can cause clutch slippage and hard shifting.

Dragging

This condition results when the clutch disk does not completely disengage from the flywheel or pressure plate when the clutch pedal is depressed. As a result, the clutch disk tends to continue turning with the engine and attempts to drive the transmission.

Dragging may be caused by any of the following conditions:

1. Excessive free travel in the clutch linkage.

2. The clutch disk binding on the transmission input shaft.

3. A warped or damaged pressure plate.