Cylinder; Breather Valve (Reed Valve); Valve Clearance Check And Adjustment; Crankcase - Pioneer 1200 Maintenance Service Manual

FE400 ENGINE
2. Use a wire type gauge. Bend the outside or ground electrode so only a slight drag on the gauge is felt
when passing it between the electrode. Never make an adjustment by bending the center electrode. Set
gap (A) to 0.027 - 0.031 inches (0.69 - 0.79 mm) (Figure 13-1, Page 13-2).
Spark Plug Installation
NOTE: Before installing the plug, check the condition of the threads in the cylinder head. Soften deposits
in cylinder head threads with penetrating oil and clean the threads with a tap if necessary.
Use a high temperature, anit-seize lubricant on the threads of the spark plug to reduce friction
when installing a new plug, and reduce 'gauling' and thread seizing for future replacements.
1. Install the spark plug and thread it in until finger-tight, then tighten the spark plug to 20 ft-lb (27 N·m).

CYLINDER

See General Warning, Section 1, Page 1-1.
Test cylinder compression using a standard compression tester. Low compression would normally indicate a
problem in the cylinder assembly such as defective rings, gaskets, etc.
The FE400 model engines are equipped with an automatic compression release valve (ACR). This valve
releases compression pressure at normal cranking RPM, resulting in lower compression. At a normal crank-
ing speed of 550 - 600 RPM, the compression should be typically 71 psi. This value could vary slightly
depending on wear of components affecting compression. See Transaxles and Engines Manual for inspection
and repair.

BREATHER VALVE (REED VALVE)

The function of the breather is to create a vacuum in the crankcase which prevents oil from being forced out
of the engine through the piston rings, oil seals or gaskets. The breather has a reed valve which limits the
direction of air flow caused by the piston moving up and down. Air can flow out of the crankcase, but the one-
way reed valve blocks return flow and therefore maintains a vacuum in the crankcase.
Oil laden air in the crankcase passes through the reed valve and expands into the rocker chamber. In the
rocker chamber most oil separates from the air and drains back to the crankcase. The air passes through a
tube and vents to the intake manifold. See Transaxles and Engines Manual for inspection and repair.

VALVE CLEARANCE CHECK AND ADJUSTMENT

No clearance check or adjustments are required. The FE400 engines are equipped with hydraulic lifters that
automatically eliminate all clearance in the valve train components.

CRANKCASE

See General Warning, Section 1, Page 1-1.

ENGINE REMOVAL

To perform repairs on crankcase components, remove engine from the vehicle. See following CAUTION.
CAUTION
• Before removal and disassembly, clean the engine.
2003 Pioneer 1200/1200SE Gasoline Vehicle Maintenance and Service Manual
13
Cylinder
Page 13-3