V-Twin Knucklehead Left Engine Case 1941-1947 For Harley-Davidson FL

This Knucklehead Left Engine Case for Harley-Davidson FL (1941–1947) provides a durable, rebuild-ready foundation for vintage engines, featuring a steel bearing insert cast-in and machined to fit the OEM right side case for precise alignment.

• Serial number pad measures approximately 5/16 inch wide by 2-1/4 inches long; a line between the pad and case appears on models from 1936–42.
• Steel bearing insert cast-in for durability.
• Machined to fit OEM right side case with precise alignment; not a bolt-in installation.
• Requires line lapping of the main case races and may require additional machining before installation.
• Designed for use with specific accessory items for optimal fit, including the #10-1758 Knucklehead Right Side Engine Case and #60-0258 Motorshop Case Matching Machine Service.
• Accommodates the short rib case (1936–mid 1941) and the high rib case (1941–1947) for added strength, especially for 74 cubic inch engines.
• Cylinder deck height and motor mount surfaces are approximately 1/16 inch taller than standard cases; features a blank boss for serial number placement.
• Fits Harley Davidson FL models from 1941 to 1947.
• Installation requires experience; areas must be machined separately and careful measurement is required for proper operation.
• Pairs well with additional accessory items and is intended for restoration or customization projects demanding authenticity and compatibility with original and aftermarket parts.

Knucklehead left hand engine case features steel bearing insert cast in and is machined to fit OE right side case. Machined steel insert case in place. Case is not a bolt in installation.

This V-Twin 1941-1947 Knucklehead Left Engine Case is designed for Harley Davidson FL models from 1941 to 1947, providing a durable and reliable foundation for engine rebuilds and restorations. Crafted from high-quality materials, this case features a serial number pad measuring approximately 5/16 inch wide and 2-1/4 inches long, with a distinct line between the pad and the case on models from 1936-42. The case includes a steel bearing insert cast-in, ensuring robust support for engine components. Machined to fit OEM right side cases, it ensures precise alignment and compatibility with original parts, making it suitable for professional engine assembly and customization. The case set requires line lapping of the main case races and may need additional machining before installation, especially around the flywheel fit and mounting surfaces. It is recommended to use with specific accessory items like the #10-1758 Knucklehead Right Side Engine Case and #60-0258 Motorshop Case Matching Machine Service to achieve optimal fit and performance. Notably, the cylinder deck height and motor mount surfaces are approximately 1/16 inch taller than standard cases, and the case features a blank boss for serial number placement. The design accommodates the short rib configuration used from 1936 to mid-1941, with the later high rib design introduced in 1941 through 1947 for added strength, especially for 74 cubic inch engines. Installation requires experience as areas must be machined separately, and it is not a bolt-on component. The case pairs well with additional accessory items and requires careful measurement and fitting for proper operation. Overall, this case offers a high-quality, historically accurate component for restoring or customizing vintage Harley Davidson engines, ensuring durability and compatibility with original and aftermarket parts.

Features:

• Serial number pad: 5/16 inch wide and 2-1/4 inch long, with line between pad and case on 1936-42 models

• Steel bearing insert cast-in for durability

• Machined to fit OEM right side case with precise alignment

• Requires line lapping of main case races and additional machining before installation

• Designed for use with specific accessory items for optimal fit

• Accommodates the short rib case (1936-mid 1941) and high rib case (1941-1947) for added strength

• Compatible with Harley Davidson FL models from 1941 to 1947

Fitment:
Harley Davidson FL 1941
Harley Davidson FL 1942
Harley Davidson FL 1943
Harley Davidson FL 1944
Harley Davidson FL 1945
Harley Davidson FL 1946
Harley Davidson FL 1947