Main Bearings, .020 Case, .010 Crank, .040 Thrust

Overview

When it comes to rebuilding a vintage air-cooled Volkswagen engine, precision is the difference between a motor that lasts for decades and one that fails within the first thousand miles. These EMPI Silverline main bearings are engineered for those specific "saveable" engines where the case and crankshaft have seen better days but still have plenty of life left in them. If your engine case has been line-bored .020 inches over to correct for warping or "pounding out" of the bearing saddles, and your crankshaft journals have been turned .010 inches under to remove scoring or taper, this is the exact set you need. These aren''t just off-the-shelf replacements; they are specialized components designed to restore factory-spec tolerances to a heavily machined long block, ensuring that your oil pressure remains rock-solid even in the heat of a desert summer or the stress of a highway cruise.

The quality of Silverline bearings is legendary in the VW community, featuring a robust steel-backed construction that provides the structural integrity required to withstand the high-revving demands of a performance 1600cc build or the low-end torque of a heavy camper bus. This particular set also addresses the thrust surface, featuring a .040 inch oversized thrust cut. This is vital for cases where the thrust face has been machined to remove damage from excessive end-play. By using these bearings, you are effectively "resetting" the internal geometry of your engine. At Appletree Automotive, we understand that every thousandth of an inch matters. That is why we stock these high-quality, steel-backed bearingsto give you the confidence that your Type 1, Type 2, or Type 3 engine is spinning on the best possible foundation.

Fitment

This bearing set is designed for air-cooled Volkswagen Type 1 based engines (1300cc, 1500cc, and 1600cc) that have undergone specific machining. This includes:

• Volkswagen Beetle: 1966-1977 (Standard and Super Beetle)
• Volkswagen Karmann Ghia: 1966-1974
• Volkswagen Bus / Type 2: 1963-1971 (With 1500cc or 1600cc upright engines)
• Volkswagen Type 3 (Squareback, Fastback, Notchback): 1966-1973
• Volkswagen Thing: 1973-1974
• Custom Applications: Dune Buggies, Sand Rails, and Trikes utilizing a VW Type 1 engine case.

Technical Specifications

• Brand: EMPI / Silverline
• Construction: High-strength steel-backed alloy for maximum durability.
• Case Bore Diameter: .020 inches (0.50mm) Oversize (Requires a case line-bored to this spec).
• Crankshaft Journal Diameter: .010 inches (0.25mm) Undersize (Requires a crank turned to this spec).
• Thrust Surface: .040 inches (1.00mm) Oversize (Requires the case thrust face to be machined).
• Engine Compatibility: 1300-1600cc Type 1, 2, and 3 air-cooled engines.
• Part Number: 111-198-473OS
• Weight: 0.75 lbs

Pro Tips from the Master Bench

1. Always Verify the Machinist''s Work

Even if you trust your machine shop implicitly, never install bearings without measuring first. Use a high-quality micrometer to check your crankshaft journals and a dial bore gauge to check the line-bore in the case. This bearing set is a "triple-cut" variety (.020/.010/.040), and even a small error in communication with the machinist can lead to a catastrophic failure. Before you apply assembly lube, do a "dry fit" of the bearings in the case halves and ensure they sit flush and the dowel pins align perfectly with the holes in the bearings. If the bearing doesn''t snap into place with a slight click, or if it rocks, something is wrong with the bore.

2. The Importance of the Thrust Bearing Surface

The .040 inch thrust cut on this bearing set is designed to fix "end-play" issues. When installing the crankshaft, pay extra attention to the #1 bearing (the one closest to the flywheel). This is the bearing that handles the lateral load when you depress the clutch. Ensure the case surface where this bearing seats is perfectly smooth and free of burrs. After the case halves are torqued to spec, you must measure your end-play using a dial indicator. If your end-play isn''t between .003 and .005 inches (standard spec), you will need to adjust your flywheel shims accordingly. A .040 thrust cut gives you a lot of material to work with, but it must be shimmed correctly to prevent premature wear.

3. Cleanliness and Oil Gallery Prep

Before installing these Silverline bearings, ensure the oil galleries in the case and the crankshaft are surgically clean. When a case is line-bored or a crank is turned, fine metal shavings can hide in the oil passages. Use a set of engine brushes and high-pressure solvent to scrub every internal passage. When you are ready for final assembly, use a dedicated engine assembly lubenot just motor oil. The assembly lube provides a sticky, protective film that stays on the bearing surface during the initial "dry start" before the oil pump has fully pressurized the system. This is especially critical on the .010 undersize crank journals where the oil clearance is tight and precision is paramount.