ELRING 804.250 Nuts And Bolts

ELRING 804.250 Nuts And Bolts

The ELRING 804.250 Nuts and Bolts is a precision‑engineered component set designed specifically for the cylinder head of high‑performance engines. This kit delivers the exact torque specifications, material integrity, and geometric tolerances required to maintain optimal compression, seal integrity, and overall engine reliability.

Key Features

• Material Composition: High‑strength alloy steel with a proprietary heat treatment process that ensures superior fatigue resistance under extreme thermal cycling.
• Thread Design: M11 × 1.5 mm external thread with an internal polygonal drive, allowing for accurate torque application and preventing cross‑threading during installation.
• Dimensions: Length of 137.5 mm provides the necessary reach to secure the cylinder head bolts through thick engine block material while maintaining a compact profile suitable for tight engine bays.
• Compatibility: Specifically engineered for a wide range of Audi, Seat, Skoda, and Volkswagen models including the A4 B5, A6 C4, 100 C4, 80 B4, and Cupra variants. The set is also suitable for other OEMs that use the same bolt pattern.
• Quality Assurance: Each bolt undergoes rigorous dimensional inspection and a final torque test to guarantee consistency across the entire kit.

Installation Overview

Installing the ELRING 804.250 set requires adherence to a strict sequence to ensure even pressure distribution on the cylinder head gasket:

1. Preparation: Clean all mating surfaces and verify that the bolt heads are free from burrs or defects.
2. Thread Engagement: Insert each bolt into its corresponding hole, ensuring the internal polygonal drive aligns with the torque wrench’s hex key.
3. Tightening Sequence: Follow a crisscross tightening pattern, applying incremental torque in stages (e.g., 20 Nm → 40 Nm → 60 Nm) to promote uniform clamping force.
4. Final Torque Check: Use a calibrated torque wrench set to the manufacturer’s specified value (typically 80–100 Nm for this bolt size) and verify that all bolts reach the target torque without over‑tightening.

Performance Benefits

• Enhanced Seal Integrity: The precise fit of the bolt head to the cylinder head gasket reduces the risk of leaks, maintaining engine compression and fuel efficiency.
• Durability Under Heat: The alloy steel’s high melting point and heat‑treatment process allow it to withstand prolonged exposure to combustion temperatures without warping or losing strength.
• Consistent Torque Distribution: The polygonal drive design ensures that torque is applied evenly, preventing uneven gasket compression that could lead to premature failure.
• Reduced Maintenance Intervals: By maintaining proper clamping force over time, the set minimizes the need for frequent re‑torquing or gasket replacement.

Maintenance and Inspection Tips

Regular inspection of cylinder head bolts is essential for long‑term engine health. Follow these guidelines:

• Inspect for visible signs of wear, such as thread galling or surface pitting.
• Check torque values after every major service interval; re‑torque if any bolt falls below the specified range.
• Avoid using damaged or deformed bolts in critical engine applications; replace immediately to prevent catastrophic failure.

Why Choose ELRING 804.250?

The ELRING 804.250 Nuts and Bolts combine proven engineering with meticulous quality control, making them a trusted choice for automotive technicians and enthusiasts alike. Their design ensures that the cylinder head remains securely fastened under all operating conditions, preserving engine performance and longevity.