Service & Inspection for Willys M38

Why Sealant and Spark Plugs Need Regular Replacement on the Willys M38.

The Willys M38 with its rugged Go Devil four-cylinder engine calls for special attention to two often-underestimated areas during maintenance: sealing surfaces and the ignition system. Aging paper gaskets and hardened sealant on the valve cover, oil pan, or transfer case housing lose their elasticity over the years and become porous, leading to oil or gear oil leaks. A heat-resistant RTV silicone sealant reliably closes these weak spots and flexibly conforms to uneven surfaces. At the same time, spark plugs wear out from deposits, electrode erosion, and incorrect gaps, causing misfires, higher fuel consumption, and poor starting behavior – especially noticeable on historic carbureted engines like the L-134. Anyone wanting to keep their M38 road-ready should keep both components in mind during every major service.

• Sealant: The RTV silicone sealant reliably seals the valve cover, oil pan, and housing surfaces, even under heat.
• Ignition System: The matching spark plug ensures reliable ignition and smooth engine running.

American Brand Quality for Sealing and Ignition.

The universal RTV silicone sealant comes from Crown Automotive – American engineering for dependable sealing across all Jeep and Willys model lines. The spark plug is supplied by Champion, one of the best-known American names in ignition technology for decades.

Your Partner for Service and Maintenance on the Willys M38.

Whether it's sealant for your next engine overhaul or spark plugs for the annual service, we're happy to advise on torque specs, electrode gap, and the correct curing time for the sealant before it's put under load. Your order ships from our warehouse as fast as possible.