Section ill. TROUBLESHOOTING

Tighten all mounting bolts and loose or leaking hydraulic connections. Replace a

defective drive coupling (par. 153).

Hose assemblies. Inspect the hydraulic hose assemblies for loose connections. Inspect

the hose for cracks, breaks, and for frayed or rotten fabric covering.

Tighten hose connections and replace any defective hose assembly.

Tubing. Inspect all tubing for cracks, breaks, and distortion.

Tighten all tube connections. Replace any damaged or defective tube or fitting.

High pressure filter assembly. Inspect the filter for dirty or clogged condition resulting

in excessive pressure drop.

Remove and replace the filter element.

Thermoswitch. Inspect the thermoswitch for correct temperature response and for

secure installation.

Replace a defective or damaged thermoswitch (par. 143).

Section ill. TROUBLESHOOTING

79. General

followed by a list of probable causes of

stated is

This section provides information useful in

the trouble. The possible remedy recommended

diagnosis and correction, inspection, operation,

is described opposite the probable cause.

o r failure of the hydraulic test stand, or any

of its components. Each trouble symptom

80. Engine Hard to Start or Fails to Start

Probable cause

Possible remedy

Charge or replace defective battery (par. 9).

Battery defective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Inspect the choke valve for full open or closed position

Choking insufficient. . . . . . . . . . . . . . . . . . . . . . . . . . .

(par. 122).

Tighten loose connections.

Battery cables loose on terminals. . . . . . . . . . . . . . . . . . . . . .

Replace switch (par. 138).

Ignition switch faulty. . . . . . . . . . . . . . . . . . . . . . . .

Tighten loose connections.

Battery cable loose on armature relay. . . . . . . . . . . . . . . . . .

Remove spark plugs (par. 114) and crank the engine

Carburetor flooded. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

several times to drive out rich fuel mixture.

Test the spark (par. 115).

No ignition spark. . . . . . . . . . . . . . . . . . . . . . . . . . .

Clean and adjust or replace spark plugs (par. 114).

Spark plugs defective. . . . . . . . . . . . . . . . . . . . . .

Repair or replace magneto contact point set (par. 115).

Magneto faulty. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

81. Engine Misses or Runs Erratically

Probable cause

Possible remedy

Tighten carburetor mounting bolts. Replace gasket if

Carburetor gasket leaks

leak persists (par. 122).

Test spark (par. 115)

Spark weak. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Measure and reset spark plug gap (par. 11.4) .

Spark gap incorrect. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Tighten ignition wire connections.

Ignition wiring loose. . . . . . . . . . . . . . . . . . . .

Clean, adjust, or replace contact points (par. 115).

Magneto contact points pitted or incorrectly adjusted

Repair governor (par. 135).

Governor defective

82. Engine Stops Suddenly

Possible remedy

Probable cause

Repair or replace fuel pump (par. 131).

Fuel pump defective

Remove and clean fuel line, replace if defective (par.

F u e l line clogged

131).

Replace defective contact set (par. 115) .

M a g n e t o contact set defective

AGO 5742A