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Discussion Starter #1
I tried to start my 308 this m

I tried to start my 308 this morning and was shocked to hear a loud screaming noise when the engine was revved. If I let up on the gas pedal the noise died down but as soon as I accelerated again, the noise came back. I did not have enough time to look into it..is it a belt, a compressor, (not the water pump, just replaced that with a new one)...what on earth can it be? It is a 1979 308 GTS carburetted model.
 
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Discussion Starter #2
>>is it a belt<&#6

>>is it a belt<<

It's not uncommon for the belts to require periodic readjusts...you know it's time when they make the noise you describe...

Regards, JRV
 
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Discussion Starter #3
Forgot to mention...it's b

Forgot to mention...it's best not to keep revving if possible until the belt has warmed up and gained back it's adhesion abilities as making them squeal hardens & polishes the surfaces reducing friction even further.

Regards, JRV
 
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Discussion Starter #4
Best check to make sure there

Best check to make sure there is no oil spraying around on the bottom end of the belts. If there is don't drive it as it could be a bearing failure.

Regards, Grant
 
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Discussion Starter #5
Now that I have shelved my 512

Now that I have shelved my 512 BBi till I get the fuel distributors back, I have redirected my attention to this problem. It does not appear to be a belt that is squealing..it may be an idler pulley or the A/C compressor perhaps? How can you tell? I have removed the rear wheel and the the cover to access the area where the water pump, alternator etc... are...but cant seem to isolate the squeal. Help please???
 
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Discussion Starter #6
Coach,

they way I isolate n


Coach,

they way I isolate noises is with a "Mechanics Stethescope".

Regards, JRV
 
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Discussion Starter #7
If not a belt then it must be

If not a belt then it must be a bearing. I would first verify that you have correct belt tension, a shop manual helps here. If that's okay then check the belt(s) for any fluids on them, if okay, then loosen the belt and check for slop in the accessories or tensioner bearings. My guess it is the belt either being loose or it's time to change it. Maybe when the water pump was changed some "foreign" substance was deposited on the belt?
 
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Discussion Starter #8
actually jeff, when I replaced

actually jeff, when I replaced the water pump with a new one, I also replaced the belt with a new one...And the tension seems ok, dont really know how to measure except with the thumb pressure test...and when I replaced the pump, it did not squeal. Decided to do that a couple of weeks later. I will check for "slop" at the accessories or tensioner bearings...thanks. JRV, I have a doctor's stethoscope...would that work?
 
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Discussion Starter #9
Coach,

Well, same principal


Coach,

Well, same principal, except that a Mechanics Stethescope has a long metal probe instead of a flat . This enables one to keep their face out of moving parts to insure a visit to the emergency room doesn't spoil the moment {
}

That said, yes any listening device can pick up noises. An old trick is to simply use a very long screwdriver, tip held in place on engine, and placing ones ear on the handle. The long blade transfers the noises.

Regards, JRV
 
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Discussion Starter #10
Hi Coach,

JRV is talking a


Hi Coach,

JRV is talking about fundamentally the same principle. Here's a link to the first one from Google search:
http://shop.store.yahoo.com/joeztools/mecstet.html

The tool you want to check belt tension is a Gates Krikit belt tension gauge part #91107/7401-0071 available at Carquest for about $10 (this is the tool specified in your service manual). New belt will be tensioned slightly more than "run" belt.

Shoot me an email at [email protected] & I'll email you an instructional article on checking belt tension wrote up a few months back.

According to my workshop manual, your 308 also has 2 belts: alternator/WP & AC compressor. A thought (have done this on other cars to isolate belt/bearing noise, not on F-car): remove belt, run car *very briefly* see if noise persists. If not, you've narrowed down to one circuit.

Carl
 
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Discussion Starter #11
some of the solutions in life

some of the solutions in life require just some common sense. Thanks.
 
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Discussion Starter #12
some of the solutions in life

some of the solutions in life require just some common sense. Thanks.
 
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Discussion Starter #13
well, I tried loosening the al

well, I tried loosening the alternator to remove the belt...unfortunately, the second bolt on the laternator is almost in accessible. I had the car jacked up, remove the plastic fender undercovers, was able to loosen the bottom alternator bolt but ONLY FERRARI can design a car where the second bolt has to be accessed from behind the alternator, inaccessibly (without removing heat shields and a big pipe) and it is so irritating, when you're trying to solve one problem as in which belt or bearing is screaming at you...and now you have to figure out how to remove the belt. Grrrrrr!!!!!!!!!!!!!!!
 
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Discussion Starter #14
If you are talking about the t

If you are talking about the top bolt connected to the bracket I used a crowsfoot on a short extension to the ratchet.
 
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Discussion Starter #15
I agree, a Stethascpoe is the

I agree, a Stethascpoe is the way to find the source. One option it may be is a tired throwout bearing. as the lube dries out they are noisy until warmed up sometimes.
I'd check first if the noise seemed to be coming from the garage door area, I have heard noises like that before, LOL
 
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