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Transfer Switch Sequence of Operations

Every year we encounter a number of generators that go under water. Although this can be devastating, prompt measures will minimize the damage. 

Make sure all electrical power is turned off to the generator and automatic transfer switch. Don’t forget to de-energize the battery charger, coolant heater, oil heater, and any other electrical appliance associated with your generator.

After you are sure all AC power is turned off, make sure the generator and automatic transfer switch are in the off or stop mode.

Disconnect the cranking battery. Always disconnect the negative terminal first. You should remove the battery to another location and recharge it. Also, check the electrolyte level. Refill with distilled water. If the battery was submerged, don’t expect much life. You may have to replace it.

If the generator was not running when it went under water, the damage will most likely be minimal and confined to shorted DC circuits. I have often found these units undamaged after I cleaned them up and dried them out.

If, however, the generator was running when it went under water, it may have serious engine damage due to hydraulic lock. This happens when liquid is drawn into the combustion chamber. Since water cannot be compressed, it will stop the engine instantly. The sudden stop can break or bend engine parts and damage gaskets.

I use plenty of fresh water. Just hose it down. Do not use soap or solvents! Clean water is a poor electrical conductor, but when mixed with almost anything it becomes a very good conductor. So, never use soap.

Rinse down everything, even the electrical components. Open the control panel and transfer switch (make sure it is de-energized!!!) and thoroughly clean out all mud, salt, and other residue.

Then let everything dry. Take out all enclosed relays. Open, rinse, and dry these separately or replace them. It will take a day of good weather to dry out completely, and it must be dry before you turn the electrical power back on.

Drain the engine oil. Replace this with fresh oil and be prepared to flush the system by changing the oil three or four times. 

Remove all the spark plugs or fuel injectors. Disconnect the ignition wire to the fuel solenoid and ignition system. You don’t want an accidental spark.

Then pour rubbing alcohol into the intake manifold and cylinders. (Pour it into the spark plug or injector holes) All you need is a few ounces in each cylinder.

You will need a barring tool or something to use to rotate the engine. Be sure to turn the engine over counterclockwise. (Look at the fan. It should push air forward through the radiator) Rotate the engine 10 complete revolutions. Alcohol will run out and make a mess. Don’t worry about the mess, but don’t smoke. Alcohol is flammable.

Repeat this process 3 times. Then change the oil again. The oil will now be contaminated with alcohol and water. 

Rinse the distributor and cap with alcohol. (Make sure you don’t make a spark!!!)

Rinse the intake manifold and carburetor with alcohol. If your generator runs on natural gas or LPG you will have to disassemble the fuel system and rinse it with alcohol. 

If you have a diesel system, you will need to remove the water. Diesel floats above the water, because of this you need not dispose of the fuel, but you will need to clear the water out of the system and change the fuel fiters.

Let everything dry out for 24 hours. Keep the equipment covered to protect it from rain.

After the equipment is dry, disconnect the power source to the voltage regulator. Re-install the battery. Do not re-install the sparkplugs or injectors yet.

Using a jumper wire, short the battery positive to the starter solenoid to make the engine crank over. Crank the engine over for at least 20 seconds. Check to see if water or alcohol was ejected from the cylinders. If water was ejected repeat the alcohol rinse process. If nothing is ejected or if only alcohol is ejected re-install the spark plugs or injectors. Crank the engine over for 60 seconds then change the oil again. (Also, change the oil filter)

Next, reconnect the ignition wire and the wire to the fuel solenoid. Now try to start the generator from the generator control panel. 

If the generator starts, let it run enough to warm up. Check the engine gauges. Make sure the exhaust system is clear and let it dry out. The engine will probably shake and miss a lot. This should clear up.

After the engine smoothes out, shut the generator off. Reconnect the voltage regulator. Make sure the output breaker is turned off so that you don’t energize the automatic transfer switch, then restart the generator. 

Check to see if AC voltage comes up. If it does, turn the generator off.

Now, go to the automatic transfer switch. Make sure it is dry. If it is, turn the electrical power back on and turn the automatic transfer switch back to automatic. Check the time delay indicators. Wait until all timers have timed out and the time delay on start light has gone out.

Turn the generator control back to automatic or remote. Close the output breaker. 

Now it is time to test the system under load. You may use the test mode on the automatic transfer switch or turn the utility power off. Good luck!

If you rinsed the equipment with clear, clean water and allowed everything to dry, your equipment will not be damaged by this cleaning operation. Any damage, and there may well be some, happened when the generator went underwater. Floodwater is not clean and is a good conductor. It may have shorted energized electrical components as the water rose.

If the system doesn’t work properly, call us. We can help you diagnose the problems. We can provide parts, manuals, wiring diagrams, and even send a technician if you want one.

Our technicians are required to drink huge amounts of coffee. They will be awake and waiting for your call.

9/30/99

PH

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