Cylinder Heads Archives - UnderhoodService
Valve Lifter Technology

Hydraulic lifters are precision-fit assemblies.

Subaru EJ25 Head Gasket Problems

Most of the EJ head gasket failures occur around the 100,000-mile mark and start as a slow oil or coolant leak.

Priming Concentric Slave Cylinders Before Installation (VIDEO)

These slave cylinders can be difficult to bleed if installed before they’re filled. Sponsored by LuK, a Schaeffler brand.

Cylinder Deactivation And Active Fuel Management (VIDEO)

Deactivating a cylinder requires specific technology. This video is sponsored by Auto Value & Bumper To Bumper.

Simple Engine Fasteners Actually Complex Engineering Systems

Fasteners act much the same as a spring due to the physics of stretch and rebound.

Cylinder Head Porting; Turning Air Into Power

Cylinder head porting can be a very effective way to improve the efficiency and airflow capabilities of any cylinder head.

Darin Morgan Joins BES Racing Engines

Longtime racing professional Darin Morgan has joined Guilford, IN-based BES Racing Engines.

Proper Procedures To Maximize Fastener Life

The right fasteners, installed the right way, can enhance the quality of any build.

VIDEO: Head Lift On Production Engines

Andrew Markel explores the damaging phenomenon known as “head lift” appearing in production engines, and how proper maintenance can keep it under control. Sponsored by Auto Value and Bumper to Bumper.

VIDEO: Thermostats And Oil Sludging

Andrew Markel explains how improper temperature control in the engine can lead to oil sludging in the valvetrain. Sponsored by MAHLE.

VW VR6 Head Gasket Replacement

The oddest things about the VR6 are that the narrow angle between cylinders allows the use of just one cylinder head for the six cylinders, and the timing chain is located between the block and transmission.

VIDEO: Diagnosing Head Gasket Leaks

Andrew Markel shows how to test if an issue is truly related to a head gasket leak and not something else. Sponsored by MAHLE.