Repair And Fix it

There were only two engines available for the Massey Ferguson 175 over the span of the 11-year production run of this model. Both engines are 4-cylinder motors, one a diesel and the other gasoline powered. Only the latter has an ignition system, naturally. Troubleshooting a breaker point ignition system is a straightforward task, but all components involved must function correctly to deliver voltage where and when its needed.

Instructions

1

Set the multi-meter to the voltage scale that registers 0 to 20 volts. Check the voltage at the battery terminals. Charge the battery if the voltage is less than 12.5 volts. Clean the battery cable connections if any corrosion is present.

2

Turn the ignition switch to the run position. Measure the voltage at the primary side of the ignition coil. Replace the ignition switch or connecting wires if no voltage is present at the primary terminal of the ignition coil.

3

Measure the resistance of the primary ignition coil windings. Turn the ignition switch off and set the multi-meter to the lowest ohm scale. Place the tester leads on both ignition coil terminals. Replace the coil if resistance exceeds 5 ohms.

4

Replace the breaker points if they appear corroded or pitted. Replace the condenser, if no faults are found elsewhere. You can test the condenser with the proper equipment, but the cost of a new one is minimal.

Freon is a liquid/gaseous chemical compound commonly used in refrigerators, air conditioners, and freezers. Known by the chemical name chlorodifloromethane, it is a nontoxic and nonflammable material. Although freon does not burn at room temperature, it may combust when mixed with air (65 percent) at low pressure. Concentrations of chlorine may also induce combustion in chlorodifloromethane.

Thermal Decomposition

Freon poses a negligible fire hazard when it is directly exposed to heat or flames, but chlorides, fluorides, and phosgene are released as a result of the thermal decomposition of the gas. Notably, phosgene is a poisonous gas and poses a serious threat to health.

Car Fires

Freon is used as a refrigerant in car air conditioning systems, and older models have the R-12 variety of the gas. If such a car catches fire, it is important not to inhale the fumes because the R-12 will turn into phosgene (nerve gas), a lethal chemical.

Cylinder Explosion

Freon is compressed into self-pressure-releasing cylinders that may rupture because of extended exposure to fires over 900 degrees Celsius. Freon itself does not catch fire, but the cylinders containing the gas may explode if the fire is not controlled. This happens because of pressure buildup within the cylinders caused by the rise in surrounding temperature. The shards of a bursting cylinder pose a serious hazard.

Warning

Freon cylinders should be stored at room temperature to avoid accidental overheating of contents. If water is used for extinguishing a fire, it should be contained and neutralized before it is disposed. Use a self-contained breathing apparatus (SCBA) if the containers have leaked or have been damaged within an enclosed space. Inhaling freon poses a serious hazard to health, and exposure to higher concentrations of the gas can be fatal.