Can a dephaser collapse?

[Carson22]

As above.

My 172 had the belt changed (I'm led to believe) just before i got it at 78K. I have receipts for the belts but not a dephaser so i'm assuming it wasn't changed. After about a month the dephaser started making quite a noise under heavy acceleration.

Due to Xmas etc i haven't got the money to change them just yet unless its vital, car is on 93k now so the belt has only done 15k, I'm just unsure if the dephaser can collapse like a idler pulley for example.

Thanks

 

[2Damnsly Andy]

It's the dephaser that goes and causes the trouble iirc.

 

[Carson22]

As in physically collapses or just causes running problems?

 

[Dan519]

no, that's not the dephaser. It would take a long time (10s of thousands of miles) for it to be so bad you noticed it anywhere apart from at idle)

Another issue is much more likely IMO

 

[Adam G]

As Dan says, you can hear dephaser at idle. Basically sounds a bit like a diesel, mine's been doing it since I bought it in Feb and hasn't really got any worse in that time. I'm getting it done after Christmas. You can't really hear it in the car, so if you're hearing a noise whilst accelerating it's something else.

 

[Carson22]

But i have no history of it ever being changed so it has been on for anywhere up to 90k haha

I had it in Rentech when i used to be in Portsmouth and i mentioned it to them and they said they could hear it on idle but said it should be ok for a while but i'm driving to Germany in January so it collapsing is my worry cause i dont know much about them.

 

[Dan519]

it can't collapse. However, if you can hear it at high RPM from inside the car, you have worse problems

 

[Adam G]

They could go on forever on some cars, mines on 114k and doesn't bother me at all. I'm getting mine done because my belts are due. I would leave it for another 10k if I didn't want my belts done. It would be unbearable at idle before I felt it needed to be done. I really think your noise is something else unless the dephaser is really bad. Can you upload a vid so we can hear, maybe one with bonnet up at idle and then of your acceleration noise.

 

[Dan519]

*awaits clip of big ends knocking their tits off*

 

[Carson22]

That's what i thought but i put it down to the dephaser because its a weird intermitant fault, if i accelerate heavily and it makes that noise then i slow down to a round about for example, then on light acceleration it makes the same noise, which goes away after driving for a little bit, so i was thinking along the lines of the dephaser sticking at the high speed position (18 degree's iirc) ???

Sorry mate im in Germany until 29th and my car is in Newcastle.

 

[Dan519]

stop driving and get it looked at ASAP before you throw a rod out the side of the block

 

[Adam G]

*awaits clip of big ends knocking their tits off*

Or "I pressed record, gave it some whellie and it went bang and stopped lol"
Silly question but you have checked your oil haven't you?
Or is it a short knocking noise under hard acceleration, probably 1st to 2nd?

 

[Carson22]

That bad? :O haha

I've driven it for about 15k like that with no noticeable running problems, looks like my wallets about to melt! hahaa

 

[Carson22]

Or "I pressed record, gave it some whellie and it went bang and stopped lol"
Silly question but you have checked your oil haven't you?
Or is it a short knocking noise under hard acceleration, probably 1st to 2nd?

Yeah oil if fine mate, its not a knocking noise as such, i find it hard to explain, Its like a deep grunt as if its bouncing on a rev limiter but it isnt at max revs cause it can do it on initial acceleration aswell (It only does it when theres load on the engine) if you get what i mean, thats why i thought dephaser because i know they cause problems and its not a mettalic noise, i used to work as a mechanic until about 18 months ago and i never heard anything like this in the past but i never worked on anything with a dephaser/VVT so i assumed that its a new system im unfamiliar with so maybe that could be the noise, im scouring youtube at the moment to try and find a similar clip haha.

 

[Carson22]

Thats the closest i can get

http://www.youtube.com/watch?v=oF8fVDlqXuU

It makes a noise similar to that in higher revvs with abit more grunt, it only starts once you've given it some welly.

I'll get my own video when im home next week, but if anybody can give pointers for now that would be great

 

[Adam G]

Your symptoms sound more like a knackered engine mount (maybe dogbone one). Usually happens under hard initial acceleration. Dephaser usually makes the noise all the time, once engine is warm afaik. If it only happens when you're ragging the car, then you know not to do it.

 

[Carson22]

Your symptoms sound more like a knackered engine mount (maybe dogbone one). Usually happens under hard initial acceleration. Dephaser usually makes the noise all the time, once engine is warm afaik. If it only happens when you're ragging the car, then you know not to do it.

It was a thought because my exhaust also snapped at the flange just after the cat so i was thinking there could be excessive movement but its just that once it does it in high revvs then if i slow right down it will do it aswell, but not if im just driving slowly. so i was wondering if the dephaser was kicking in at high end then getting stuck if you get what i mean? Im possibly overthinking it but it just seems weird to only happen under those conditions, whee as i would have thought a Big end as mentioned above would have been a perminant problem. I think i'll check the mounts out aswell then

At one time i was all over this, ford and vauxhall was my area but being off the spanners completely for 18+ months has done its damage it would appear haha

Cheers for all your help mate.

 

[Adam G]

Maybe you need to get it on a ramp or ask Rentech to have a look.

 

[Carson22]

Maybe you need to get it on a ramp or ask Rentech to have a look.

Unfortunately i don't have access to any ramps and i'm not in Portsmouth anymore. Looks like im getting on my back in the dirt, if there's anything majorly up that i cant find then i'll send it to Alpine Automotive which is up my way apparently a Renault Specialist. I only want to put it in a garage as a last resort if i can do it myself.

 

[Adam G]

Oh yeah I see you've moved slightly up the road.

 

[Nmp1970]

If thats te noise its making its defo the dephaser pulley, I had it on my laguna 2 but drove it for over 2 years before getting rid.

 

[Carson22]

If thats te noise its making its defo the dephaser pulley, I had it on my laguna 2 but drove it for over 2 years before getting rid.

Its very similar to that, but it only happens when its been given some welly and under load, its fine on idle, can hear the dephaser slightly on idle but nothing like that video.

 

[marcushookdale]

see another pointless thread, people never ever fecking update or say what the problem was,

this buggs the fcuk outa me.