Main Bearings, .040 Case, .020 Crank, Standard Thrust

OVERVIEW

When you are deep into a performance engine rebuild, precision is not just a goalit is a requirement. These EMPI Main Bearings are specifically engineered for air-cooled Volkswagen engines where the engine case has been bored out .040 inches (1.00mm) and the crankshaft journals have been ground down .020 inches (0.50mm) under stock specifications. This particular set features a standard thrust configuration, making it the ideal choice for builders working with a case that has not had the thrust surface machined. At Appletree Auto, we know that the backbone of any reliable Type 1, Type 2, or Type 3 engine is the bearing set. These Silverline steel-backed bearings provide the structural integrity and superior oil retention properties necessary to maintain consistent oil pressure, even under the high-heat conditions typical of the VW flat-four boxer engine design.

Choosing the right bearing size is critical to the longevity of your build. A .040 case cut is often necessary for older magnesium or aluminum cases that have seen significant wear or have "pounded out" over decades of use. By utilizing these oversized case bearings, you can salvage a vintage case and return it to a perfectly concentric state. The .020 crank cut allows you to reuse a forged German crankshaft that may have had surface scoring or slight ovaling, saving you the expense of a new rotating assembly without sacrificing performance. These bearings are manufactured to exacting tolerances, ensuring that your oil clearances are spot-on for a smooth-running, long-lasting motor. Don''t settle for inferior components when your engine''s internal friction surfaces are on the line; trust the brand that has been a staple in the VW community for generations.

FITMENT

• Volkswagen Beetle: 1966-1977 (1300cc, 1500cc, and 1600cc engines)
• Volkswagen Super Beetle: 1971-1979
• Volkswagen Karmann Ghia: 1966-1974
• Volkswagen Bus / Transporter: 1963-1971 (Type 2 with 1500cc or 1600cc upright engines)
• Volkswagen Type 3 (Squareback, Fastback, Notchback): 1966-1973
• Volkswagen Thing (Type 181): 1973-1974
• Custom Applications: Any air-cooled VW Type 1 based engine (1300-1600cc case)

SPECS

• Case Bore Diameter: .040 inches (1.00mm) Oversize
• Crankshaft Journal Diameter: .020 inches (0.50mm) Undersize
• Thrust Surface: Standard
• Material Construction: High-strength Steel-backed Alloy
• Manufacturer: Silverline / EMPI
• Part Number: 111-198-485
• Engine Compatibility: 1300cc, 1500cc, 1600cc, and 1600cc Dual Port
• Oil Holes: Precision pre-drilled for optimal lubrication flow
• Finish: Silverline silver-grade anti-friction coating

PRO TIPS

1. Verification of Machining Dimensions

Before you even open the plastic packaging of your new bearings, you must verify the dimensions of your machine work with a high-quality micrometer. It is a common mistake to assume the machine shop finished the case or crank to the exact specs requested. Measure the main journals of your crankshaft to ensure they are exactly .020 under stock, and check your case bore to confirm the .040 oversize. Installing bearings into a case or onto a crank that does not match the bearing specs will lead to immediate oil pressure failure or catastrophic engine seizure. Measure twice, build onceit''s the golden rule of the air-cooled specialist.

2. Proper Bearing Tang Alignment

When installing these bearings into the case halves, pay close attention to the locating tangs and the dowel pins. The main bearings for a VW air-cooled engine are "pinned" to prevent them from spinning within the case. Ensure that the holes in the bearings line up perfectly with the pins in the case. If a bearing is not seated correctly on the pin, the case halves will not close properly, and tightening the case nuts will crush the bearing and ruin your build. Use a small amount of assembly lube to hold the bearing in place, but never use RTV or silicone on the bearing shells themselves, as this can block vital oil passages.

3. Checking Crankshaft End Play

Since this set features a "Standard Thrust" bearing, it assumes your engine case has not had the thrust surface (the area where the #1 main bearing sits) machined. After you have the case halves torqued to specification, you must check your crankshaft end play using a dial indicator. The thrust bearing is responsible for controlling the forward and backward movement of the crankshaft. If your end play is not within the factory spec (typically .003 to .005 inches), you will need to adjust your flywheel shims accordingly. Never skip this step; improper end play can lead to premature bearing wear and damage to the engine case and crankshaft.