Rear Main Seal, 1.7-2.0 L Type 4 VW Engines

OVERVIEW

When it comes to the heart of your Volkswagen Type 4 engine, the rear main seal is the unsung hero that stands between a clean, high-performing machine and a catastrophic clutch failure. This premium EMPI silicone rear main seal is engineered specifically for the demanding environments of the 1.7L, 1.8L, and 2.0L powerplants found in late-model Buses and Vanagons. Unlike standard rubber seals that can harden and crack under the intense heat cycles of an air-cooled or early water-cooled engine, this silicone variant offers superior flexibility and thermal resistance. As any seasoned VW builder knows, the labor involved in reaching this sealpulling the engine and removing the flywheelis significant. Installing anything less than the highest quality silicone seal is a risk that simply isn''t worth taking. This seal ensures a tight, long-lasting barrier that keeps your engine oil where it belongs and your clutch disc bone-dry for maximum engagement.

Whether you are performing a routine clutch replacement, adding shims to set your crankshaft endplay, or conducting a full performance rebuild, this rear main seal (Part # 029-105-245B) is a mandatory replacement item. Oil seepage from a worn-out seal is the leading cause of clutch chatter and slippage, often ruining a brand-new pressure plate and disc in a matter of miles. This specific seal is designed to handle the higher crankcase pressures often seen in high-mileage Type 4 engines, providing a robust sealing surface against the flywheel hub. Don''t let a few dollars stand between you and a leak-free garage floor. At Appletree Automotive, we recommend this premium silicone version for every Type 4 build to guarantee that once the engine is back in the bay, it stays there without the need for a "do-over" due to annoying oil drips.

FITMENT

• VW Type 2 Bus: 1972-1979 (1.7L, 1.8L, & 2.0L Type 4 Engines)
• VW Vanagon: 1980-1983 (2.0L Air-Cooled Engines)
• VW Vanagon (Water-Cooled): 1983.5-1991 (1.9L & 2.1L WBX Engines)
• VW Vanagon Syncro: 1986-1991 (All 4WD Models)
• VW Type 4 (411/412): 1968-1974 Models
• Porsche 914: 1970-1976 (1.7L, 1.8L, & 2.0L 4-Cylinder Engines)

SPECS

• Material: Premium High-Temp Silicone
• Seal Type: Double-Lip Design for maximum oil retention
• Engine Application: VW Type 4 / Pancake / WBX
• Inner Diameter: Optimized for 1.7L - 2.0L Flywheel Hubs
• Outer Diameter: Precision fit for Type 4 Engine Case Bore
• OEM Cross Reference: 029-105-245B
• Color: Typically Orange or Brown (Silicone Grade)
• Quantity: Sold Individually

PRO TIPS

1. Master the Surface Preparation

Before you even think about tapping that new seal into place, you must inspect the flywheel hub and the engine case bore with a critical eye. Use a lint-free cloth and a high-quality solvent to remove every trace of old oil and debris. Most importantly, check the sealing surface on the flywheel hub for a "groove" worn in by the previous seal. If you can feel a ridge with your fingernail, the new seal may not seat properly, leading to immediate leaks. In such cases, you might need to slightly offset the seating depth of the new seal or replace the flywheel. Always apply a very thin film of clean engine oil or assembly lube to the inner lip of the seal to prevent "dry start" friction, which can burn the seal lip before the oil pressure even builds up.

2. Use the Right Driver for Level Installation

The most common cause of rear main seal failure is "cocking" the seal during installation. If the seal goes in slightly crooked, the tension on the crankshaft will be uneven, and it will leak almost immediately. We recommend using a dedicated seal driver tool or a large-diameter PVC pipe coupling that matches the outer diameter of the seal perfectly. Gently tap around the perimeter in a "star" pattern until the seal is flush with the engine case. Never use a screwdriver or a small punch to drive it in, as you risk piercing the silicone or distorting the internal metal spring. Ensure the internal tension spring is still properly seated inside the lip after installation, as it can occasionally pop out if the seal is handled roughly.

3. Don''t Forget the Flywheel O-Ring and Endplay

While you have the flywheel off to replace the rear main seal, you are only halfway there. On Type 4 engines, there is an O-ring located inside the flywheel hub that seals the crankshaft to the flywheel itself. If you replace the main seal but ignore this O-ring, oil will still find its way onto your clutch via the crankshaft splines. Always replace both at the same time. Additionally, this is the perfect moment to verify your crankshaft endplay using a dial indicator. Removing the flywheel can sometimes shift your shims; ensuring that your endplay is set to factory specifications (typically .003 to .005 inches) ensures that the crankshaft doesn''t "walk" too much, which would otherwise put unnecessary lateral stress on your brand-new silicone seal.