Why does my Mercedes Benz oil cooler keep leaking?
While this simple design does a great job of helping control the engine oil temperature it has a tendency to develop leaks over time. This is usually caused by the seal drying out and installing a new seal usually solves the problem.
How to drain and flush a Mercedes Benz oil cooler?
Please see our article on coolant drain and flush. Begin by removing the front engine cover (red arrow) by pulling it straight up and off and the left side air duct (yellow arrow) by compressing it in and off the air filter cover. Please see our article on engine cover removal for additional assistance.
Where is the oil cooler seal on a Mercedes?
When purchasing oil cooler seals always get the factory PURPLE color seals that are made of Viton. The older or aftermarket orange seals will leak much sooner. Unfortunately, the oil cooler is located at the bottom of the middle of the engine “V” design. It is underneath intake manifolds, EGR equipment, coolant lines and the turbocharger.
Why is the oil cooler on my Sprinter van not working?
Sprinter van engines built the same years have less issues with the oil cooler seals perhaps because their engines are open and dont have that decorative trim over the engine. That Wikipedia link above confirms my suspicion that heat is causing premature seal failure on 2006-2010 OM642 engines.
What causes an oil cooler to leak on a Mercedes?
Once the seals start to leak slowly the rate of leak will increase very fast. You may not initially get oil stains when parked as Mercedes models come with a fairly large undercarriage cover (aka belly pan) that can collect a significant amount of oil before it leaks over.
Can a diesel engine have an oil cooler leak?
The Achilles heel of this engine, unfortunately, is the oil cooler seal design. We’ll go over which vehicles are affected, the signs and symptoms plus let you know what to expect on a repair. All models that were equipped with the 3.0L V6 diesel engine, engine code OM642, can be affected by this problem.
Why does my Mercedes diesel engine not start?
However, if the engine is not running correctly automatic regeneration will not be started. Some of the possible causes are a faulty temperature sensor, swirl flap motor or EGR valve. Also, make sure you only use approved engine oil. Wrong engine oil can cause excessive soot build up.
Is there a problem with my BlueTEC oil cooler?
I have a 2014 ML350 Bluetec with 35k miles on the odometer. MB recently changed the oil cooler (under warranty) to repair an oil leak. It’s not a good sign. Given the model year, I assume my vehicle had the new oil seal o-rings.