By examining the spark plug insulator color, an experienced personal watercraft engine tuner can determine valuable information about the engines overall operating condition. If you notice any black, dry soot on the spark plug, this is a sign of carbon fouling, which means your engine has been running too rich, and you should visit a mechanic to figure out the cause. This condition is ideal, the spark plug and engine airfuel mixture are operating properly. Plugs change colors and the different colors can explain such things as if the engine is running too hot or if the engine is worn.
The color should be read by looking at the porcelin insulator and compared to the plugs shown on the next few slides. Mar 29, 2019 to read a spark plug, start by checking the color, since an undamaged spark plug will be light grey, or possibly tan. Check for faulty or sticking choke, overly rich fuel mixture, ignition problems, leaking fuel injectors, or spark plug heat range is too cold. But remember better to a bit rich and foul a plug thene to be lean and burn a piston or somthing look for sings on the plug for running too hot, thats the way i did it. Reinstall the clean spark plug and ride the scooter for about 100200m under complete load full throttle, ideally up a hill. The plugs on the right are close to ideal for a 2stroke. When an engine will not start, spark plugs often tell the story. Over time it may wear out and begin to fail eventually requiring a replacement to ensure top performance. Black, carboned spark plug page 3 buggies gone wild. It is also a weekend warrior and meticulously maintained in. Discussion in technical chat started by cobra69, nov 16, 2008. Spark plug porcelain tan half way around and white the. Check for correct application of spark plug heat range too hot, wrong spark plug for engine, cross firing of ignition cables, over advanced timing, lean fuel mixture, defective egr valve, accumulation of combustion chamber deposits, hot spots in the combustion chamber due to poor heat dissipation, improper installation torque applied to spark plug, andor head gasket protrusion into the combustion chamber.
Congratulations, you just did a plug chop looking down the inside of the plug porcelain you are looking for a ring of color or a band about 18to 316 wide. It is important to read spark plugs many times during the tuning process to achieve optimum airfuel mixture. Correct heat range for engine and operating conditions. Spark color to determine ingition coil performance. I am starting the troubleshooting by looking at the ignition system. Black, carboned spark plug i dont know about cart plugs but i thought you were going to a hotter plug and you got a 4 instead of a 6 and you had a 5.
Step 7 of 8strictly aircooled san diego whatever your plugs look like, theyll benefit greatly from a vigorous clean up with a. However, your spark plugs will become either too clean evidenced by a lack of normal color or white when your engine is running significantly lean. Other than installing thermocoupler sensors in the combustion chambers the only real way that you know what is happening inside your engine is to read the spark plugs. Mine are not white, but definatly not black either. If oil was leaking out the spark plug holes, it would be very noisy from compression sneaking out and the plugs would be oil fouled and not white. With you saying that its an amber color i would say that it seems fine.
Symptoms of running lean are overheating, bogging or loss of power, and delay of returning to idle from higher rpms. Try to use a toocold spark plug and you very likely will have to jet for a lean mixture to avoid plug fouling and as you lean an engines airfuel mixture down near the roughly14. While the answer covers this question, the questions really dont line up. I could have the leanrich mixed up from what i was told, spark plugs should be right in the middle, not too light and not too burnt. Look at the spark plug porcelin for the color and condition of it. Oct 15, 2014 diagnosing plug condition cause and effect. Check for problems in your engines cooling, a lean fuel mixture or incorrect ignition timing. Spark plug 5066k for briggs and stratton lawn equipments. By examining the spark plugs insulator color, even a lessthanmechanicallyinclined person can determine valuable information about the engines overall operating condition. Thats what a normal toyota spark plug looks like normal plugs should be brownish tan in color witch means the heat range is right and the engine looks to be running normal.
Im still really bad at telling what color my spark plug should look like, any thoughts on if this is a good color or if its to dark. Your automobile keeps moving on the road because of the constant ignition. White spark plugs are being overheated, usually from a lean fuel mixture. A lean spark plug will have little to no color on the insulator tip. How to read spark plug colors written by atlantic jet sports. Lean airfuel mixtures cause plug tip and cylinder temperatures to increase resulting in preignition, detonation, and possibly serious spark plug and internal engine damage. Being a sunday, thought of a routine check of the bike and started from the battery. Reading spark plugs spark plug tech super street magazine. Drag racing list spark plug reading 101 for gasoline motors. If the color of the ground strap changes too close to the ground straps end, which is above the center electrode, then the heatrange is too cold, meaning that the strap is losing heat too quickly to the base ring, and is not able to burn off deposits until near its end. Misfire is caused by weak or no spark, generally from improper airfuel mixture or low compression.
The best spark plugs in the world and why duration. The spark plug tip will bear witness to what is happening inside the engine. An examination, or reading of the characteristic colors and markings on the firing end of the spark plug can indicate conditions within the running engine. Checking one or all of your spark plugs will give you a quick read of your engines health with little effort. Basically the plug color is telling you the combustion chamber temperature at the time you shut the engine down.
I had put this out in another question a while back. Motomojo spark plugs what they say about your engine. Plug colors tell the mechanic how the engine is running and can be very important. Spark plug color is only accurate when checked after a high speed run, engine turned off at max rpm, and craft glided in with engine still off. How to check your vw bug spark plugs strictly aircooled vw. If it fires for a second or two the spark is fine and you know the carbs and possibly a fuel pump is not delivering gas. I could have the lean rich mixed up from what i was told, spark plugs should be right in the middle, not too light and not too burnt. As the spark plug can be removed for inspection, the effects of combustion on the plug can be examined. Plug heat range can have a large effect on this process. Appearance firing tip is damp with gasoline, usually the odor of fuel is present on the spark plug. Ignition system problems causing a weak or intermittent spark.
How to check your spark plug for the correct carburetor. Mar 23, 2015 im still really bad at telling what color my spark plug should look like, any thoughts on if this is a good color or if its to dark. Reading spark plugs by mike chilando alkydigger technical. There are three main parts of the plug you should be examining. Spark plugs and what they say from engineering of cixi. A low compression engine running at a steady state with a constant fuel supply wont quench even a spark plug with a yellow spark. A normal spark plug will have brown or grayishtan deposits on the side electrode. This is the correct color a spark plug should be and it tells the mechanic everything is fine with the engine. So, you may well understand the importance of this device in keeping the engine running. All resistance values through the ignition system are per spec. Now, ive got a ngk br9eix iridium spark plug, and looks like its running too lean wtf. But on an automotive engine with a higher compresssion ratio and under transient conditions the yellow spark can get quenched thereby causing a misfire.
If your plug is grey or white, than you know that your engine is running too lean and. The mechanic would install a new properly gapped plug. A wornout plug will have rounded, worn electrodes, creating a wide gap. Heat range ground strap, the ground strap indicates the heatrange of the spark plug. How to diagnose and read the color of your spark plug. Spark plugs wear down over time, but how they wear can tell you a lot about your engine and how its performing. The coil voltage measures about 100 volts and should be volts. What color am i looking for on my plugs to know the motor is running at the right fuel mixture. The top of a new spark plug is covered in white ceramic insulation. Starting with the center electrode, it should be the same color as a new one out of the box. It is an authentic replacement component which is supplied by the original equipment manufacturer for use with briggs and stratton engines commonly installed on lawn and garden equipment.
Feb 23, 2018 your automobile keeps moving on the road because of the constant ignition. Excessive spark advance is even worse in its ability to produce detonation, and when combined. A tan colored plug means that the engine is running normal and the airfuel mixture is correct. Why are my spark plugs white and i have oil leaking out of. If it were running a tad bit leaner, the plug would have more of an tanash color to it. When we buy hotter ngks for race cars we go from a 7 to a 9, are they a difference.
This is why you use a new set of plugs each time you do a plug chop, this ring. When they say a tan color is ideal, that is in reference to a 4stroke engine or a. Feb 16, 2011 dont beat yourself up trying to get a perfectly and evenly colored plug, just make sure that the color that it is is a good color. Is your spark plug black, wet, greasy or dry, dusty or covered in soot, white and crusty or speckled with crystals, i will show you how to read your spark plug and show you what is normal. To do a plug chop, make sure the air filter is clean, warm up the motor, shut it off and install new spark plugs. Btw, the iridium spark plug will ensure better performance than standard spark plugs. The plug is showing me by the deposits on the tip of the electrode and also the deposits right on the edge of the threaded body. Too hot a plug can mimic lean mixture, a cold plug can appear as a rich mixture. If they are burnt very dark then you are running too lean, if they are a very light color you are running too rich. Cabinet combo is the first step in getting your home garage organized project k24 pt. My plugs had a slight brown tent to them after running a race. A white or real light plug color could possibly mean the carbs is too lean.
Jul 27, 2014 hi daniel, i had a shitty spark plug on my polini sport, equivalent with the ngk b9es, the color of the spark plug was chocolate brown. This chart gives you a broad visual of what your spark plugs. The plugs on the left would be ok for a 4stroke, but in a 2stroke they are lean, hot, and dangerous. I talked to a engine builder that gave me a good starting point and went up from there.
Instead, they melt to form a conductive coating and misfire will occur. If the firing end of a spark plug is brown or light gray, the condition can be judged to be good and the spark plug is functioning optimally. When installing a new plug, replace the old one with the same heat range. Causes include worn, fouled, or damaged spark plugs, faulty plug wires, low battery voltage, or a defective coil. If the insulator is white and flaky then your engine is running lean, so check the timing and then adjust your carburettor as well.
The purpose of a spark plug is to deliver the electric current from the ignition system to the internal combustion engine. Spark plugs are generally a brown or grey color, which is caused by normal ignition. And, too high compression, or insufficient engine cooling. By reading the color of the plug you can tell a lot of things about how the engine is running. Clean it by spraying your spark plug with brake cleaner, letting it soak for about 10 minutes, then wiping it with a clean cloth. Running lean can be an indicator for multiple significant problems in your car. Spark plug porcelain tan half way around and white the other.
To read a spark plug, start by checking the color, since an undamaged spark plug will be light grey, or possibly tan. The white porcelain is showing a lean condition at wot, its not too far advanced as the total timing mark or color change is right in the apex of the ground strap curve. Heres what fouled spark plugs look like running too. I think your example is running pretty good, but may be a tad on the rich side. If the plugs are damp with gas, the fuel is present, but was not ignited, there are spark problems. The image below shows a plug off a motorcycle that was running pig rich. Brown to grayishtan color and slight electrode wear.
My car is a 2002 mustang gt 70,000 miles all stock. If the engine is running well and you pull the plugs while riding on the trail and you see a light chocolate brown color all is wellthis would be an average of the throttle position and shut down at that time. Even a couple of minutes can change a clean plug to sooty. Too hot a spark plug, low octane fuel, lean airfuel mixture. How to read your spark plugs, they are telling you whats. Spark plug heat range is too cold for the operating conditions. The insulator is often tinted the color of charcoal. Today it just decreases the size of the spark which can promote a lean misfire in a pollutioncontrolled engine. If the plugs are a golden brown, they have been burning well at the proper temperature. Step 7 of 8strictly aircooled san diego whatever your plugs look like, theyll benefit greatly from a vigorous clean up with a brass brush. The plugs on the right would probably indicate imminent failure for a 2stroke. If your engine is running perfectly, then this part of the plug would soon become a tan color.
Now we compare the looks of the spark plug with our reference image. As a result, normal combustion deposits do not have an opportunity to fluffoff as they normally do. When reading the plug, dont pay as much attention to the bit at the top of the threads. This area is prone to have some minor carbon build up no. Run your gas tank down to a 14 or drain to there, and then put 5 gal of e85 in and run for about 10 miles to get it into the system. This condition indicates that spark plug temperatures have risen suddenly during a hard, fast acceleration period.
Immediately stop and remove the spark plug be careful, its hot. Dry and wet fouling although there are many different cases, if the insulation resistance between the center electrode and the shell is over 10 ohms, the engine can be started normally. The oil is probably coming from the worn out valve cover gaskets and puddling in the spark plug. Both the fuel mixture and the ignition timing result in coloring of the spark plugs porcelain and ground strap.
Understand how to read the spark plug color car from japan. Dont beat yourself up trying to get a perfectly and evenly colored plug, just make sure that the color that it is is a good color. A known engine builder who works on my type of car recommends running gap at. Car seems to go pretty well, but i feel its a bit underpowered compared to my other mini which is a 1995 spi cooper currently half welded in my garage. Blue is the ideal color of the spark across the plugs gap. A plug chop is one way to verify your main jet jetting. I just read the tuning link that you shared with us and i agree with most everything said except the color of the spark plug. If your spark plug is white in color or appears blistered, that means something is making the plug run too hot.
Now reach into your pocket and get the spark plug wrench you put there and remove the very hot plugs. How to check your spark plug for the correct carburetor setting. A healthy spark plug will have a little bit of electrode erosion but no abnormal deposits while the color would be a light tan, gray, or brownish. This plug eventually fouled and the bike would not start. Airfuel mixture is too rich, the carburetor settings are incorrect. By examining the spark plug insulator color, an experienced personal watercraft engine tuner can determine valuable information. Oct 20, 2014 page 1 of 2 spark plug colour running lean. Checked the valves last night and they were very close to spec, the real issue is the thing failed smog, is running rich, i cant get it registered because of the smog. As for other examples and what to look for, here is a chart which shows pretty well a good range of what spark plugs might look like. Finally, poor engine performance and a loss in fuel economy are traits of a worn spark. Spark plug color evidence of what is happening inside. Dec 11, 20 if you want to test if its spark or fuel just pull the spark plugs, replace them, but put a small squirt of fresh straight gas into the spark plug hole before installing the new plugs.
96 252 335 208 419 239 471 835 1355 1480 1314 842 1479 129 829 388 89 1381 423 904 538 159 473 687 1475 1275 315 1002 480 1117 1423 761