Coolant Leak From Front Right Side Of BMW M52TU Cylinder Head – UnderhoodService

Coolant Leak From Front Right Side Of BMW M52TU Cylinder Head

Cylinder heads with a machining flaw (hairline crack) may have been installed on M52TU engines in production on a limited number of vehicles.

Situation:
Cylinder heads with a machining flaw (hairline crack) may have been installed on M52TU engines in production on a limited number of vehicles. The machining flaw (if present) is located in the front right side of the cylinder head and will cause a coolant leak in the area of cylinder 1 as shown in the illustration (Figure 1).



Correction:
Only if a customer complaint is received and a coolant leak is verified coming from the area shown in the illustration, should the cylinder head be replaced, according to BMW.


Procedure:
Replace the cylinder head and replace all valve stem seals as outlined in the appropriate repair manual (repair group 11 sections U 12 100 and 11 12 503). 

Some or all of this information was provided by the Automotive Parts Remanufacturers Association (APRA). For more information on technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.

You May Also Like

It’s Got Spark!

Why can’t you trust some spark tests?

You have probably seen some reality TV shows where the “builder” will pull a spark plug wire to confirm they have spark. This is one of the most misleading tests for the ignition system. If the spark plug produces a spark, the spark is at 14.6 psi (normal air pressure at sea level), not 170 psi or more inside the cylinder during the top of the power stroke.

Diagnosing Intercooler Boost Trouble Code P0299

The criteria for setting the code is very basic.

Honda Electronic Throttle Body Service Tips

Using care and following OEM procedures will help you to avoid unnecessary parts replacement and comebacks.

Why Alternators Are Subject To Ripple Voltage

The alternator produces an AC current that must be converted into DC current by way of a rectifier.

Belts and Pulley Alignment

A misalignment of the plane of the belt can occur when a pulley is not parallel to the other pulleys on the belt drive system.

Other Posts

Diagnosing Misfires

What if there are no codes and a misfire is intermittent? This is where it gets complicated.

Lifter Deactivation

The area of contact between the lifters and cam lobes is the highest loaded surface inside an engine.

Alternator Testing For No Charge Conditions

Many alternator problems turn out to be nothing more than a bad connection at the alternator or a bad wiring harness.

Understanding Coolants

All-season coolant used inorganic acid technology and worked great for almost 30 years.