Metallic-like buzzing from engine

[mgaut]

Can anyone relate to this??

Using my extensive listening device (i.e. my ear) I've tracked it down to the passenger side, somewhere around the air intake/cylinder head (and probably not the alternator or aircon pump).

The best I can describe it as is a light tambourine rattling, which increases with rpm.

I appreciate the internet is no way to diagnose a noise, but can anyone relate to this ?

cheers

Mike

[Ballsy]

First thing i would check is to see if anything looks visably loose, then look for spanners/allen keys and double check everything is tightened!!
Like you say its very hard to diagnose the problem without hearing it in person

[mgaut]

thanks Ballsy

Given that I *THINK* I know where it's coming from, I guess I ought to start by taking the air box off on that side; just the allen key bolts holding it on ??

No sign of stray tools or loose bits so far.

Mike

[QuiteQuietCerb]

mike hi check if the airbox brackets are loose

[mgaut]

QuiteQuietCerb said:

mike hi check if the airbox brackets are loose

You'll have to give me a clue Kostas

[HarryW]

Loose bolt with washer rattling somewhere maybe . The fact it rises with revs would worry me slightly, although I haven't got a real clue as to what it is.
Take the front scuttle off under the screen and check the long bolts into the starter behind the big fuse, I've heard tell they can have a habit of loosening.

[marcus1970]

mgaut said:

Can anyone relate to this??

Using my extensive listening device (i.e. my ear) I've tracked it down to the passenger side, somewhere around the air intake/cylinder head (and probably not the alternator or aircon pump).

The best I can describe it as is a light tambourine rattling, which increases with rpm.

I appreciate the internet is no way to diagnose a noise, but can anyone relate to this ?

cheers

Mike

Yeah, I can. It's fecking annoying and I'm trying to solve it at the moment. I'm not sure it's exactly the same as yours, but have a look at this...

http://www.pistonheads.co.uk/gassing/topic.asp?h=0...

I've just taken the air con belt off, but this made no difference at all. My next step is to take the alternator belt off and see if that makes the difference.

Let us know how you get on.

MB

[Nefarious]

HarryW said:

Loose bolt with washer rattling somewhere maybe

That would be my first guess, closely followed by a spanner/socket/nut that's fallen down the last time somebody worked on it.

A good tip for finding rattles is to take your largest screwdriver, put the handle in your ear and touch the blade to various metallic parts. The one in direct contact with the rattle will sound significantly louder than anything else. If you've got hair long than a crew-cut, wear a hat to avoid getting caught in something (yes, been there, done that).

[QuiteQuietCerb]

Hi Mike, each airbox is mounted to the engine with 2 triangular brackets, one at the front and one at the back of the airbox, check if they are playing up. let me know if you are at home later on today, i will come by and we can have a look together

[mgaut]

Right, MIGHT be getting somewhere. Airbox removed and engine run (no revs applied as airbox removed).

Tiny blowing from front manifold, so bit of gum applied and waiting to harden.

Unlikely to have solved the problem, given that it sounded "metallic" but nothing else loose/missing.

Did find a circa 10mm hole in the back of the airbox though; seems strange. Is that the power restrictor that gets a bung fitted by the dealer after I've owned it a year ??

Mike

(Kostas;here all day but don't make a special trip out in this weather)

[mgaut]

marcus1970 said:

I've just taken the air con belt off, but this made no difference at all. My next step is to take the alternator belt off and see if that makes the difference.

MB

MB

Good luck; my ear tells me it's not alternator but under the passenger side airbox somewhere. I've yet to find a full set of Snap-on Sockets down there but I'll keep searching !!

[QuiteQuietCerb]

i ll come by later on with James, im not in the tvr as its waiting for the wheels to be refurbished

[mgaut]

Thanks for your time Kostas

Suspected blowing manifolds; and YES it's a metallic kinda sound.

[JensenA]

mgaut said:

Thanks for your time Kostas

Suspected blowing manifolds; and YES it's a metallic kinda sound.

They can be welded, so not necessarily a huge problem.

[FarmyardPants]

There's a jubilee clip on the passenger side that sometimes rests against the bulkhead and can buzz/rattle...

[Ballsy]

mgaut said:

Right, MIGHT be getting somewhere. Airbox removed and engine run (no revs applied as airbox removed).

Tiny blowing from front manifold, so bit of gum applied and waiting to harden.

Unlikely to have solved the problem, given that it sounded "metallic" but nothing else loose/missing.

Did find a circa 10mm hole in the back of the airbox though; seems strange. Is that the power restrictor that gets a bung fitted by the dealer after I've owned it a year ??

Mike

(Kostas;here all day but don't make a special trip out in this weather)

That 10mm hole should have a rubber hose comming out of it, my minds went totally blank to what its for tho lol!! Sure sombody will fill the blank.

[marcus1970]

Ballsy said:

mgaut said:

Right, MIGHT be getting somewhere. Airbox removed and engine run (no revs applied as airbox removed).

Tiny blowing from front manifold, so bit of gum applied and waiting to harden.

Unlikely to have solved the problem, given that it sounded "metallic" but nothing else loose/missing.

Did find a circa 10mm hole in the back of the airbox though; seems strange. Is that the power restrictor that gets a bung fitted by the dealer after I've owned it a year ??

Mike

(Kostas;here all day but don't make a special trip out in this weather)

That 10mm hole should have a rubber hose comming out of it, my minds went totally blank to what its for tho lol!! Sure sombody will fill the blank.

Barometric air pressure?

MB

[kojak]

Ballsy said:

mgaut said:

Right, MIGHT be getting somewhere. Airbox removed and engine run (no revs applied as airbox removed).

Tiny blowing from front manifold, so bit of gum applied and waiting to harden.

Unlikely to have solved the problem, given that it sounded "metallic" but nothing else loose/missing.

Did find a circa 10mm hole in the back of the airbox though; seems strange. Is that the power restrictor that gets a bung fitted by the dealer after I've owned it a year ??

Mike

(Kostas;here all day but don't make a special trip out in this weather)

That 10mm hole should have a rubber hose comming out of it, my minds went totally blank to what its for tho lol!! Sure sombody will fill the blank.

Isn't it for draining any excess oil that mite find its way into the airbox. Sure I was told this. Mite be wrong. Mine was blocked of cause it was 'whistleling' due to it being worn. Never had a problem.

[Ballsy]

marcus1970 said:

Ballsy said:

mgaut said:

Right, MIGHT be getting somewhere. Airbox removed and engine run (no revs applied as airbox removed).

Tiny blowing from front manifold, so bit of gum applied and waiting to harden.

Unlikely to have solved the problem, given that it sounded "metallic" but nothing else loose/missing.

Did find a circa 10mm hole in the back of the airbox though; seems strange. Is that the power restrictor that gets a bung fitted by the dealer after I've owned it a year ??

Mike

(Kostas;here all day but don't make a special trip out in this weather)

That 10mm hole should have a rubber hose comming out of it, my minds went totally blank to what its for tho lol!! Sure sombody will fill the blank.

Barometric air pressure?

MB

Yeah thats it, it goes to a wee box near the ecu

[Pistonmike]

Got the same sound with my 2ltr alfa 156.
again louder with revs. more so when moving then stationary.
prob manifold, i will check on friday. thanks for info
explains noise.