M156 M159 Camshaft Adjusters Wear Problem
The Camshaft Adjuster wear problem is very common on the M156 adn M159 63 engine. All these engine will have this wear problem soon or later. The Camshaft adjuster where will give a rattle sound on start up.
What is happening is that the locking of the adjuster in 0 position is not locked anymore. This because of whear of the back plate. the plate where the pin is locked in is worn out so that the pin can slide out without oil pressure is pushing it over the edge. This wear will get worse if this not solved. And can give more engine problems over time
There are people that think that the wea out on the hole is normall and can be solve with turning the pin 180 degree’s. This can maybe solve the rattle sound for a short period but it will come back. So the adjuster needs to be change out for a new one.
When the pin is flipped. The adjuster needs to be assembled again. Everything is hold together with 5 M6 10.9 bolts. in the factory manual there is no torque value for this because there are change out normally and there is no overhaul kit or this from mercedes. the spec of M6 10.9 bolts are torque value 14,7NM. so don’t over torque them. there are people thinking onlin you need to give them 20 to 25 nm. This to much and you will over stretch the bolt this will can give a even more damage if the blt is coming loose or breaks.
The part number of the cam adjusters
Intake : A 156 050 30 47 replaced by A 156 050 36 47 price € 697,-
Exhaust : A 156 050 28 47 replaced by A 156 050 37 47 price € 690,-
if there are any questions about this subject or others just let me know
A pretty complete list of engine problems and most common can be found in this link to FCP EURO or below
Common Issues of the Mercedes-Benz M156 Engine:
- Crankcase Breather Valve – The crankcase breather valve fails in two main ways. The first and most common is that the diaphragm on the valve itself deteriorates. The other failure method is that the hose from the crankcase to the valve becomes brittle and develops cracks. Deterioration of this assembly leads to increased burning of oil, misfires, and heavy smoke from the tailpipe.It is common to have a fault code (P0170) that is for fuel trim.A general maintenance interval for your crankcase breather valve is right around 60,000 miles.To replace your crankcase breather valve, it’s necessary to remove your intake manifold in tighter engine bays such as the C63. This job should be able to be carried out in about thirty minutes. Although some use this opportunity to install an oil catch can system, we do not see many of these vehicles suffering from excessive oil in the manifold or sludge behind the intake valves.
We have an affordable kit that addresses all of the components you will need to replace when replacing your crankcase breather valve.
- Oil Leaks – The most common source of oil leaks on the M156 are the valve cover gaskets, camshaft solenoid cover gaskets, and oil filter housing gaskets. Valve cover and camshaft solenoid cover gaskets should be replaced concurrently. If these oil leaks are left unattended, they will damage peripheral components such as the alternator, drive belt pulleys, drive belt, air conditioning compressor, and transmission cooling hoses to name a few.
- Camshaft Adjusters – When the camshaft adjusters no longer hold hydraulic pressure, it will manifest itself first as a noise typically at cold start and progress to noise at any engine RPM cold or at operating temperature. This camshaft adjuster rattle is most prevalent on the intake camshaft adjusters and is observed mostly on engine startup.
- Drive Belt Pulleys – All of the pulleys on the Mercedes-Benz AMG M156 engine are a plastic design with a pressed on bearing. Although idler pulley failure is common across most Mercedes-Benz platforms, we recommend checking pulleys for failure symptoms at each oil-change interval. Pulley failure will damage the drive belt, and when that happens, the belt typically damages the coolant breather port on the thermostat. If you let that happen, you will have to replace a thermostat, and thermostat breather line in addition to the drive belt components.
- Cylinder Head Bolts – Most Mercedes-Benz AMG M156 equipped models (up to model year 2012) have cylinder head bolts that have the propensity to break,allowing coolant to enter the combustion chamber. Early warning signs include a low coolant light, misfires, and a check engine lamp. We recommend all engines equipped with the older design bolts be updated. The cutoff for engines not affected by this design flaw is serial number 60-060658.
- Camshaft and Hydraulic Lifters – Camshaft replacement should be considered a regular maintenance task as most camshafts show wear failures around 100,000 miles. Wear occurs most commonly on the left and right intake camshafts and if left unattended, the cam lobe will eat through the hydraulic lifter. Frequent oil changes, using the correct oil viscosity for your climate, and including an anti-wear additive with oil changes are all measures we recommend to protect your engine. Additionally, higher mileage engines should have their oil sent out for analysis periodically or the valve covers should be removed and camshaft lobes inspected for signs of wear.
- Intake Manifold Failure – The intake manifold on the M156 is constructed of a cast magnesium alloy, contains an adjustable length runner assembly, and houses the engine’s twin throttle bodies. The center mounting plate that houses the throttle bodies deteriorate causing rough running particularly at idle.