All Small Engines Everywhere

By Jeff T. Murray

This tech - manual; hand guide is intended to assist anyone; anywhere with two; and four cycle small engine maintenance; and repair; along with single and four cylinder diesel engines and nitro-methane hobby craft engines; as well.

• Language: English
• Publisher: Newman Springs Publishing, Inc.
• Release date: May 23, 2022
• ISBN: 9781638813989

Book preview

Introduction

The information in this book is basically written in two parts. First, on two-cycle small engines and then on four-cycle small engines, then information on diesel and nitromethane small engines.

This book is intended to help and assist the homeowner, small and large, commercial or industrial use, and the general public that are comfortable and familiar with working on their own equipment.

Some mechanical or electrical problems that may be out of bounds for repair can be deferred if it is warranted. At a glance to the engine to be worked on, determine its classification or type. Then proceed to look up the proper chapter needed. Additional information is also listed after for referencing.

This manual is to assist anyone who is engaged with this type of work and all of the problems with it. It is great to contribute after being ramrodded, railroaded, and then not hired in my career field for the last forty years. The best positions were with the greatest people.

The illustrations entered and listed in this texted manual are all custom drawing or atone in order to not copy, duplicate, or infringe of any one person, persons, or manufacturer’s engines, prints, parts, or products that are or have been sold on the market or is available to the public.

Safe Practice Note

It is important that whenever working on or around small engines and equipment that the use of safety equipment is recommended, such as googles for grinding, ear plugs for loud power tools, and protective gloves to keep hands from being injured. Do not smoke or store at any time. Complete all tool usage with care. Pull instead of pushing when wrenching or ratcheting. Make all idle speed and fuel mixture adjustments with a running engine. All information here in this book was carefully compiled and true. I, the author, and the publishers cannot accept, assume, or be held liable or responsible for any property damage, loss, personal injury, or death caused by any mistakes, errors, poor judgment, misuse, or misinterpreted or left out or omitted from this information, data provided, and given.

Application Requirements

With the use of this hand guide, it is important and imperative to have all of the proper hand tools required to complete any of the following procedures or tasks listed that may be encountered when working on many of various types of small engines and the associated equipment

Power or pneumatic tools are not usually necessary, unless a higher volume of progress is expected in a very short amount of time. At the same time, it is best to be prepared for instances where the hardware cannot be removed or breaks or rounds off during an important disassembly. Grinding, cutting, sawing, or drilling the hard hardware is some of the best ways to save a project because hardware is expendable and should not hold up or stand in the way of any engine repairs, replacements, or rebuilds.

Identification

To identify the type of a small engine, look to see if there is a stamped plate, sticker, or nomenclature mounted with the typical specifications on the engine block or flywheel cover.

This information should give the brand, model, and a list of numbers with letters that are used to classify the engine and most important of all to correctly order and receive the right replacement parts. Become familiar with the location of and acquainted to the information on this emblem, it is about the only lifeline that comes with an engine. If this information is missing and the time comes to order new parts, then the engine can be taken to the brand dealership or parts distributor for the equipment to order and obtain the correct new parts that are needed. The engine’s design and configuration can assist ordering parts.

Performance

When the use of any type of a small engine is needed to run a piece of equipment for any purpose, the engine should always start fairly easy and run with strong power and consistency. Having all of the safety ignition switching on and closed with fresh fuel and the engine as choked on the first two to four cranking revolutions, the engine should start and be running. The choke is then returned to the open position and the engine is throttled up to engage the equipment, load, and/or implement. At the proper amount of throttle a two-cycle engine should hold a steady engine RPM as it is introduced to a load and not bog down and handle the load well within reason. A four-cycle engine should throttle up and hold steady as the governor handles the load.

All small engines everywhere

(JTM Writing & Machine Works)

One of first two-cycle engines.

Hit-and-miss.

Chapter 1

Simple Maintenance

For the general attention of your equipment’s small engine. This is a primary listing of checks and inspections, replacements, and adjustments and procedures for periodic maintenance and accurate care of your small engine.

The listing can be started at any point of the context for convenience or a priority to correct and maintain only a few items or to complete the whole listing for the small engine that is at hand. The listing can begin with checking and servicing the spark plug or spark plugs (if the engine has more than one cylinder). Remove the spark plug to inspect for how well a spark plug may be operating and for its serviceability and condition. Inspect both insulators on the top and bottom for chipping or cracking. Check for an amount of carbon buildup and wear on the electrode and bridge of the spark plug. Replace damaged, carbonized over or oil-soaked spark plugs. A spark plug with normal wear and some carbon buildup can be cleaned, tested, and reconditioned for reuse to a limit. Use a small wire brush with brake cleaning fluid to remove oil, carbon, and debris from inside of the insulator tip, electrode, and bridge area. Then check for the amount of wear of the electrode underneath the bridge.

A very rounded electrode end will indicate high usage. The end of the electrode can be sanded or filed flat to regain the sharp, crispness of the ignition spark. The bridge to the electrode makes up the plug gap. The plug gap should be kept to the manufacturer’s specifications. To check a plug gap, a feeler gauge is used to measure the distance to precisely adjust the gap in. To adjust the gap, pry in between the bridge, and the electrode to widen the gap and tap the bridge on a hard surface to close the gap. If the specifications for a certain plug size or heat range is not available, a common gap setting for smaller two-cycle engines is usually at least 0.025 in. but not any larger than 0.030 in. For larger two-cycle and four-cycle small engines, the gap settings will start out at 0.025 in. and increase to 0.030 in. and 0.035 in. Clean and check used spark plugs and threads before installing them. When inspecting the actual performance of a spark plug with a visual check of the spark that the plug makes, always directly have the plug grounded to the engine and have no open fuel close to the spark.

With the ignition on and the plug lead connected to the plug, crank the engine to view the strength of the spark. A thin to a thick blue or white spark is best. A yellow or orange spark would indicate a power loss to replace the plug, then also test a new plug to check the ignition. Spark plugs can also wear and build resistance. A plug may show what looks like a good spark but then fails to fire under compression very shortly after being installed and begins to miss or skip. The resistance can also be measured with an ohm meter and be compared with a new plug, if desired. Spark plugs are also a good indicator of how well an engine is running. Next is checking and servicing the air filter. Remove and inspect the air filter.

With most types of cartridge filters are replaced once the element fills up and does not pass light. Replace a damaged or punctured filter. Use a flashlight or indirect sun light to check the condition of a filter in question. Some air filters can be cleaned for reuse. Foam rubber and similar element or media materials can be washed with a clean fuel or brake cleaner, dried, and a light amount of clean oil is applied to them before they are reinstalled. Cloth-fiber-type air filters can also be washed and dried in the same way and reused but do not need to be lubricated. Next is checking and servicing the fuel filter. A fuel flow check is one of the quickest ways to determine the status of a fuel filter. The best way to check a fuel filter is to see how easily air may pass through it. Partial to fully restricted filters are replaced. Some types of filters can be backwashed or backflushed and reused again to a limit.

Also replace any damaged or ruptured fuel filters with exterior cracks or visual internal punctures on see-through-type fuel filters that are installed on most of the larger lawn and garden equipment. Fuel filters that are located inside of the fuel tank on the smaller lawn and garden equipment that are on the end of the fuel line or in a stationary fuel fitting, on the bottom of the fuel tank can be back flushed also as needed. Next is checking the condition of the fuel. Use a flashlight to inspect for contaminants, water, or particles accumulated on the floor and inside of the fuel tank. Flush to clean a fuel tank and always use fresh fuel for both two- and four-cycle small engines.

Inspecting the condition of the engine pull-starter and power implement. Damaged or frayed starter pull cords are replaced as needed. Also bad starter pullies and broken recoil springs are replaced as they become defective. The length of the replacement pull cord should not exceed four turns of the starter pulley when it recoils or returns. Check the implement that it is mounted and installed properly and is serviceable, sharp, loaded, and ready.

Engine stopped: Two-cycle simple maintenance

Listing for simple maintenance for two-cycle small engines:

Check, clean, or change spark plug or plugs.

Check/regap air filter.

Cover fuel filter.

Fuel unserviceable pull-start cord.

Check for proper fuel flow from the fuel tank to the carburetor. (Visual or in fuel line.) Present plug condition (see chart) and loose hardware, such as nuts, bolts, screws, washers, or rivets. Tighten to specifications. Keep clean and clear of carbon deposits.

Clean clogged air fins, shrouds, louver, and flywheel fins. Keep clean and free of dirt and debris that could lodge inside these areas. Check for proper or adequate ignition with no open fuel present! Conduct a spark check with a spark indicator instrument or a new spark plug. Drawing of plug chart on page 24.

Engine running in a well-ventilated area

Adjust. Idle speed should be made with equipment type of transmission/clutch, direction controls in neutral, and the throttle is at the lowest position (before the engine shuts off.) The idle speed should be high enough to keep the engine running at a low steady idle but stay well above stalling. The correct RPM range for almost all engines is 700–800 RPM.

Adjust. Air-fuel mixture should not need to be adjusted, unless the float setting has been changing or there may be a restriction within the carburetor. The adjustment screw is usually located on the bottom of the fuel bowl under the carburetor. On smaller applications, it will be on the side. A high and low screw or one screw will be in line with the idle screw on the carburetor. Slowly back the screw out one quarter turn. Then in until the RPM even up, smooth.

With the engine idling at this time, the exhaust should be minimal with smoke or emissions. The low idle RPM should be even and optimally consistent. If an adjustment is needed, back the screw out slightly without increasing the smoke or emissions. If the carburetor also has a venting airscrew, adjust by turning this screw out only at or about less than an eighth of a turn at a time. If this does not help, both adjustment screws can be reseated and then turned back out exactly three half-turns. This is a relatively close setting to start over from if needed. If this is no help, then the carburetor may have other problems and may need to be rebuilt with a carburetor rebuild kit for the carburetor in question. Under idle or high RPM with a load, the engine should have a clear sound of performance with a good and steady rhythm.

Simple maintenance listing for four-cycle small engines

Check, clean, or change the following:

spark plug or plugs

air filter

fuel filter

Crankcase oil and filter, when applicable.

Check, change, or correct the following:

present spark plug condition (see chart)

for loose or missing hardware (replace and tighten all hardware to specs)

for dirty or obstructed engine air fins, covers, shrouds, cowlings, and air directional passageways (keep them clean and open for air- and water-cooled engines)

fuel delivery (check and ensure for an unrestricted fuel flow from the fuel tank to the carburetor)

proper to adequate ignition (the ignition can quickly be appraised with a spark check by using an ignition indicator or a new spark plug)

Engine running in a well-ventilated area

Adjust the idle speed. Place the drive control in neutral with the transmission disengaged. Place the throttle handle at the lowest setting. As needed, the idle screw is set to maintain a low smooth, even idle, but not over speed. Set to 700–800 RPM. Check the fuel-air mixture. It’s similar to a two-cycle engine’s emissions. Only as needed, for an indication of too rich emissions, begin to adjust the fuel by turning the mixture screw in only an 1/8" of a turn at a time. This should only be a small adjustment. Return the adjustment if no correction noted. The setting would correct if the mixture was a problem.

Turning this screw out increases fuel flow. Too much gives a sluggish throttle response. Too little will cause it to stall and give white smoke when throttled up. If it has to start over where adjustments get out of hand, each screw is backed out only three half-turns from being seated. This is close enough to start over to.

Check and adjust. The governor maintains the idle down and controls the throttle plate in the carburetor, only on engines that are equipped with a governor system. If the governor is correctly adjusted, it will compensate quickly to accommodate a load without stalling and can return to a steady idle when unloaded. If a load or a demand is put to a governor running to or at operating speed and the engine box down, the governor may not be adjusted high enough. If it over speeds on idle, it may be adjusted too high. If a governor oscillates on idle up to midrange speed, the fuel mixture and air elevation camp screws may not be adjusted correctly. The governor linkage and controls may be worn in vital sections, affecting the governor’s reaction time.

Chapter 2

Two-Cycle Engine (Part 1)

Tuning a two-cycle small engine

A tune-up for a small two-cycle engine covers replacing, servicing, or cleaning the spark plugs and ignition points, if applicable. Check ignition timing and all the moving associated parts for wear that may warrant replacement. Then check to see if any carburetor adjustments are needed for idle and the high or the low side of the carburetor after a tune-up. Compression is also important to check. Periodic tune-ups ensure better overall performance, keeping fuel usage low, holding correct operating temperatures, and minimizing wear to extend the life of the engine. An engine will start easier and can complete more work with the equipment and lessen the chances for early maintenance.

It may be easiest to start a tune-up with inspecting the spark plugs first to see what condition they are in. This can indicate if a problem exists and will give a good idea of an engine’s present condition. The following plug chart and descriptions of the plugs should cover most cases encountered with a tune-up. Viewing the threaded electrode area, common wear. A correct heat range will show a plug with very few deposits of brown or tan color in appearance and low wear of a center electrode. A plug can be filed flat on the end of the electrode, then regapped to specs and reused unless the known age of the plug is excessive and should be replaced. The same for the other conditions.

Ashed/rust deposit—These appearances are from fuel and oil additive buildup. This is not a concerned condition because the plug can be gapped and cleaned for reuse.

Speed glazing—An incorrect heat range has a white, shiny, or overheated insulator. This can show the plug is running too hot. Also check for manifold leaks, ignition timing, and the fuel running too lean. The next colder heat range may be used. The ignition timing could be too far advanced.

Oil covered—Has an oily sludge covered plug electrode. This can be from a dirty air filter, mixing oil/fuel too rich. A restricted exhaust muffler, ports, or muffler screen. Also worn piston/rings or cylinder. A next higher heat range may help temporarily. This may indicate the engine will need rebuilding or replacements eventually. This plug may be cleaned and tested for reuse.

Detonated—The insulator on the electrode will be broken or chipped. This is from too much carbon buildup inside the cylinder head, too lean of mixture for air/fuel, ignition timing too far advanced or poor/low fuel quality, octane wise. Replace this plug.

Carbon covered—Has a black, powdery, dry amount of buildup on the electrode area. This can be from retarded timing worn points, fuel too rich, low compression, stuck choke, dirty air filter, or cracked plug leads. This plug may be cleaned and gapped for reuse. Spark plugs can also have other conditions like being fouled out with other variations of fuel or oil catalysts or with additives. They could enter the cylinder while the engine is in operation, and if any pieces from inside of the cylinder area come loose, it will most certainly hit the plug and bridge the electrode. This may be audible the moment it happens. Any debris stuck in the electrode gap of the spark plug would cause it to miss fire or stall.

When gapping a plug, a wire gauge is best to use aside from a feeler gauge. Set the gauge to the correct size digit or plug gap specification. Place the digit into the gap. Bend the bridge in or out to adjust the gap to the exact size and thickness of the gauge digit. Tap lightly on a hard surface to bend the electrode into correct a wide bridge gap. A plug should only be regapped three or four times, then be replaced the next time a tune-up is needed.

Small Engine, Two-Cycle Spark Plug Condition Identification Chart

A compression check can be taken next with having the plugs out of the cylinder head.

There are a couple different types of testing gauges that are used to quickly check a cylinder’s compression. One test gauge threads into spark plug port, the other gauge has a rubber tip to hold against the spark plug port. Mount the gauge to the cylinders to test. Disconnect all other plug leads and crank the engine four times to see the highest reading. A wet, vs a dry test can also be done on each cylinder in question. This can isolate and identify major or marginal wear from minimal wear. Compression testing is an accurate way of diagnosing a power loss if any problems are experienced or suspected at any time.

The most compression that a used engine may have should be between 90–100 PSI. A new engine can be above 100 PSI an engine below 80 PSI could be rebuilt. Pour a teaspoon of clean engine oil down the spark plug port. Then test the cylinders again. If the compression improves 10–20 PSI, then the rings and/or the cylinder may be worn, and the piston may show some wear on the skirt, sides, and the ring groove areas. If the compression does not improve, then there could be a hole burned through the top of the piston or the piston could be fractured or may have hair line crack. In this case, if it is decided to rebuild the engine, refer to chapter 3 for two-cycle engine rebuilding, assemblies, and disassembly with other problem indications also listed. There are some two-cycle small engines that have a reed plate in between the carburetor and the intake port to the cylinder. The condition of this reed plate can affect engine performance. Inspect and gap to 0.010 in. when conducting an ignition check. It involves cranking the engine over, as in taking a compression reading. All that is needed is a clip-on type of tester for checking ignition or an insulated, a gap-adjusting-type tester or a new plug that has its adjusting bridge shortened is good for testing ignition too. Then make sure there is no exposed fuel at or near the test and outlets or fuel valves are turned off.

Then place the tester in position. Attach the engine plug led to the top or tip of the tester. Then clip or secure the base of the tester to the engine body or frame to conduct the voltage current. Then isolate the engine away from oneself. Keep the spark plug port clear to allow full free movement to gain the momentum needed to generate a detectable spark. Make sure that the ignition switch is on, if applicable.

Observe the tester gap when cranking the engine over with a pull rope or starter. The spark should be visible in direct daylight. The spark should be a blue-white in color and consistently spark each time the piston reaches the top of the cylinder. One or two times should be adequate for checking the ignition. A thick blue-white spark indicates a strong ignition. An orange to a light-red spark would show a weak ignition. This can be caused by a few different reasons. The ignition points may need cleaning, gapping, or replacing. There may also be loose or bad wiring that can be burned or open inside. This can slow or hinder the electrical current or flow, causing a weakened ignition spark.

If there is a problem, see troubleshooting the two-cycle small engines for remedies, methods, and procedures. Place the plug back into the plug port to keep the cylinder clean. When completing, changing, or cleaning and regapping the points and condenser, it is usually the hardest part of making a full tune-up of most models of two-cycle small engines because it may involve a small amount of engine disassembling to access the point set unless the ignition parts are located under a side cover, making them more accessible. On most earlier models, the points are located under the flywheel. They ride on a single cam lobe that is ground or machined onto the end of the crankshaft.

The points that mount on the outside of the engine with a cover over them are usually operated with a tiny non-metallic push rod against a cam relief or raised lobe. For safety, the fuel should be drained from the tank and carburetor or engine before any disassembly is started. Store the fuel in a fuel container if the fuel is reusable. If not, then contain and dispose of fuel properly. To save time, before removing the parts and a cover, it’s needed to determine if an engine actually has a set of ignition points under a flywheel or not. To identify if the ignition coil has a solid-state electronic ignition unit, check for if there is no wiring connecting the ignition coil to underneath the flywheel. If not, the engine won’t need a contactor point adjustment. Only remove a flywheel if it is certain the points need servicing or a rebuild. A coil connecting underneath the flywheel will show that there is a set of points located there. Have the pull-starter cover removed. Keep all hardware—nuts, bolts, and washers—together in a bag secured with associated parts.

It is suggested to wear eye protection for the next procedures. Pulling and removing the flywheel is next. Select to obtain and use a gear puller or of this case. A pulley puller is about the size tool if it’s a small flywheel that’s needed to pull. At this time, it is also suggested to use common safety practices at all times when doing and completing these types of methods and procedures with safe use of correct tools. For tools needed, a listing of metric and English sizes from 22 mm. to 4.5 mm. and from 1 in. to ¼ in. Cheaper tools will still do but may not have all of the quality as more expensive tools.

To access a set of points that are under a flywheel, secure the flywheel properly, so it cannot turn in either direction. Loosen the flywheel nut and back it off to leave at lease a space of ⅛ in. to 1/15 in. in between the nut and the flywheel washer. Then place the puller across the flywheel and on the center of the bolt above the nut on the shaft. Adjust the puller laws to evenly hook the outside bottom of the flywheel. Begin to tighten the center bolt of the puller down snug. Hold the flywheel secure, then firmly tighten the puller bolt against the center of the shaft. Then strike the bolt head firmly to dislodge the flywheel from the crankshaft. Occasionally some models with a thin flywheel will break in half. Care with attention must be used to avoid injury or damage if the situation is encountered. A flywheel can be repaired or replaced. As the flywheel separates from the crankshaft, remove the flywheel puller and the shaft nut and washer. Remove the flywheel from the crankshaft and inspect both key and keyways for wear and condition of the parts. Parts with a worn key can be spray welded and machined back into the shaft or change out the part. Any keyway keys marked or cut sideways should be changed. Upon removing the cover from the ignition contactor points, inspect for the following list of items that are most important to a set of points.

For getting the most use and performance, see if the lubrication felt or the soft piece that rides the points came has been kept moist. It lessens for wear when the engine runs. Then check the points tab that also rides the points came for wear. If they are worn with more than 25 percent, then they should be replaced with a new set of points. If the points are spiked on one side or the other, this may indicate a problem with the condenser. If the spike points up from the base contactor and into the arm side of the contactor, then the capacitance is too high or the condenser may be overrated for the application or the engine. If the spike is opposite, the condense may be shorting or grounding out and should be replaced.

Keep the points area clean and use a parts spray cleaner to remove any oil films or debris, then check the present point gap setting. Turn the crankshaft to place the ignition points at their widest gap. Use a 0.020 in. feeler gauge digit to check and compare the present point gap setting to 0.20 in. is the correct setting for both two- and four-cycle small engines that have old style ignition points. It can also be summed up how an engine was running by the setting that the points are at. Inspect the point contacts are not crusted or spiked. Then clean the contacts slightly with fine sandpaper or emery cloth. Wipe the contacts once more to remove any particles. Then check the gap. If it’s too wide, the engine fires too soon. If the gap is too close or tight, the engine fires too late. With a gap set to 0.020 in., the engine fires at the correct time.

Inspect the ignition points for wear and serviceability. Check the length of the indexing post that is on the breaker, arm side of the points. If it is a fourth of the way worn down from its original size, the ignition points should be replaced together with a new condenser. If the contacts are pitted or spiked, the points should also be replaced. To adjust a set of ignition points for a new or a used set, place or keep the crankshaft positioned to index or lift the ignition points at their widest point as the points set sits mounted to the engine block. Place the 0.020 in. feeler gauge digit in between the contactor points. Then loosen the points pivot hold-down screw enough to pivot the points. Pivot the points and lightly lock the hold-down screw when the setting is reached. Remove the digit from the points contacts. Then turn the crankshaft around once or twice and stop at the point gap index. The gap will check at 0.20 in. if its correct. Then tighten the mounting screw. If the setting is not correct, repeat the adjustment until it is correct.

When changing and installing a new set of points, check to make sure that the parts are correct for the engine when purchasing a set of points. Read through and become familiar with all of the steps and instructions that should come with a new set of ignition points and a condenser before installing the parts. Some ignition points sets come with a special lubricant for the points cam. It is important to apply this grease to the lubricating felt or wick and cam after completing points set installation. Some point sets may also come with a special contact coating to preserve them. Upon correctly completing new points and condenser installation, check that all the hardware and wire connections are tight. When installing the points cover, some models use a sealant that can be applied if needed. The flywheel and key are reinstalled next. Place the flywheel keyway facing up sideways. Place the key in the keyway about midposition. Slide the lined-up flywheel onto the crankshaft to see the key to stay in place and the flywheel sets flush as it was installed. Then install the pressure washer and flywheel nut. Snug the nut down in place and then turn the engine to check for a clear rotation. Secure the flywheel from turning. Then torque the flywheel nut to 20–25 ft.-lbs. Then reassemble the engine the rest of the way to complete the assembly. Prep to test run the engine when set. Allow the engine to warm up. Then begin to tune the carburetor for 700–800 RPM to idle, then the high and low sides to full performance.

This is a short listing of preferred settings or specifications for most two-cycle engines. These settings and amounts will create for good- to top-quality performance for these makes and models that have specified plug and point gaps. Gap spark plugs, 0.030–0.035 thousands of an inch. Gap ignition points 0.020 thousands of an inch. The type of plug should be correctly for a two-cycle application because of its heat range and is firing with every stroke of the piston under constant demand.

When shopping for parts, be sure that the plugs and points are matched and are exactly for the make, models, and size engine that is being worked on. The cylinder compression for any two-cycle small engine should be just above 100 PSI, if new. When an engine is tested with a compression gauge, a reading at around 100 PSI is expected. With lower readings, engine’s performance and start abilities begin to diminish.

Troubleshooting two-cycle engines, one or two cylinders

This is a listing for two-cycle small engines with one or two cylinders that are hard starting or do not start. The listing covers the main important items of their locations on a small engine. Become acquainted with the list to troubleshoot more effectively. The ignition, compression, and fuel systems are most important to a running engine aside from engine timing. Continue to use good safety practices and use protective wear as suggested. The ignition system can be checked first to begin the listing.

A spark check will quickly indicate what to check next. Have the engine prepared to crank. Turn on or close any start switches and ensure any type of shut-off switches are open. Remove the spark plug from the cylinder being tested. Place an ignition tester or a good sparkplug on the ignition lead and ground the tester or plug against the cylinder head. Crank the engine to view the ignition spark. If the spark is thick or thin blue-white arc, the ignition is best. An orange-yellow spark is a weak ignition. No spark at all should be tested several times with both indicators to confirm the ignition. With a good spark, an engine problem should be in one of the next two-engine systems listed.

If a weak spark or no spark is viewed, begin to check the ignition system in reverse from the spark plug back into the engine. Attempt a spark check with a third testing entity. Then check that the plug lead connecter and plug tension lead wire are connected to the ignition coil. Then the pull-start cover or flywheel cover is removed to check the ignition coil. The ignition coil is visually checked for any physical damage from internally shorting or disconnected wiring. The ignition coil is then checked electrically with a small handheld multimeter. The meter is set to check resistance continuity. The coil windings are checked for open or a shorted circuit by touching one meter led to the outside metal base of the coil and the other meter led to the coil windings. If the coil is good, the meter will show open or no continuity. If the coil is bad, it will show connected. If the windings show open but not shorted, the coil is also bad and must be replaced as well. With a good coil check, recheck the ignition. If still no ignition, then begin to check the ignition points and condenser, if the engine is so equipped. The flywheel is removed to check, adjust, or change the ignition parts. These parts are also checked with a meter for opens or shorts. The points should be changed if they are shorted and have a high amount of wear. The condenser is replaced if it shows open or will not buildup voltage with just the meter. Also check and replace bent, cut, or a bad flywheel key, as needed in this area. Readjust points to 0.020 in. Reinstall and torque the flywheel nut to 25 ft.-lbs.

For fully encased electronic ignition systems with sealed components, all of the wonderful parts that make up the induction circuit to the ignition coil are all now housed or encapsulated inside of the ignition coil. Other than