1.6THP DSport - Rattle/knocking from belt assembley

[monkeynuts]

Quick out the traps there Nuts LOL

Not really its just terrible hearing about it and it seems the problem never goes away even after the alleged update fix etc

[Chris_Blue]

^ ^ Ketsbia's DS3 150 appears over 3 years old- Ive only seen 2 timing chain issues on here since March 2011 models (one benefit of being looking at the threads on here for so long)

[monkeynuts]

^ ^ Ketsbia's DS3 150 appears over 3 years old- Ive only seen 2 timing chain issues on here since March 2011 models (one benefit of being looking at the threads on here for so long)

Seems you could be as sad as me then

[Chris_Blue]

LOL. Was once dubbed "The saddest man in Amsterdam"
That expression was repeated all the way around Amsterdam for 2 days, on my Stag.Always laughing. All the lads were off their heads obvs
Happy days

[colganraz]

I wish all these THP issues would gain a permanent fix, shame as it is such a good engine bar the timing problems.

I think the timing has slipped on my engine very very slightly now.. i had a look at the timing gear online and saw the bottom crankshaft chain sprocket is held in position with what looks like a hub which bolts into place, sandwiching the sprocket using force alone to keep it in place to the crank, no wonder it slips!

I think they used this method opposed to a keyway to make it easier to change the timing gear, i dont see what it matters really i thought a chain driven motor would pass 100k before it needed changing anyways?

[Chris_Blue]

The earlier Mi....i THP engines still suffer with chain issues
Someone tell me how a metal chain stretches? Is it the links

[Jonbays]

As a cyclist I can tell you from years of experience with bicycle chains. What happens is the holes which the link pins go through wear on the tension side making the round holes in the slightly elongated, the rollers themselves wear two but more uniformly as well to slowly increase the effective pitch of the chain which then wears the sprockets into shark fin shapes. It doesn't take much wear at all as all the wear quickly adds up over all the number of links. When they are worn out its obvious as you can pinch and pull the chain up off the sprocket a small amount. The tighter the twists and turns the chain has to make the quicker it will wear so small sprockets like the one on the crank really cause the chain to wear fast.

The earlier Mi....i THP engines still suffer with chain issues
Someone tell me how a metal chain stretches? Is it the links

[Jonbays]

The design parameters of the Prince engine to reduce frictional loss meant that a heavier duplex chain which would spread the load over bigger and heavier sprockets with more mass etc would have resulted in additional friction losses despite the additional service life so they opted for a shorter service life lower friction design. Without VVT they might have been able to get away with it or perhaps on a lower revving engines with only two valves per cylinder. The timing chain was claimed as being better than a toothed belt in that it would last the full service life of the engine rather than having to be replaced at 100k service intervals. Clearly someone who designed this failed the math on the service life by underestimating the wear on the chain and sprockets from the VVT 4 valve Cam design rather badly.

[Chris_Blue]

Nicely explained Jonbays- so they should have stuck with a belt then

[Jonbays]

Well yes I think so having changed a couple of cam belts on Mazda's and Honda's they seem to have got it right. The toothed belt OHC four cyl engines they make seem much quieter and although its a faf to do every 100,00km it's not that hard a job.

Nicely explained Jonbays- so they should have stuck with a belt then

[Kieron]

What was the out come in this I have the same rattle in my ds3r fast i go faster it gets had new chain tensioner everything and it's still there grrr

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