Hi guys

 

I've got a funny rattle coming from the engine...

 

I had teh cambelt changed a couple of months ago and about a week after it had been done it started to develop this intermittent rattle. The rattle's got progressively worse and is now there all the time.

 

It doesn't sounds metallic like tappets - it sounds to me more like a plastic rubbing on plastic noise, but a definite rattle. And it rises with the RPM.

 

I'm thinking maybe the monkeys at the Nissan dealer have put a belt back on or something and its rubbing on something else..? I though it might be the fan but the noise is defo coming from the vicinity of the engine block ...

 

Any advice much appreciated.

 

ED

hmmmm a bit vague, but get it checked out ASAP. could be as bad as a spun bearing. (i asked everyone under the sun and they all said -nah cant be a spun bearing ect.) if the noise rises with the revs then its mechanical. Really get it sorted out asap , rather than leave it to late and it cost you a fortune.

 

plastic noises wuold not rattle. Tappets you would not hear above revs.

Ed - does the actual frequency of the noise rise with rpms or does the loudness increase? Not sure why I'm asking but I've got a rattle that isn't detting, it's not the tappets (as Warren pointed out) but it sounds more like valve flutter like when a manual transmission is in too high a gear for the speed the car is going at and you press the accellerator. Mine's an auto though and tends to do it only in the top 2 gears. Having said all this, it does only happen when the engine is warmed up. Just a thought, could it be the PCV valves riccocheing because they are knackered?

 

This message is of absolutely no use - sorry ...

 

Dan

can you count the knocks at tickover? - I mean is it a really slow rattle? On my service records Nissan once botched a cam belt change and got it back a few weeks later with a cambelt knock to do it again. I can only imagine the belt got damaged while fitting and a strip was torn that then hits on something once every cambelt revolution which is much slower than once every engine revoltution cos its a long belt.

 

Could also be things like tensioners. Worth checking asap!

 

Does anyone know if its easy to get one of the covers off to inspect the belt condition?

i cant count the rattles - so it could be something to do with the belt being damaged and hitting something once a revolution...?

 

sounds more likely its the spun bearings though

 

im not gonna try and inspect it though, i'll book it in tomorrow it's due for a service anyway.

 

hopefully its not too costly. i might have to sell the car it if its gonna be loads- i still havent recovered from last time something went wrong (problems with it when it went in for a minor service cost 1100 squid). :( i will be gutted if i have to sell up.

 

oh well. such is life. its only a car isnt it? :confused:

 

cheers for your help, fingers crossed.

Originally posted by Danny

Ed - does the actual frequency of the noise rise with rpms or does the loudness increase? Not sure why I'm asking but I've got a rattle that isn't detting, it's not the tappets (as Warren pointed out) but it sounds more like valve flutter like when a manual transmission is in too high a gear for the speed the car is going at and you press the accellerator. Mine's an auto though and tends to do it only in the top 2 gears. Having said all this, it does only happen when the engine is warmed up. Just a thought, could it be the PCV valves riccocheing because they are knackered?

 

This message is of absolutely no use - sorry ...

 

Dan

 

Hi Dan

 

Its the frequency of the noise that increases with the revs, not an increase in loudness.

 

at, approx 3/4000 rpm the noise of the engine drowns it out.

 

it doesnt sound like valve flutter its a lot more defined rattle.

 

Ed

If you press the clutch in does it still make the noise?