INTERNAL COMBUSTION ENGINES

INTERNAL COMBUSTION ENGINESSECTION 4CONTROL OF OPERATION OF IC ENGINES

CONTROL OF OPERATION OF IC ENGINESThe instrument panel

1.The instrument panel provides a control location for the controls and gages needed to operate an IC engine.

The engine is operated by the operator from the (Instrument panel / Engine itself) .

Instrument panel

2.Here is a drawing of a simplified Instrument panel.

Gages on this Instrument panel show the oil.., the oil, the water., and the water.

Level, Pressure, Level, Temperature

3.The ignition switch (Opens / Closes) the electrical circuit when the engine is to be started.

Closes

4. Engine speed is controlled by the ..Throttle

5. Engine speed may also be automatically controlled by a ..Governor

6. To check on the operation of the cooling system, you look at the ......gage.

Water temperature

7. If the oil pressure gage shows an excessively high reading, the .system is malfunctioning.

Lubricating

8. An oil filter may be ..

Blocked / Clogged

9. Sight gages show the .of oil in the lubricating system and the of water in the cooling system.

Level, Level

Prestart Procedures

10. Manufacturers always furnish operation and maintenance manuals for the engines.

The manual contains starting, stopping, and control procedures. Every operator should study and know these procedures before he tries to.the engine.

Start

11. The operator who is familiar with the manual and the engine, can usually detect malfunctions before they cause serious troubles.

Once a malfunction is detected, the operator must know how to .the engine before damage is caused to the engine.Stop

12. A new engine, an overhauled engine, or one that has been idle for a long time should be thoroughly ..before startup.

CheckedAn experienced operator knows how to proceed, but a new operator may need to use a PRESTART CHECKLIST to get the engine ready to start. Each company has its own checklist.

13. On this PRESTART CHECKLIST for a stationary engine, one of the first considerations is whether or not this is a .engine.

New

14. To be able to start the engine without damaging it and to be able to..the engine in an emergency, you must know the location of all valves, piping, and controls.

Stop

15.To prevent an accidental startup, the ignition switch is turned ..

Off

16.If the engine has been worked on, or if it is new, pieces of weld metal or other obstructions may be lying in the fuel line.

If the fuel line is .the engine cant start.Blocked / Plugged17.When engines are new or have been worked on, the is checked for blocking material.

Fuel line

18.There is less strain on the engine if it is started when it (is / is not) coupled to the load.

Is not

19.For example, if the engine is used as a pump driver, the pump should be (Unloaded from / Loaded to) the engine.

Unloaded from

20.Unload the driven unit, following .instructions.

Manufacturers

21.For proper engine operation, the lubricating system valves are adjusted to deliver oil to the engine, and the engine oil reservoir should be filled.

If water is present in the engine crankcase, the crankcase is.., the water source found, and necessary repairs made.

Drained

22.The oil strainer and oil filters are., if necessary.

Cleaned

23.The governor and throttle are checked.The throttle must move freely to give rapid control to the engines.

Speed

24.The cooling system must be filled, and heat exchangers filled with coolant.

When the cooling system is full, check carefully for any coolant . from the system.

Leaking

25.The cooling water should remain turned on if the cooling system is an (Open / Recirculating) system.

Open

26.On a new engine, the oil lines are empty.Since the oil pump is run by engine crankshaft, the will not fill them until the engine.

Starts27.Thus, before starting the engine the pump must be operated..until the system is full, and until the engine is up to speed.

Manually / By hand

28.Large industrial engines may be equipped with motor driven lubricating pumps.

Then it is not necessary to operate a motor driven lubricating pump by.before starting the engine.

Hand

29.On engines equipped with separate lubricators, the reservoir oil must be checked and .added if necessary.

Oil / Lubricant

30.The engine should be turned manually (cranked) through one complete revolution to make sure that all parts move freely.

Fuel valves areand ignition switches are (On / Off) while the engine is being cranked.

Closed, Off

31.If the engine is equipped with an electric starting motor, it is not necessary to turn the engine over manually.Movement can be checked by simply engaging the .. motor for a few seconds.

Starting

32.Some engines are started by forcing air into the cylinders.

The air forces the.to move.

Pistons

33.When the engine has an air motor starter, the air valves must be (Open / Closed) so that the air can turn the engine over.

Open

34.Moisture may be present in the starting motors air tank.

Drains to this tank are opened to force out any.in the tank.

Moisture /Water

35.In this way, the air entering the cylinder is ..

Dry

36.All fuel supply valves except the one which lets gas into the header line should now be ..

Opened

37.With this header line valve closed, no fuel can enter the..

Cylinder

38.In engines using natural gas, the gas pressure at the header should be checked.When gas pressure is high enough for engine operation, the over speed trip switch may be set to ..

On

39.Other automatic safety devices may also be set to.

On

Engine Starting Procedures

The engine is now ready to be started. Starting procedures vary from manufacturer to manufacturer and for each particular installation.

The starting procedure given here is intended for a spark ignition engine using natural gas as fuel.

40.To be sure that all auxiliary systems of the engine and the driven unit are ready for., the items listed on the prestart checklist should be accomplished.

Operation

41.If one engine has been operated recently it may have some unburned gas left in it from the previous operation. This unburned gas can explode in the intake manifold or in the muffler.

It must be.before starting the engine.

Purged / Removed42.If the engine has a magneto ignition system, it is wise to ground the magneto to prevent sparking, which can cause gases to..in the intake manifold or muffler.

Explode43.If the engine is equipped with an air-motor starter, the air valve is now opened.If it is equipped with an electric starting motor, the starter is .to turn the engine over.

Engaged

44.The engine should be allowed to make 10-15 revolutions to purge any unburned gases from the intake or exhaust system.

When the engine has been purged, it should be stopped; the oil pressure safety switch and the..switch should be turned ON.

Ignition

45.As soon as the ignition switch is turned ON, then the gas valve in the header line should be opened to admit.to the header line.

The air valve remains open or the electric starting motor is engaged until the .begins to fire.

Fuel, Engine

46.If the engine fails to start before the fuel gage registers 5 psi pressure the engine is shut down immediately to find and .the trouble.

Fix / Correct

47.The engine is allowed to warm up to operating temperature before it is loaded.

The engine is warmed up at reduced speeds and without load until the temperature gage on the .shows that the temperature is within the operating range.

Instrument panel

48.If the oil pressure gage shows no pressure within a few seconds after the engine is started the engine is immediately to prevent serious damage from having no lubricant.

Stopped / Shut down

49.When an engine is being started for the first time, it should be run for only 10-15 minutes and then stopped for an inspection to check for overheating.

Inspection covers are removed, and the crankshaft and bearings are touched to see that they are not getting too

Hot

50.Some of the lubricating oil may have flowed into parts of the system which were empty when oil was first put in.

This flow the amount of oil in the reservoir.

Decreases

51.If the oil level indicator shows a low oil level, the oil is .

Added

52.After inspection, addition of oil, and replacement of inspection covers, the engine is ready to operate.

The oil pressure safety switch and the ignition switch should be turned on again, and the .mechanism turned on again.

Starting

53.New engines require very little breaking in, because the manufacturer breaks them in at the factory.

The new engine needs to be run for a few hours at (Partial / Full) speeds before it is fully loaded.

Partial

54.Before fully loading the engine, check to see that lubricant is reaching all parts.

If the lubricating system is functioning, the engine is ready for load.

Full

55.The engine can now be fully loaded to the manufacturers rated HP.

You watch the indicators and the controls to make sure that no..develops.

Trouble / Problem

Procedures for Stopping56.The stopping procedures for a stationary spark ignition engine are simple.

But the right sequence of steps must be followed to. raisfiring.

Prevent

Preventive Maintenance

Engine operating efficiency can be maintained for longer periods of time by performing periodic engine checks at least once every day.

57.The best source of information about engine operation is the Daily log sheet which is prepared by the running the engine.

Operator

58.The daily log sheet also gives information about maintenance performed on the engine.

The operator who makes out his Daily Log Sheet carefully gives a complete history of the .

Engine

59.An engine needs little attention when it is new, but it must be checked periodically to keep it operating.Efficiently / Properly

60.The operator should check often enough to keep the fuel pressure .enough for efficient operation.

High / Constant

61.The operator must also check the air pressure in a 2-cycle engine to be sure that enough..is getting into the engine.

Air

62.Oil levels are checked to be sure that there is enough oil to reach all moving parts.

The temperature of oil is checked periodically to assure that moving parts are properly..Lubricated

63.Proper lubrication prevents ..and overheating.

Friction / Wear

64.Governors must be lubricated properly and must have enough oil for hydraulic units to maintain proper control of the engines ..

Speed65.Cooling system temperature show how well the engine is working.

These temperatures should be checked frequently to see that the engine is not getting tooHot

66.To assure continuous engine operation without malfunctions, the operator should make the checks shown on the Daily Log Sheet and show them in the .space when he makes the check.

Hour / Time

Daily and Weekly Preventive Maintenance Checks

Preventive maintenance checks should be made following the manufacturers instructions. Some inspections, like those on the Daily Log Sheet, should be made more than once a day. Other inspections need to be made only once a day or once a week.

67.Water level in the cooling system and ..level in the oil reservoir need to be checked daily.

Oil

68.Oil filter handles on cleanable filters or strainers should be turned at least every 4 hours.

All other filters should be checked at least once every week to see if they need to be .

Cleaned / Changed

69.In diesel engines, the fuel-gas injector valves must be lubricated at least once a week with a small amount of grease to be sure that they can admit the proper amount of .to the engine.

Fuel / Gas

70.Daily and weekly lubrication of valve rocker arms, rocker arm shafts, and connecting linkage is needed to be sure of proper .Operation / Action

71.All lines in the system should be checked at least once every day to make sure there are no losses of fuel, oil, water, or air as a result of .in the lines.

Leaks / Holes / Obstructions

Monthly Preventive Maintenance Checks

72.Some parts of the engine can function longer than others without special attention.

The air cleaner can go for as long as a month under normal conditions without having to be .

Cleaned / Changed

73.Oil condition should be checked every month to see if the strainer or the .should be cleaned or changed.

Filters

74.The fuel-gas injector valve may begin to erode by the end of a month of operation.

To keep these-injector valve nozzles from causing inaccurate fuel injections, they should be .every month.

Checked

75.Unless pure water is used, or rust and scale inhibitors are added to the cooling water, rust and scale form quickly in the engine water jacket.

When no inhibitors are used, the engine water jackets should be checked for..and..formation at least once a month.Rust, Scale

76.Once every month, the whole ignition system should be checked to be sure it gives a hot enough.to ignite the fuel.

Spark

77.Once an engine has been installed, its operation is pretty much up to the operator and the preventive maintenance .he makes.

Checks / Inspections

78.The periodic inspections made by the operator are the basis for a companys preventive maintenance plan.

The operator should never..to make them.

Forget / Fail

79.Operating manuals from manufacturers usually outline general maintenance guides for their engines.

These general maintenance guides should be combined with the procedures of your company and with the Daily Log Sheet for efficient operation of each.

EngineReview and Summary

80.To start a spark ignition engine using gas as a fuel:

a.The fuel valves are open, except the valve which lets gas into the .line

Header

b.The starting motor or air motor is .

Engaged

c.Then the ..is turned on immediately.

Ignition switch

d.Gas is admitted to the header line by . the valve.

Openinge.When the engine begins to fire, disengage the

Starting motor

81.To stop the same engine:

a.Cut off the ..supply.Fuel

b.Fuel is cut off by .the main fuel valve.

Closing

c.To burn any fuel left in the engine, the ignition should be leftafter the fuel is cut off.

ON

d.After the engine has stopped, turn off the ..

Ignition switch