Oil Cooler Seal Set 8/10mm, For Doghouse Style Oil Cooler

OVERVIEW

In the world of air-cooled Volkswagen performance, thermal management is the difference between a long-lasting engine and a catastrophic roadside failure. These EMPI Oil Cooler Conversion Seals are an essential component for builders who are mixing and matching engine generations or upgrading to the superior "Doghouse" cooling system. During the evolution of the Type 1 engine, Volkswagen increased the oil passage size from 8mm to 10mm to accommodate higher flow and better cooling efficiency. If you are mounting a late-model aluminum Doghouse oil cooler onto an early-model engine case, or trying to adapt an early cooler to a late-model dual-relief case, you cannot simply use standard seals. These "Step Style" seals provide the perfect mechanical bridge, featuring a precision-molded 8mm diameter on one side and a 10mm diameter on the other, ensuring a leak-proof transition that maintains critical oil pressure throughout your lubrication system.

Crafted from high-grade, oil-resistant rubber compounds, these seals are designed to withstand the extreme temperature fluctuations inherent in the VW engine compartment. A leaking oil cooler is more than just a nuisance; it can spray oil onto your cooling fins, attracting dirt and debris that eventually lead to overheating and warped heads. By utilizing these EMPI conversion seals, you are guaranteeing a factory-tight fit even when your components didn''t originally come from the same decade. Whether you are finishing a 1600cc dual-port upgrade on a classic Beetle or plumbing a custom oil bypass adapter for an external filtration system, these seals offer the reliability and structural integrity required for high-performance street or off-road use. Don''t risk your investment with "universal" solutions that fail under pressure; use the specific step-down seals engineered for the air-cooled Volkswagen''s unique oiling architecture.

FITMENT

• Volkswagen Beetle: 1961-1977 (When performing 8mm to 10mm oiling conversions)
• Volkswagen Super Beetle: 1971-1979
• Volkswagen Bus / Type 2: 1961-1971 (1600cc upright engines)
• Volkswagen Karmann Ghia: 1961-1974
• Volkswagen Thing / Type 181: 1973-1974
• Custom Applications: Fits all Type 1, 2, and 3 based engines using Doghouse style oil coolers or bypass adapters requiring an 8mm to 10mm step.

SPECS

• Product Brand: EMPI
• Part Number: 00-9255-0
• OEM Reference Number: 111-117-151B
• Seal Type: Step-Style Conversion (Transition Seal)
• Small Side Diameter: 8mm
• Large Side Diameter: 10mm
• Quantity: Sold as a set of 2 seals
• Material: High-temperature, oil-resistant nitrile-based elastomer
• Application: Doghouse Oil Coolers and Bypass Adapters
• Color: Black

PRO TIPS

1. Verify Your Case and Cooler Dimensions First

Before beginning your assembly, always use a digital caliper to measure the oil galley holes in both your engine case and your oil cooler base. Many "universal" replacement cases or aftermarket oil coolers may have been modified by previous owners. These seals are specifically designed for the transition between the early 8mm galleys and the later 10mm galleys. If both your case and cooler are 10mm, you need standard 10mm seals (white or red usually), and if both are 8mm, you need standard 8mm seals. Using a step seal where it isn''t required will cause a massive oil leak and potential loss of oil pressure within seconds of startup.

2. Proper Orientation is Mandatory

It sounds simple, but the orientation of these seals is the most common point of failure during engine assembly. The smaller 8mm "step" must be seated firmly into the 8mm orifice (typically the engine case on older models), while the larger 10mm side must seat into the cooler or adapter. Ensure that the seal is sitting perfectly flush and hasn''t "cocked" to one side before you begin tightening the oil cooler mounting nuts. If the seal is pinched during the torquing process, it will split, and you won''t know it until your engine is covered in oil during the first test drive. A tiny dab of clean engine oil can help the seal slide into position, but avoid using grease which can cause the rubber to swell prematurely.

3. Never Use RTV Silicone on Oil Cooler Seals

One of the biggest mistakes a novice builder can make is applying RTV silicone or "Gasket Maker" to these oil cooler seals. These seals are designed to work via compression and the natural sealing properties of the rubber against the machined metal surfaces. Applying silicone can actually cause the seal to "spit out" or slide out of its seat as you tighten the cooler down. Furthermore, any excess silicone that squeezes into the oil passage can break off and clog your oil cooler or, worse, an internal oil galley, leading to bearing failure. Keep the surfaces clean, dry, and free of old gasket material, and let the EMPI seals do the mechanical work they were designed for.