Fueling the Future: Igniting Alternative Fuels in Heavy-Duty Vehicle and Industrial Engines with E3 Spark Plugs

Fleet managers of heavy-duty trucks, buses, and industrial engines are increasingly embracing alternative fuels to comply with surging environmental regulations. Reaching challenging corporate sustainability goals puts additional pressure on maintenance and purchasing managers. To meet these challenges, the use of natural gas, liquefied natural gas (LNG), compressed natural gas (CNG), and renewable bio-gas (RNG) is growing. We’re looking at how E3 Spark Plugs meets the demand for improved performance and sustainability with alternative fuels.

Natural gas powers nearly 200,000 vehicles in the U.S. and over 23 million vehicles worldwide. Transit and school buses and concrete mixers are examples of heavy-duty vehicles converting to zero-emission (ZE) technology at a high rate, with refuse and long-haul trucks leading adoption, according to a published report by the State of Sustainable Fleets. 

Hearing from an Ignition Technology Expert: Cutting-Edge Design and Material Advances in Spark Plugs

In the KIRKS’ ongoing ToolBOX webinar series, where we bring product experts to you, Bob Kirkman met with Joe Wolf, E3 Spark Plugs’ Sales and Marketing leader. Joe brings 30 years of expertise in the original equipment (OE) and aftermarket parts markets. He has focused on ignition technology for heavy-duty trucks, transit buses, and industrial engines since 2016. 

Joe’s presentation covered the evolution of E3 Spark Plugs for heavy-duty engine solutions. He discussed fuel combustion challenges with differing alternative fuel quality levels in extreme environments and offered tips for extending spark plug lifespan.

Challenges to Optimum Combustion in Heavy-Duty Engines Using Alternative Fuels 

An engine powered by propane, natural gas, LNG, CNG, or RNG requires spark plugs to reliably ignite the air-fuel mixture in the combustion chamber. 

When sourcing replacement parts, maintenance professionals must decide on the best materials that provide extended life, deliver performance, and meet budget requirements. Using inferior spark plugs can have annoying and costly consequences:

  • Engine starting difficulty
  • Inefficient and inconsistent combustion
  • Frequent replacement
  • Wider spark plug gap
  • Decreased fuel mileage
  • Poor acceleration
  • Damaged or melted electrodes
  • Misfires

Wolf highlighted the importance of preventing misfires: “Misfires can be detrimental, as everybody knows. It actually can take an SCR (selective catalytic reduction) unit out, or they’re limping back to home base trying to repair the misfire.”

Making the Right Choice Between Platinum and Iridium for Heavy-Duty Engine Performance

While spark plug technology has advanced, Joe Wolf noted that many competitors’ spark plugs still employ platinum. The low melting points of these metals make them unsuitable for use with alternative fuels. Further, natural gas and hydrogen rapidly oxidize platinum.

E3 engineers have found that iridium performed better in igniting alternative fuels within the combustion chamber. So, what is iridium?  

While iridium led to improved results, E3 discovered that combining iridium with another material, rhodium, improved performance even more. 

How E3 Spark Plugs’ Research Led to Making Significant Advances in Ignition Technology 

Wolf discussed how E3’s years of research and independent testing led to significant improvements in spark plug longevity and performance by combining two tough metals.

“We utilize iridium with rhodium, so those alloys will actually achieve higher temperatures and lower erosion opportunities for longer life.” – Joe Wolf, E3 Spark Plugs

Working with leading automotive universities, E3 found:

  • Combining the two metals helped prevent oxidation and maintain the proper gap size. 
  • Too small of a gap can result in poor performance, while a wide gap impacts efficiency, economy, and power availability.
  • The correct gap size extended the spark plug’s life and lowered stress from power demands on the ignition coil. 
  • While spark plugs relying on platinum may cost less, the electrode bubbles up as it melts under extreme heat. 

“If you have melting, it’ll bridge the gap, and you’ll introduce misfires,” said Wolf. “Also, our center electrode is much larger than the OE by 30%, translating into longer life.” 

Cummins Ground Electrode Melting

Research lab photograph showing platinum bubbling on spark plug electrodes from high, uneven temperatures in combustion chambers

Better Metals Improve Engine and Ignition Performance 

Benefits of choosing E3 Spark Plugs replacements include: 

  • Overcoming Combustion Issues – E3’s unique double iridium-rhodium spark plugs efficiently burn fuels in engines using natural gas, CNG, RNG, and LNG for optimal combustion, improving performance and reducing emissions.
  • Enhanced Ignition Technology – the 30% larger electrode design and higher spark voltage ensure consistent and powerful ignition, maximizing fuel burn and improving engine performance.
  • Extended Service Life – E3 spark plugs withstand the punishing conditions of heavy-duty commercial use.
  • Reduced Maintenance Costs –Durable spark plugs reduce replacement frequency at a competitive cost and save valuable technician time. 
  • Compatibility and Easy Installation – Drop-in E3 Spark Plugs replace OEM spark plugs and ignition coils for heavy-duty trucks, buses, and industrial engines. 
E3 Spark Plug kit and coil on plug

E3 Heavy-duty Spark Plug and Coil-on-Plug Kits

E3 Spark Plug and Coil-on-Plug (COP) Kits Exceed OEM Requirements for Unmatched Performance and Long Life

Modern heavy-duty fleets and industrial engines using alternative fuels have a distributor-less “coil-on-plug (COP)” system. Each cylinder has its ignition coil. This system allows individual optimized control over ignition timing for increased horsepower and reduced emissions.

During the webinar, Wolf described the E3 spark plug kits and complete COP ignition. The COP contains an insulating tube, and a protective boot to resist extreme temperatures. Spark plug kits also include protective boots. 

E3 designed its COP solution to exceed OEM specifications for durability and reliability. The primary system voltage is 12-14 volts, with a secondary output range of 15KV to 20KV. 

Here are a few of E3’s Spark Plug and COP unique features:


  • Coil head & extension ignition capacity, extreme heat, durability, and reliability exceed OEM.
  • Methyl vinyl silicone rubber boot rating 500°F / 260°C and strong dielectric properties exceed OEM.
  • DuPont® Krytox 205 dielectric grease pre-applied to boots and extension seals meets OEM requirements.
  • Translucent FEP tube, strong dielectric properties exceed OEM.  Stainless steel springs, increased spark plug contact, and durability exceed OEM.
  • Coil extension is also available separately as a replacement item.

E3 Spark Plug Kits

  • Double Iridium-Rhodium technology acquired from natural gas industrial engines.
  • Iridium-Rhodium alloy center electrode surface exceeds OEM by 30%.
  • Higher iridium-rhodium alloy melting points reduce incidents of alloy melting and bridge the gap misfires.
  • Methyl vinyl silicone rubber boots rating 500°F / 260°C and stronger dielectric properties exceed OEM.
  • DuPont® Krytox 205 dielectric grease is pre-applied to boots and meets OEM requirements.

Providing Lasting Protection and Insulation for Electrical Connections in Transit and Heavy-Duty Vehicles

E3 manufactures its COP and spark plug kit boots using methyl vinyl silicone rubber, an advanced, durable material. Wolf explained, “This boot is stronger in its dielectric properties and sealing capability.” 

  • Methyl vinyl silicone withstands up to 500 degrees Fahrenheit without melting and voltage leakage.
  • E3 robotically pre-applies the precise DuPont Krytox 205 dielectric grease required on all boots and extension seals.  
  • Beyond dielectric protection, DuPont Krytox 205 provides plug installation and removal convenience. 

Based on extensive development work, E3 natural gas engine products offer reliable and efficient solutions for heavy-duty vehicle engines. Their ignition technology solutions overcome combustion issues caused by using different or lower-quality fuels in demanding operating conditions. 

 Competitive Pricing That Doesn’t Sacrifice Performance: KIRKS Provides the Parts to Keep Heavy-Duty Vehicles on the Road

Surprisingly, E3 heavy-duty spark plugs, engineered with superior materials that outperform competitors, can be sourced at competitive replacement costs.

With E3 Spark Plugs, maintenance professionals can expect extended vehicle service life, reduced maintenance costs, and the savings of valuable technician time. Check out KIRKS’ line of E3 products on our website.

As your trusted partner for heavy-duty replacement parts, we can help you quickly navigate the complex parts maze. Talk with a KIRKS Product Specialist today!