vinkodex.Timing chain: the pulse wheel shifts, and the chain stretches with it
Typically between 100,000 and 150,000 km. It does not show up on every car.
critical
severity
between 100,000 and 150,000 km
mileage
2
sources
2 sources next to the write-up.
The fault
How you spot it
The service life of the timing chain on this engine is not outstanding: it has to be replaced between 100 000 and 150 000 kilometres. The stretching, however, is accelerated by another part, and that is worth knowing.
The pulse wheel is press-fitted onto the camshaft, and it shifts a little with every start. That shifting significantly speeds up the stretching of the chain.
The symptom is difficulty starting, which can grow as far as complete failure. The engine starts hard when cold, and as the valve timing drifts it loses power.
The repair is therefore not just the chain: the stretched chain and the faulty pulse wheel have to be replaced together. If only the chain is renewed, the cause stays in place and the next chain stretches the same way. So look for both of them on the invoice.
On engines built before 2014 the phase regulators also failed quickly and started to crack. The maker revised them, which pushed the fault later, but did not eliminate it.
Which model
Who it affects
The card opens the generation, the engine or the transmission.
Engines and transmissions
Engine
M270DE16AL
Engine
M270DE20AL
vinkodex.Checklist
Timing chain: the pulse wheel shifts, and the chain stretches with it
What you would check for this fault. Take it to the car.
Before you buy
Checklist
What you tick stays on this device only.
Sources
How we know
Silnikologia.comSilnik Mercedes M270: dane techniczne, opinie, problemy i tuningSilniki benzynowe z serii Mercedes M270, produkowane w latach 2011-2019, były montowane w pojazdach z silnikami montowanymi poprzecznie, takich jak Klasa A i
What BreaksMercedes-Benz B-Klasse W246 — All Engines, Problems & Buying Guide (2011–2019)Mercedes-Benz B-Klasse W246: 38 common defects and weaknesses. 5 engines (M270DE16, M270DE20, OM607, OM651DE18, …), 90–211 hp. Reviews, durability and buying advice 2011–2019.
Information, not an expert opinion
We write the descriptions, and we put the source next to them. A person reviews them before they go out. They are still information, not a technical expert opinion.
- A fault on the list does not mean the car you are looking at has it.
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