Timing chain query

[LostKiwi]

The cold start rattle videos are a good example of the noise.

Though I wouldn't be too concerned with a rattle after a 2 month layover.

 

[alexanderfoti]

Though I wouldn't be too concerned with a rattle after a 2 month layover.

No absolutely not. Good point about the sitting time actually.

 

[Robuk22]

Quote Though I wouldn't be too concerned with a rattle after a 2 month layover. quote

Actually, I didn`t get a rattle after the layup, perhaps it is because I have never activated the stop/start function.

Quote It isn't the tensioner that's the problem it's the worn sprockets and chain that put the tensioner at the limit of its travel. Quote

Perhaps it is the worn stretched chain caused from thousands of extra stop/starts riding up the teeth of the sprocket and wearing said teeth, be interesting to check when this problem occurs whether the stop/start function has been regularly activated or not. At the present time my engine is rattle free even though I have increased the power on my 180 cgi engine from 156bhp to 200bhp with a UK Bluespark tunung box.

 

[alexanderfoti]

Quote Though I wouldn't be too concerned with a rattle after a 2 month layover. quote

Actually, I didn`t get a rattle after the layup, perhaps it is because I have never activated the stop/start function.

Quote It isn't the tensioner that's the problem it's the worn sprockets and chain that put the tensioner at the limit of its travel. Quote

Perhaps it is the worn stretched chain caused from thousands of extra stop/starts riding up the teeth of the sprocket and wearing said teeth, be interesting to check when this problem occurs whether the stop/start function has been regularly activated or not. At the present time my engine is rattle free even though I have increased the power on my 180 cgi engine from 156bhp to 200bhp with a UK Bluespark tunung box.

On the 651 diesels, they get affected earlier when fitted with stop start.

The 271 engines are affected in the same way even without stop start.

Low rpm and stop/start puts a lot more wear on the system as you say.

 

[Robuk22]

quote The 271 engines are affected in the same way even without stop start. quote

Some are suggesting the earlier timing chain failures are due to the introduction of the turbo in those M271 engines.
If those 651 turbo diesels are failing earlier when fitted with stop/start then this appears to point to the stop/start system and not the turbo as the main culprit.
I never liked or used the stop/start system from the get go therefor I have probably inadvertently lessened the stress on my cars timing chain and hopefully lengthened it`s life.
Thanks Alexander for your input, it`s only from independent Merc repairers like yourselves that the actual cause will be revealed.

 

[LostKiwi]

quote The 271 engines are affected in the same way even without stop start. quote

Some are suggesting the earlier timing chain failures are due to the introduction of the turbo in those M271 engines.
If those 651 turbo diesels are failing earlier when fitted with stop/start then this appears to point to the stop/start system and not the turbo as the main culprit.
I never liked or used the stop/start system from the get go therefor I have probably inadvertently lessened the stress on my cars timing chain and hopefully lengthened it`s life.
Thanks Alexander for your input, it`s only from independent Merc repairers like yourselves that the actual cause will be revealed.

Given a turbo has no mechanical linkage to any part of the timing chain I struggle to see how a turbo could ever be implicated.

 

[alexanderfoti]

M271 never had a turbo as far as I'm aware and OM651s always had a turbocharger. Given a turbo has no mechanical linkage to any part of the timing chain I struggle to see how a turbo could ever be implicated.

There is a version of the 271 with a turbo and supercharger. I agree though, it's not really related to the turbo. On the 271 it's a batch of timing sprockets not made to spec. On the 651 it's just because they aren't beefy enough!

 

[W245207]

He's probably referring to the low end torque you get with a turbocharged engine.

 

[LostKiwi]

He's probably referring to the low end torque you get with a turbocharged engine.

Again makes no (or little difference) as there's no direct link to the camshaft train.

 

[Robuk22]

Quote On the 271 it's a batch of timing sprockets not made to spec. Quote

What years, from when, to when, I thought those soft sprockets were early years, pre 2010.