Funny Clunking sound from timing housing

[r33_racer]

Hey,

ive got a weird sorta clunking sound from the front timing housing area. Its more destinct from the exhaust side, as in you can hear it and feel it more accuratly with a stethascope from that side.

Originally thought it was a cracked retainer so had a look over the exhaust camshaft side and found no scoring or marks on the lobes and inspected the retainers as best as possible without removing camshaft..all appear to be in good condition. So only thing i can think of is it might be the idler tensioner for the belt...the bearing clunking every revolution.

the sound only becomes loud from about 1500 to 2500rpm after that it doesnt get any worse.

The car has low kilometres and is in extremely good condition. all other bearings in pumps and idlers run smooth. there is no sounds from bottem end or harmonic balancer...has anyone got any ideas of what it might be..maybe something ive missed. I will be looking in housing this arvo to inspect the idler.

Cheers.

[DioXidE]

harmonic balancer???

[Bobjones]

Is it a clunking or wearing sound. I would pull the belt off and inspect the idler and tensioner, they should spin freely with no sound.

I am unsure from not hearing it so I am stabbing in the dark...though with a little torch

[Josh]

My mate just bought an R33 with the same noise, in about the same rev range, the guy at the dealer was saying that it will go if he changes the timing belt... I personally wouldnt have bought the car, but the guy said he'd fix it.

Dont know how just changing the timing belt would get rid of the noise, but when we reved it in that range, we could feel the vibrations coming from the exhaust side of the timing cover, so yeh, could be an idler.

I will let you guys know if the noise goes after this guy piss farts around with it.

Good luck R33_Racer

[FATGTS-R]

Will be watching this with interest as mine just started doing the exact same thing last night in the exact rev range as well.

Sounds terrible, from in the ****pit I thought it was the gearbox from all the vibration reverberating through everything.

On the plus side, if the timing cover and associated gear has to come off I will throw some vernier gears in there.

[HR31_RB20DET]

Does it do it all the time (continuous noise) when in the certain rev range or only makes the noise when your back off the throttle?

[Josh]

Does it do it all the time (continuous noise) when in the certain rev range or only makes the noise when your back off the throttle?

In my mates car it is constant when you hold it at those revs. I thought it sounded terrible. At first I thought it was the turbo.

I really dont see how just changing the timing belt alone could fix the problem as the guy suggested, im pretty sure he aint touching the gears or idlers.

Still waiting for my mate to pick the car up to see if its fixed.. so will let you guys know then, How is urs going R33_Racer

[r33_racer]

umm no change in mine..still only in that range...i inspected teh tensioner and its fine all the bearings are smooth and not clunky. I did the same test on the other r33 and it made the same noise except it was smoother and quieter and wasnt as noticeable.

I was thinking it might just be a certain point where the engine starts advancing timing enough for a major change in noise and vibrations from the moving parts...cause once u past that point the noise isnt there and nor is the vibrations. I had the car partially tuned today and there were no problems with it and the mechanics there didnt say anything about it. So it could just be nothing...but i will be changing my timing belt soon anyway when i do new camshafts so i may know something new then.

[benl1981]

I have vibration if for example you put it in 3rd and try and go up a small hill at below 2000rpm even on very small throttle opening. Most cars wont complain too much..but not pull hard. My r33 has a lot of vibration.

I have put a new timing belt in and new idler and tensioner bearing but still about the same and couldnt see anything of note around there.

Im thinking maybe the big exhaust or one of the missing manifold studs might be causing it.

But as soon as it is over 2000rpm it is smooth as. So I just don't really lug it.

Would like to know what it is though.

[benl1981]

if anyone solves the low rpm vibration problem can they please post up the results.

thanks

[r33GTS-t-200kw]

i have the same thing, if i slowly take off from idle-2000rpm it vibrates. I put it down to being a heavy duty clutch as everything else is brand new

[otto]

Hey my car dont this the other day when i changed my cas i must have torqued it up to much cause the mounting bolts were making contact with the pulley (have hks adjustables and they sit a little proud comared to the std ones). anyhow i just filed the bolt back abit and now its fine.

[benl1981]

could that happen with a standard cas and cam gear?

[r33GTS-t-200kw]

if it gets worse then worry about it lol :Dj:

[Jordan]

broken timing belt tensioner = engine rebuild. I suggest getting it looked at properly.

[benl1981]

true. In my case though replaced with new ones etc, still a similar vibration.

It is worth looking at as timing belt could be loose etc and hitting timing cover.

Mine is correctly tensioned but still gives a bit of vibration at about 1500rpm under load.

[Josh]

My mate picked his R33 up and after the dude changed the timing belt, the noise i mentioned earlier is gone.. maybe that will solve ur prob... new timing belt

good luck mate

[shaund]

My mate picked his R33 up and after the dude changed the timing belt, the noise i mentioned earlier is gone.. maybe that will solve ur prob... new timing belt

good luck mate

You sure all this dealer(?) changed was the belt? Perhaps the tensioner was changed too as a

preventative measure by the mechanic? Depending on how good the reporting and level of internal

procedure is (as well as how slack sales people can be with info) it is always possable that this

could happen and you not be informed the complete story.

-Shaun

[Josh]

Yeh i dont know if they changed the pulleys too.. I wasn't there to ask specifics, thats just what the car yard guy said to my mate. Either way changing the timing belt and/or pulleys fixed the noise and slight vibration I felt from the timing cover. It is true that they could of changed the pulleys as a preventative measure, as they had just sold the car and promised the noise to be gone when it was due for collection and not said anything about changing them to my mate.

[FATGTS-R]

Well the timing cover was whipped off today and the vibration on mine ( RB20) was definately the bearing. Shining a torch in there revealed metal shavings from where the bearing has been chewing itself out and the belt itself was a lot looser than one would hope.

Looks like I found mine sooner rather than later. Hopefully those meatal shavings havent caused any further damage.