Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Automotive Starter Solenoid Remanufacturing Procedures – SAE J2242
This article provides an overview of the remanufacturing procedures for automotive starter solenoids as outlined in SAE J2242 (2008). Although the standard is now designated as noncurrent due to a loss of committee expertise, its recommendations serve as a critical reference for achieving consistent quality, reliability, and safety in solenoid remanufacturing.
Note: SAE J2242 was issued in 1993 and last updated in 2008. It is noncurrent because the committee no longer has members with expertise to maintain the document. Nevertheless, the practices described here remain relevant and provide a solid foundation for remanufacturers.
1. Core Remanufacturing Steps
The following table outlines the primary stages and key requirements for remanufacturing a starter solenoid per SAE J2242.
| Step | Key Requirements |
|---|---|
| Disassembly & Cleaning | Disassemble cap, remove contactor and coil; clean all components without damaging electrical parts. |
| Coil Inspection | Test for open, short, and ground; verify hold-in coil ground. Measure resistance within 10% of original OEM value (accounting for temperature). |
| Contactor Assembly | Check for wear or burning; turn over, repair, resurface, or replace as needed. Inspect rod for bends and insulators for cracks. |
| Cap Assembly | Use new or properly cleaned caps; replace “S” and “R” terminals (or reclaim if necessary). Tighten fasteners to torsional yield strength. |
| Assembly | Install coil and plunger stop, contactor disc, correct gasket, and cap. Ensure proper termination of “S” and motor terminals. |
| Testing | Verify pull-in/hold-in coil, contactor, and “R” terminal operation. Voltage drop across battery and motor terminals must not exceed 0.2 V during starter performance test. |
| Packaging & Marking | Include installation/troubleshooting instructions and all required hardware. Mark unit per FTC regulations (16 CFR 20). |
⚠️ Important: Always evaluate the original design and core condition before processing. Not every core is suitable for remanufacturing. Using inferior or untested replacement parts can compromise quality and safety.
2. Engineering Design and Quality Insights
🔍 A key aspect of SAE J2242 is the emphasis on matching or exceeding original equipment performance. Several design insights are critical for durable operation:
- Coil Resistance Tolerance: The coil resistance must be within 10% of the original value, with allowance for temperature variations. This ensures proper pull-in and hold-in forces.
- Contactor Resurfacing: Worn or burned contactors can be turned over, repaired, resurfaced, or replaced. The goal is to restore the contact surface to a condition equivalent to new.
- Fastener Torque Requirement: Fasteners must be tightened to the torsional yield strength for the grade of thread, not to a specific torque value. This ensures proper clamping force without over-stressing the fastener.
- Voltage Drop Test: A voltage drop of no more than 0.2 V across the battery and motor terminals confirms that the contactor and terminals are performing acceptably under load.
- Replacement Parts Quality: All replacement parts must be carefully evaluated. The “S” and “R” terminals should be replaced if possible; if reclaimed, they must function as new.
- FTC Marking: The remanufactured unit must be clearly marked to comply with U.S. Federal Trade Commission regulations for rebuilt or remanufactured products.
Design insights from the standard also note that while these procedures are universal, unique product features may require special processes or exception tests. Always refer to the original manufacturer’s recommendations when available.
3. Frequently Asked Questions
Q: Why is coil resistance tolerance so important in remanufacturing?
A: The pull-in and hold-in coils work together to engage and hold the starter pinion. If the resistance deviates more than 10% from the original specification, the solenoid may not generate enough magnetic force, leading to unreliable engagement or early failure.
Q: What is the correct way to test the “R” terminal?
A: The “R” terminal (typically used for ignition bypass) should be tested as part of the solenoid functional test. The standard requires verifying proper operation of the “R” terminal in conjunction with the pull-in and hold-in coils. Specific test setups may vary, but continuity and voltage output must match the original design intent.
Q: Can I reuse a contactor disc if it has minor burn marks?
A: Minor burns may be acceptable if the disc can be resurfaced to restore a smooth, even contact surface. However, if the burn is deep or the material is significantly eroded, replacement is required. Always check for flatness and clean the contact area thoroughly.
Q: How do I ensure proper torque when tightening fasteners to torsional yield strength?
A: Torsional yield strength is determined by the fastener grade and thread size. Instead of applying a specific torque value, use a torque-tension tester or reference standard tables for yield point tightening. The goal is to achieve the maximum clamping force without permanent deformation of the fastener.
By following the guidelines in SAE J2242, remanufacturers can produce starter solenoids that deliver reliable performance and meet industry expectations for quality and safety.
