Engine noise

[Mike Cordeiro]

Hello everyone,
I have been trying to find the source of an anoying engine rattle that comes from within the engine and only after it has warmed up. If you listen past the tappet noise you will hear a metal rattling sound.
The car has only 51.000 Kms (31.000 Miles). I have disconnected all belts and the noise persisted. Any help will be much appreciated.
Please see attachment for video.

https://youtu.be/okkIGAIWGX0

 

[jcarruthers2]

Hi Mike

My compliments on the very clean engine bay! I think I can distinguish an exhaust related rattle in the background.You have the warm air metal conduit for the air filter intake hose (for winter setting) attached to the short exhaust pipe running from the manifold to the downpipe. If loose, these have been known to rattle against the exhaust. Easy enough to take off, run the engine without it attached to see if it is the source of the problem.

 

[Mike Cordeiro]

Hi Mike

My compliments on the very clean engine bay! I think I can distinguish an exhaust related rattle in the background.You have the warm air metal conduit for the air filter intake hose (for winter setting) attached to the short exhaust pipe running from the manifold to the downpipe. If loose, these have been known to rattle against the exhaust. Easy enough to take off, run the engine without it attached to see if it is the source of the problem.

Thank you for your suggestion, I have checked it and it isn't it. It sounds like it but after spending many hours investigating I have conclusively excluded everything externaly. ( I use a broomstick to touch everywhere while the engine is making this noise) I have even used a cardboard pipe to listen in and zoom in on the source of the noise and it seems to come from the inlet manifold area. I have rebuilt this car myself and have exhausted all external possible sources. Could this noise be normal ?

 

[jcarruthers2]

Hi Mike

To be honest, I had to listen very carefully and I could not hear anything obviously unusual. If you are sure it is coming from the manifold area, have you checked the starter motor heat shield is not touching the underside of the manifold and rattling?

 

[Marktinniswood]

Hi Mike

My compliments on the very clean engine bay! I think I can distinguish an exhaust related rattle in the background.You have the warm air metal conduit for the air filter intake hose (for winter setting) attached to the short exhaust pipe running from the manifold to the downpipe. If loose, these have been known to rattle against the exhaust. Easy enough to take off, run the engine without it attached to see if it is the source of the problem.

Can you advise on my REN 5 issue

 

[mr-reno-139]

probably timing chain rattling as the water pump and alternator load is on the camshaft pulley and the chain is more stressed with this setup
engine out is the cure

 

[Mike Cordeiro]

Hi Mike

To be honest, I had to listen very carefully and I could not hear anything obviously unusual. If you are sure it is coming from the manifold area, have you checked the starter motor heat shield is not touching the underside of the manifold and rattling?

Thanks again, not it either. I have a lot of experience with engines and car restoration but I mus say , not with this particular back to front engines.
I had a Renault super 5 with the same motor but transverse and never noticed this noise. Thanks again.

 

[Mike Cordeiro]

probably timing chain rattling as the water pump and alternator load is on the camshaft pulley and the chain is more stressed with this setup
engine out is the cure

By exclusion of possibilities, of what could make such a noise inside this engine I came to that very same conclusion many months ago. "timing chain rubbing against the metal cover". But latter questioned my judgement because this engine is still brand new. It has genuine 51.000kms.
Maybe age got to it? Maybe the tensioner rubb pad came of?...or the tensioner spring has weakened ? Any thoughts ?

 

[AdamWilkes]

Although very young in miles, your car is old in time and the timing chain tensioner could have stuck, leading to a rattling chain without enough tension. Not sure what engine you have, but my 1983 1.1 had a stuck oil-pressure-actuated tensioner - sludged up. Unfortunately engine-out is the only way to access this, but it's not hard at all once you have found a strong enough beam to hang a small chain-block winch from !

 

[jcarruthers2]

Hi Mike

I have listened to it again, the timing chain rattle on an R4 has a distinct sound, when you pan your recording device to the back of the engine, I believe I can just about hear it . I bought an R4 once with very low mileage with a timing chain rattle. It had been standing for a long time with an oil pressure based tensioner as Adam Wilkes above mentioned, stuck in the same position for many years.

 

[Mike Cordeiro]

Thank you everyone for the valuable input. This 4L came from France 10 years ago and it has the 1.1 motor with the hydraulic tensioner. It did stand for many years.
I will pull the engine out in the near future and see what the issue is. I have pulled it out before when I restored the car, so second time is always easier...I hope :-)
I will share photos of what I find.