dephaser pulley?

[pt1]

when my mk2 172 is started from cold the engine sounds fine but once warm u hear a buzz/rattle at around 1750rpm as the revs rise then again at around 1750rpm as the revs drop,once warm the engine also sounds rough when idling,any ideas anyone? thanks

 

[Gray]

search function?

 

[pt1]

iv had a look but none seem to mention the rattle/buzz?

 

[mr.pink87]

Probably the dephaser on it's way into nirvana.

 

[montana]

the rough on idle could be normal as they seem to suffer from that. Have you checked the heat sheilds are all fixed and correct as this could be causing a buzz/rattle?

 

[pt1]

the buzz is coming from the top/cam belt side of the engine i think.the engine is sweet through the rev range but just sounds very rough when idling when warm

 

[Daniel]

I'm not a betting man but if I was, i'd say it was the dephaser.

 

[mark smith87]

It's fairly likely to be the dephaser pulley. My engine was whirring like it had a noisy alternator. I had the car into Birchdown for the cambelt and they said the dephaser pulley was badly worn and needed replacing. Since that was done the engine is nice and quiet again. Anyone who has a whirring noise on an RS get it checked. The dephaser seems to be a common fault on these engines. I've heard a few making the same noise.

 

[mark smith87]

The roughness when cold has gone as well since the dephaser was changed. It's transformed the way the engine responds and performs. If the pulley is badly worn it knocks the timing out and also the timing can't be set accurately due to the movement in the pulley.

 

[franx]

had some probs lately and the head had needed some work done to it. When remounted, after a while i could see oil laying on top of the rockercover. The mech used the wrong camseals and it's leaking oil from there.

Since this i have a "rumbling/vibrating" noise AND feel from the engine, starting around 2000rpm. Worried to say the least. Had contact with Sideways Danny off of here about this , explained the prob and he stated there is a very good possibility that the dephaser is playing up because of oil starvation, because of the leak through the camseal(s) .

Engine is acting rough around the moment this dephaser should be doing it's job. Sounds like the above mentioned.

Bugger that, in my case, all needs to be dismounted/replaced again (well belt+etc.) but i'm pretty confident it's the dephaser, especially after reading up on these "dephaser" threads on here using the search.

 

[mr.pink87]

What's been wrong with your head? I'd check the dephaser for play by removing the "cam caps" on the gearbox side and wiggling the inlet camshaft. Dephasers seem to dislike wrong oil grades and wrong servicing intervals.

 

[franx]

^^ arrrgh long story , short version:

Had a dead alternator , needed to ditch the car by the road as it was dead. Had a guy i knew from work pick up the car as i could'nt. He's a car mech. The next day i got a call from him telling that the timing was out, no compression, and with a scope he could see the inlet and exhaust valves open so bad news. (!!!!?????)

ANyway i think he thrashed the HELL out of my car and busted something. The timing belt had skipped, not busted.

So some valves were replaced, the pistons etc seemed fine.

this in very short is the story with me head . Very very much in doubt of my "friendly" mech/co-worker.

Oil: Motul 300V, changed every 6000k . i strongly believe that this is all happening to me because of one evening of leaving it in other hands

 

[mr.pink87]

Timing wouldn't be affected by trashing. Could have been a damaged aux belt (alternator not working). My first rule: Never give a F4R-powered Clio in hands you don't trust/have the knowledge to work on these engines. Did they use the correct tools/procedure for retiming the engine?
BTW: there is a note floating around that ALL valves should be renewed after a timing belt fail.

 

[franx]

ohwwww double bugger !!!! I would REALLY like to know about this note; changing all valves ?

To respond to your comment ; timing belts seemed to have skipped from very rough gearchanges ? Rough downshifts and/or the like ?

Anyway , to be sure i'm having the full cambelt + dephaser done all over for peace of mind and yes, by someone who knows F4R's

Still tell me about the "all valve change" thingy !

 

[mr.pink87]

The cambelt may be damaged by overreving the engine. If your mechanic did this, he's not a proper mechanic. There is some note from an engine specialist floating around (cba to search for it now) that the F4R engines like to drop valves after timing belt failure and not exchanging the whole set of valves.
If you need a proper mechanic, you are allowed to fly/"train" me in and pay me with your finest netherlandish weed

 

[franx]

hmm i might take you up on that

 

[thijnRS]

otherwise i will,
my 172 had his cambelt re-newed by a mate of mine.
but after the surgery i wasn't totaly happy. it feld a bit sluggish.
he did the 2 belts, but he left the waterpump, because it wassn't connected to either of the belts.
so he left it..
is that normal ?

 

[mr.pink87]

Waterpump is Aux belt driven. I'd change it aswell but not necessary. Did he change the whole Cam/aux belt kit incl. pulleys or just the belts? Correct tools used?

 

[thijnRS]

he's a mech at a universal garage, so i don't think he used the correct renault tool.
i know he said something about markings, so he could do it optical. but when the settings is a bit off, the car won't run atall wright ?


i think he changed the whole deal, i got the main belt in my trunk.. thats 2 rollers and the belt, the other i don't know.
the car feels a bit sluggish, and when i cruze at 2250 rpm i hear a high-tone..
maybe that sound is the exhaust or something, i will put the clio off the ground tomorow, maybe i'll see something thats wrong.

thnx

 

[mr.pink87]

Timing will be out if he did not use the tools. It's nearly impossible to get the timing correct with markings only as you can't tension the belt equally.

 

[franx]

Marthijn (from Ijmuiden)?

 

[sammyhale22]

If the Dephaser pully goes why don`t peeps just replace with Vernier pulleys??? When mine goes I will more than likely do this and just get the car mapped to suit. The Dephaser is very expensive and weak part of the engine.

Samuel

 

[sammyhale22]

The cambelt may be damaged by overreving the engine. If your mechanic did this, he's not a proper mechanic. There is some note from an engine specialist floating around (cba to search for it now) that the F4R engines like to drop valves after timing belt failure and not exchanging the whole set of valves.
If you need a proper mechanic, you are allowed to fly/"train" me in and pay me with your finest netherlandish weed

If an engine is in good shape over-revving won't hurt it. Mines bounced off the limiter plenty of times in its life and I'm at 102K now and going strong. There has always been this idea that over-revving damages engines, lack of correct maintenance and knowledge is what damages them.

 

[mr.pink87]

Over revving is not hitting the limiter. Over-revving is forcing the engine to over-rev by selecting the wrong (low) gear.
Dephaser pulley has a reason tbh. It's got something to do with emissions and idle but further explanations will be to complicated for you.

 

[LiamR172]

My 172 also makes a rattle noise, sounds like its coming from the dephaser area. My brother used to have a 182 and he said my car lacks power in the higher revs, could the dephaser cause this?

 

[mr.pink87]

Play in the dephaser can affect the timing which could result in a loss of power.