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Discussion Starter #1
Because the Alfa season will come to an end in just a few weeks, I decided yesterday to drop everything and take the Spider for a nice spirited drive in the back country roads to admire the changing fall colours. About half way through the drive, tha car started making a strange new sound when driving on rougher roads or hitting bumps. Almost as if I had a 6 pack of empty beer bottles under the hood.

I do admit that I occasionnally (ok, most times) sustain myself with a "barley sandwich" while I work on the car, no empties have been found under the hood.

Having just checked the oil level I first suspected that I had not properly secured the oil filler cap but, that was not the case. Sadly, apart from sliding under the car to make sure nothing in the steering or suspension had become loose and render the car dangerous to drive, I did not have the chance to investigate any further. Car still runs and drives beautifully. Cursory inspection under the hood didn't reveal anything that had suddenly become loose.

Having recently installed Carello headlight covers, my next area to investigate will be the headlight buckets but, should these prove to be tightly secure as well, any other ideas where to investigate. Sound is really more "glassy" than "metallic".

Thanks for your input!
 

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How are the engine mounts? As they age they let the engine move more than it should. The fan can rub the shroud &/or the exhaust can touch where it shouldn't. Are there any heat shields under the floor? If they get loose they will rattle/vibrate - often moreso at certain speeds/rpms due to harmonic vibrations.

Or you could just turn up the volume on the radio...

I decided yesterday to drop everything and take the Spider for a nice spirited drive in the back country roads to admire the changing fall colours.
And where are the pictures? We likes pictures.
 

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Discussion Starter #3
How are the engine mounts? As they age they let the engine move more than it should. The fan can rub the shroud &/or the exhaust can touch where it shouldn't. Are there any heat shields under the floor? If they get loose they will rattle/vibrate - often moreso at certain speeds/rpms due to harmonic vibrations.

Or turn you could just turn up the volume on the radio...



And where are the pictures? We likes pictures.
Thanks for your input Eric. I will certainly investigate the engine mounts but this new sound didn't just creep up on me. One second it wasn't there and the next, boom, it's there!

BTW, the radio is the most useless piece of equipment I have installed on the car! I never tire of the Alfa canzone!
 

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Richard Jemison
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noise

check all the bushings on the sway bar mounts and end links. Shock bushings as well. Be sure bushing mounts are tight and not torn loose (chassis tearing).

Things like alternator mounts starter mountsing bolts abnything bolted on the engine or chassis.
 

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Although engine mounts indeed deteriorate over time, there often comes a tipping point when, as Eric observed, the engine becomes just low and loose enough that the fan will occasionally kiss it's shroud, producing a brief "zinging" sound, usually under the circumstances you described.

When you hear hoof beats, don't look for a zebra. It's very likely a very ordinary horse, just like the one owners regularly experience.

Best wishes.
 

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Discussion Starter #6
So I had a little time to investigate this further using some of your suggestions but, first things first, pictures.

FYI, the bottle of beer on the motor is a recent addition used strictly to help investigate the strange sound. Driver's side headlamp bucket was solidly attached and so were other tidbits such as alternator, coil, fuel filter etc. As you can see, the bottom of the fan shroud has been cut away by PO and fan shows no damage so, the fan is not rubbing on the shroud.
Motor mount on driver's side looks in good shape and since I can't readily see the passenger side one, I'll assume they are of the same age and thus, similar condition. But, upon inspecting the headlamp bucket on the passenger side, I noticed that I had lost the top screw to the round access panel. I quickly installed another one

Time for a test drive!
 

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that radiator shroud looks a bit chewed up at the edges.....you sure the fan is not touching it?
 

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Discussion Starter #8
Upon starting the car, the sound came back! No need to drive around or hit a bump this time.


Sounds more like a pulley rubbing against metal. I am now starting to suspect the motor mounts.

Anyone have a better explanation?
 

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To me sounds sorta more like a dry bearing: waterpump or alternator?

try taking off the fan belt to isolate the alt. and w/pump, then run the engine again (no problem to run it like this for just a moment) and see if the noise goes..
 

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Hard to tell and this is just a wild guess but it does appear as though the outer flange on the crankshaft pulley is unusually shiny as though it were rubbing on something..
 

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Hard to tell and this is just a wild guess but it does appear as though the outer flange on the crankshaft pulley is unusually shiny as though it were rubbing on something..

good spot! That is indeed unusually shiny!
if the engine mounts were worn that pulley would be scraping on the front swaybar.
 

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Discussion Starter #12
Dom, Paul, those are great ideas. Sadly can't check them out until later this week.

Thanks again to everyone who chimed in. You are all awesome and deserve a drink!
 

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Your driver's side motor doesn't look too bad and has probably been changed at some point. BUT, since the passenger's side mount can be a royal PITA to change, it's quite possible that when the PO likely changed the driver's side, they took a look at the passenger's side and said screw it, and figured that doing one was good enough.

Best regards,
 

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Discussion Starter #14
good spot! That is indeed unusually shiny!
if the engine mounts were worn that pulley would be scraping on the front swaybar.
Ok, couldn't resist. Took 2 minutes to check it out. I think we have a winner! Only the edge directly over the swaybar is shiny. Cheap (but laborious) fix.

Happy this happened at the end of the season! I guess I'll be finishing the season with the Fiat!

Thanks again!
 

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.........which also expains why the noise happened earlier over bumps!

well, that is a nice winter project, engine mounts! Do the trans mount at the same time and your car will drive much better!
 

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I vote for motor mounts as well. I think there is a reason why the DPO cut away the bottom of the shroud. That would be scraping long before the pulley on the sway bar.
 

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Discussion Starter #17
Well sadly I don't have a heated garage yet so, engine and transmission mounts are an early spring project!

This forum is so awesome!
 

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It was a horse, not a zebra :).
 

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Well sadly I don't have a heated garage yet so, engine and transmission mounts are an early spring project!

This forum is so awesome!
Yes. The shiny pulley flange was a great catch by Paul.

But before you tackle your motor mount R&R project next spring, a bit of advice: I suggest you soak all of the associated mount fastening bolts/studs/nuts/threads with a good rust dissolver/solvent for a day or two ahead of commencing disassembly. I use Liquid Wrench, but Eric and a couple of others on this BB recommend a 50-50 mix of Acetone and Automatic Transmission Fluid. Either way, it should be a requirement for that project, as the consequences of stripping or snapping off a motor mount stud are horrendous, and it seems to be a common occurrence.
 
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