CRD Timing chain.

[Brit30-06]

Hi lads.

I have a rattle noise coming from front of engine. I am wondering if i have a timing chain issue. I have looked down the oil filler hole to the tensioner and can see a hole in the plunger. Some internet sources state that this means it is at the limit of its travel. Is this correct?

My Engine is maintained meticulously and i would be very disappointed if i had timing chain stretch.

Mileage is 104,000 miles.

Thanks.

[Clarky]

Personally I think the mileage is too low for a stretched chain.
I would start with the chain tensioner first,
If that doesn't sort it you have wasted nothing as you would fit a new tensioner when you replace the chain anyway.

I know of one engine that the chain was rattily as so they added some AW10 Antiwear in an temp to silenced the rattle, that was a few years ago now and to my knowledge it is still running fine. At a guess I would say their tensioner was binding and the AW10 helped free it up, not an ideal solution but I don't know of any magic oil additive that can tighten a loose chain so the tensioner was probably the issue.

[Brit30-06]

Originally Posted by Clarky

Personally I think the mileage is too low for a stretched chain.
I would start with the chain tensioner first,
If that doesn't sort it you have wasted nothing as you would fit a new tensioner when you replace the chain anyway.

I know of one engine that the chain was rattily as so they added some AW10 Antiwear in an temp to silenced the rattle, that was a few years ago now and to my knowledge it is still running fine. At a guess I would say their tensioner was binding and the AW10 helped free it up, not an ideal solution but I don't know of any magic oil additive that can tighten a loose chain so the tensioner was probably the issue.

Hi Clarky.
Thanks for helping.

Have you heard that if you are able to see the hole in the tensioner that it is out of adjustment?



I am with you on the mileage. It seems low miles for the om642 to have timing chain issues particularly with a well serviced one.

Next time you are under the bonnet could you have a look at your tensioner and see if you can see the hole machined through it please? Sometimes the plunger has turned 90 degrees so obviously then you cant see it even if it's there.

[Brit30-06]

Hi Farwest.
Thanks for helping.

As far as i was aware the timing chain on the om642 should last the lifetime of the engine and is not a service item. Your position of changing the chain at 80,000 miles is new to me.It is a major job to have done, not like changing a belt.

I am always prepared to examine any preconceived ideas though.

[Clarky]

Had a look at my 2 engines, Spare has been sitting forever so tensioner is retracted.

After sitting overnight my tensioner is retracted on the daily driver so nothing to see there but once I start the motor the tensioner fills with oil within say 15 seconds and extends.

Photo's aren't great but here. I think that's the hole just visible on the right side on the lower photo. kind of hard to tell.
Cold


After starting


Video link for engine sound
https://photos.app.goo.gl/2eGgSDjajnKR671U6

[Clarky]

My Daily driver is at 300,000km (about 187,000 miles)

[Brit30-06]

Originally Posted by Farwest

Hi Mate...Im 100% sure 'Clarky' has more experience and knowledge of these things than I do...I have been 'accused' of over servicing all my life...its a 'sea going' thing I think...replace it before it takes a 'dump' mentality...the benfits of the knowledge and experience of the people on this forum far outweigh my 'thoughts'... more than happy to 'absorb' knowledge and in doing so save a few bucks...my background is Drag Racing...HIGH REVS...and Marine..no parts stores out there !...soooo...I err on the side of caution...LEARNING from the experts always enhances our knowledge...and an expert...Im definitely not !

Hi Farwest.
I too have been accused of over servicing more than once . My engine oil is changed twice a year. Most i have ever run is 5000 miles on one oil change in the six years i have owned it.
Transmission fluid was done 21,000 miles ago. Just got hold of some Ravenol ATF+4 to do another change.
Diffs and transfer case every couple of years.

This is a Forum. Its very nature is to be a place to exchange and discuss ideas and opinions. There are some really smart lads on the site. Also you are correct, Clarky is a top bloke who knows his stuff.