Installing Nickel Alloy Valve Seats

Published on December 2, 2021
Duration: 9:11

Mel Bernstein, 'The Dragon Man,' provides an advanced guide on rebuilding 1976 Shovelhead Harley-Davidson flywheels. The process involves meticulous cleaning, precise torquing of critical components like the pinion shaft and crank pin nuts, using specialized jigs and a press for alignment, and truing the assembly with dial indicators. A key emphasis is placed on using the correct pinion shaft bushings to ensure proper oiling, preventing catastrophic engine failure.

Quick Summary

Rebuilding Harley-Davidson Shovelhead flywheels involves meticulous cleaning, precise torquing to specifications like 125 ft-lbs for the pinion shaft nut, and using specialized tools. Crucially, selecting the correct pinion shaft bushing is vital to prevent oil starvation and engine seizure.

Chapters

  1. 00:00Introduction and Flywheel Cleaning
  2. 00:181976 Shovelhead Flywheel Prep
  3. 00:32Pinion Shaft Torque Specs
  4. 00:42Flywheel Jigs and Nut Tightening
  5. 01:11Crank Pin Installation and Keyway
  6. 01:26Crank Pin Types: Jim's vs. Harley
  7. 01:44Crank Pin Nut Torque
  8. 02:24Torrington Roller Bearings
  9. 02:39Connecting Rod Installation
  10. 03:00Sprocket Shaft Side Installation
  11. 03:20Shaved Flywheels for Performance
  12. 03:49Pressing the Flywheel Assembly
  13. 04:04Ensuring 90-Degree Crank Pin Alignment
  14. 04:28Final Crank Pin Torque
  15. 05:05Truing the Flywheels
  16. 05:25Using Dial Indicators
  17. 05:41Adjusting Flywheel Runout
  18. 06:21Overnight Settling for Accuracy
  19. 06:34Critical: Pinion Shaft Bushing Importance
  20. 07:11Cam Cover Pinion Shaft Bushing Differences
  21. 07:54Side Oiler vs. Non-Oiler Bushings
  22. 08:04Consequences of Mismatched Bushings
  23. 08:36Rebuilt Rods and Weekly Workload
  24. 08:45Causes of Flywheel Rust
  25. 08:57Conclusion and Contact Information

Frequently Asked Questions

What is the correct torque specification for the pinion shaft nut on a 1976 Harley-Davidson Shovelhead flywheel assembly?

The pinion shaft nut on a 1976 Harley-Davidson Shovelhead flywheel assembly should be torqued to 125 foot-pounds. This ensures proper seating and prevents premature wear.

Why is using a three-hole crank pin recommended over a factory Harley-Davidson single-hole crank pin?

A three-hole crank pin, like those from Jim's Machining, offers improved oil delivery to the connecting rods compared to the factory single-hole version. This enhanced lubrication is crucial for engine longevity.

What is the most common cause of flywheel rebuild failures leading to engine seizure?

The most common cause of flywheel rebuild failures is using the incorrect pinion shaft bushing. Mismatched early (side oiler) and late cam cover bushings can starve the bearings and rods of oil, leading to seizure.

How are Harley-Davidson flywheels trued after assembly?

After assembly and pressing, flywheels are trued on a stand using dial indicators to measure runout. Adjustments are made by carefully tapping the flywheel assembly with a wedge and hammer on the opposite side of the deviation.

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