Orange spark workhorse not cranking

[rodger_10]

I have an ignitor for a MCI # is 2857540101. My workhorse has a 2003 350 Robins engine. I am getting a very small orange spark at the spark plug wire. Could my ignitor be bad? Could it be the ignition coil, I have the MCI one on my cart. I don't know how to test either one of them. I have checked the wires and they look good. Thanks for any info.

[golfcartg]

It sounds like you could be dealing with a grounding issue which is a common culprit for the problem you're experiencing.

Usually the OEM ignition system only breaks down under rare circumstances such as reversing the polarity on the battery or sparking during a jumpstart. I highly recommend starting by checking and cleaning all the ground connections. If you have an aftermarket coil or ignitor installed, consider replacing it with an OEM part from an authorized dealer. Aftermarket ignition components often lack the quality and reliability needed in this system leading to frequent malfunctions.

Make sure that the ground wires are firmly attached and free of corrosion. To troubleshoot, with all the grounds cleaned, run a fresh ground wire from the battery negative terminal to the ignition coil mounting plate. This will help rule out any grounding issues before considering more complex solutions.

With the grounds clean and in tact and if the problem still persists, i'm attaching a guide for you to check your ignition system thoroughly. Testing these components typically involves using a multimeter to check for proper resistance values and continuity verifying they are functioning correctly.

Assuming you've already covered the basics like inspecting the spark plugs for wear or damage and replacing them if necessary. Like you said, checking the spark plug wires for cracks or signs of wear that could lead to weak or erratic sparks. Additionally, double check that the battery is in good condition and fully charged as a weak battery can affect the performance of the ignition system. Feel free to share your results and any further questions you might have, we're interested in hearing how it goes.

[rodger_10]

My ignition coil seems to be ohming out correctly. I am getting 10 volts to the coil. I will charge up the battery and try it again. The spark plugs are new. When the engine did run it would foul the plugs after going around the yard picking up trash and such or if you drove it continuous. Checked wiring and seem good.

[golfcartg]

Are you currently experiencing a no-run situation? Does the engine run intermittently? If it's not running, do you have compression readings of 150 psi or higher and does it start momentarily when you put a few drops of gasoline into the combustion chamber through the spark plug holes? I want to address the potential no-run situation before we move on to the fine tuning information below. I have extensive experience in restoring a poorly running Robin to optimal performance. I've successfully brought many back to life and fine tuned them for reliable operation.

Most importantly, aftermarket parts, while often cheaper, are not made to the exact delicate standards required by the Robin engine. This is particularly true for the carburetor. Aftermarket carburetors, though marketed as compatible, frequently fall short. They have minor variances in jet sizes, float settings, and overall build quality leading to inconsistent fuel delivery and poor engine performance. If your EZGO's carburetor is aftermarket, it is highly recommended to replace it with a carburetor purchased directly from EZGO.

Knock off spark plugs can cause a myriad of problems including misfires and fouling which you were experiencing. Replace them with NGK BP5ES plugs sourced directly from NGK to avoid counterfeit products. Additionally, these plugs should be gapped at .030 inches.

Low quality fuel can lead to a variety of problems including general poor performance. If the fuel in your tank is of questionable quality, it’s worth draining the tank and refilling it with a higher octane fuel. According to the manual, fuel closer to 100 octane is recommended. The higher octane fuel helps with cleaner combustion.

An intake that is not completely sealed can introduce unmetered air into the engine disrupting the delicate air-fuel mixture and leading to poor performance and fouling of the spark plugs. Check the intake gaskets to confirm they are in place and not damaged. If any gasket appears to be worn or damaged, it should be replaced immediately so that the engine receives the correct air-fuel mixture. The pilot screw on top of the carburetor plays a role in fine tuning the air-fuel mixture at idle. It should be adjusted to 1 1/4 turns out from fully closed. This setting provides a good baseline for the air-fuel mixture and can help resolve idle issues and improve overall engine performance. If the pilot screw is not correctly adjusted, the engine might run too rich or too lean.

If you have addressed all these factors and still experience problems, the issue might lie with the valve lash. Incorrect valve lash can lead to poor engine performance, including loss of power, increased wear, and potential engine damage. Adjusting the valve lash requires precise tuning skills and can be difficult to achieve with a feeler gauge so I always recommend changing this setting only as a last resort to avoid making this potentially worse. You can adjust the valve lash by lightly butting each valve against the cam lobe, then backing off 1/4 turn and tightening in place. This method can get you within 99% accuracy of the factory specifications since the exact specifications are difficult to achieve using a feeler gage. Given the symptoms you're describing like fouled spark plugs and intermittent operation, it's possible that incorrect valve lash is contributing to these problems by affecting the combustion process.

[rodger_10]

Are you currently experiencing a no-run situation? Does the engine run intermittently? If it's not running, do you have compression readings of 150 psi or higher and does it start momentarily when you put a few drops of gasoline into the combustion chamber through the spark plug holes? I want to address the potential no-run situation before we move on to the fine tuning information below. I have extensive experience in restoring a poorly running Robin to optimal performance. I've successfully brought many back to life and fine tuned them for reliable operation.

Most importantly, aftermarket parts, while often cheaper, are not made to the exact delicate standards required by the Robin engine. This is particularly true for the carburetor. Aftermarket carburetors, though marketed as compatible, frequently fall short. They have minor variances in jet sizes, float settings, and overall build quality leading to inconsistent fuel delivery and poor engine performance. If your EZGO's carburetor is aftermarket, it is highly recommended to replace it with a carburetor purchased directly from EZGO.

Knock off spark plugs can cause a myriad of problems including misfires and fouling which you were experiencing. Replace them with NGK BP5ES plugs sourced directly from NGK to avoid counterfeit products. Additionally, these plugs should be gapped at .030 inches.

Low quality fuel can lead to a variety of problems including general poor performance. If the fuel in your tank is of questionable quality, it’s worth draining the tank and refilling it with a higher octane fuel. According to the manual, fuel closer to 100 octane is recommended. The higher octane fuel helps with cleaner combustion.

An intake that is not completely sealed can introduce unmetered air into the engine disrupting the delicate air-fuel mixture and leading to poor performance and fouling of the spark plugs. Check the intake gaskets to confirm they are in place and not damaged. If any gasket appears to be worn or damaged, it should be replaced immediately so that the engine receives the correct air-fuel mixture. The pilot screw on top of the carburetor plays a role in fine tuning the air-fuel mixture at idle. It should be adjusted to 1 1/4 turns out from fully closed. This setting provides a good baseline for the air-fuel mixture and can help resolve idle issues and improve overall engine performance. If the pilot screw is not correctly adjusted, the engine might run too rich or too lean.

If you have addressed all these factors and still experience problems, the issue might lie with the valve lash. Incorrect valve lash can lead to poor engine performance, including loss of power, increased wear, and potential engine damage. Adjusting the valve lash requires precise tuning skills and can be difficult to achieve with a feeler gauge so I always recommend changing this setting only as a last resort to avoid making this potentially worse. You can adjust the valve lash by lightly butting each valve against the cam lobe, then backing off 1/4 turn and tightening in place. This method can get you within 99% accuracy of the factory specifications since the exact specifications are difficult to achieve using a feeler gage. Given the symptoms you're describing like fouled spark plugs and intermittent operation, it's possible that incorrect valve lash is contributing to these problems by affecting the combustion process.

As of now the engine will not start. I get 11.5 to 12 volt at the ignition coil but a weak spark coming off the cable going to the plug. I have checked the resistance at the ignition coil and it seems to be correct. I have had NGK BP5ES and NGK BP4ES in it. I have 150 compression on both cylinders. I have adjusted the valve lash to .028 and .030. I think it is a weak spark going to the plugs. I have seen a lot of videos on you-tube about motor not starting. I am at a loss as to what is causing the problem. I have a new Red Hawk carburetor on it. Checked the muffler and it is not plugged.

[golfcartg]

1. Timing issues, timing belt could be off a tooth
2. Valves are not adjusted properly leading to a no-run situation (see post #4 paragraph 6)
3. With grounding issues ruled out, any aftermarket parts within the ignition system could be a source of trouble or weak spark
4. If the ignition and pulsar coil check out fine, there's no definitive method to test the ignitor other than swapping it with a known functional one. (IE brand new OEM from EZGO)
5. Thumbs up for selecting the Red Hawk carburetor over an Amazon special, though less likely to result in a no-run condition, it's not an OEM part and is not tuned or tested to exact OEM spec leading to issues once the engine is running

Does the engine make any attempt to fire when a few drops of gas are funneled into the cylinders? This could potentially rule out number 1.

I'm attaching the crank (no start) troubleshooting guide which covers the basics, any backstory you can provide leading up to the no-run situation would also be helpful.

Keep us in the loop, were eager to hear about your progress

cc: Michael Eddie

[Michael Eddie]

I think you've done a fantastic job providing troubleshooting guidance so far. I'd like to add some information that hasn't been covered yet, just to be thorough. There's a gap on the pulsar coil that should be checked, and a length of wire connecting the pulsar coil to the harness that could be inspected, although that's less likely considering the pulsar seems to be testing fine (see attached pulsar coil PDF guide).

Other than that, I want to touch base again on how important clean grounds are in this system. Be sure to sand down all grounds to the shiny metal, especially where the ignition coil mounts to the bracket (see attached image). Then run your new ground from the B- to the ignition coil bracket. Finally, check to make sure all of your intake gaskets and spacers are brand new and in place (see attached pic #2).