Mondial engine trouble mechanical squeel

sounds a bit like a whining belt, does it disappear after a minute or so?

 

That doesn't sound like a belt-that's a screech. Water pump bearings?

 

Something that is turning outside the motor is rubbing on something metallic .. that would be water pump pulley, smog pump, belt tensioners, a/c ... did you drop a socket into the innards of your engine?

 

I have sprayed some aerosol belt dressing (WD-40 even) on the v-belts while the motor is running just to make sure. I have heard screeching, growling, and clicking sounds from the QV v-belts that sounded a like a metal noise. You can do that from the top of the motor or from under the car. You may need a flashlight to get a good view of the v-belts.

If you block up the rear of the car and remove the rear wheels and the fender access panels (just a few phillips screws) then start the motor, you may be able to locate the source of the noise.

I have also used a piece of heater hose as a type of stethoscope to locate motor noises. This could at least tell you which end of the motor the noise is coming from.

If you take the fender access panels off, you could remove the alternator, water pump, and A/C belt/belts, start the motor and listen for the location of the noise.

That would confirm if it was actually an alternator or water pump bearing, too.

Also, pull your motor oil dipstick and see if you see any minute (really small) metal filings in the oil. This might indicate a failed bearing somewhere in the motor.

Good luck,

Jerry



Good luck,

Jerry

 

Failed cam belt drive pulley bearing?

 

one of your accessory belts is slipping. Or your water pump bearing is sluggish and cant freely spin equal to rapidly increased engine rpm causing that belt to drag over it. First thing I would check

 

I had an intermittent squeal from my Alternator Belt.
A year ago during motor break in. Gave me a heart attack.

Hope you find your squeak.

 

Let the aux belt tensions off and hand turn the various pulleys, anything a bit tight ?

 

Not driven by the cam belt. Each item may have it's own aux belt. Remove them one at a time, and run for a few seconds to isolate the noise. Cam belt idler bearings do go bad as well. When is the last time they were changed ? That is something that I would worry about.

 

Thor,

The QV's had two variations of auxiliary belts.

Some used one belt and some used two, plus the A/C compressor belt.

The Ricambi America online catalog has a good diagram of the two variations.

All the aux. belts are driven by the crankshaft hub pulley. They are not connected to the cam belts or cam belt pulleys.

You can run the motor with the aux belts off for a couple minutes. The water pump will not be turning, so do not run it for long or the motor will over heat.

The cam belts or cam belt timing will not be affected by removing the aux belts and running the motor.

I have attached a couple pictures. On this 85QV, there is a belt (the belt running vertical with the idler/adjustment pulley) for the water pump. A different belt (the belt running horizontally) for the alternator. And, a separate belt (the belt running diagonally behind the alt and water pump belt) for the A/C.

You can remove the alternator belt by loosening the alternator adjustment and retaining bolt/nut. This belt is easiest to remove because it is the outside belt of the three.

You can remove the water pump belt by loosening the adjustment pulley retainer bolt. The alternator belt must be removed first.

It is unlikely that the clutch drive bearing on the A/C is bad, but if the sound is coming from that area when you run the motor you can loosen the compressor adjustment(not real easy) and release the belt to check the bearing while the motor is running. The clutch bearing turns even if the A/C is turned off. I have literally cut the A/C belt off when I had an A/C issue, because I didn't want to take the time and effort to remove the alt and water pump belt just to remove the A/C belt. I did have to take them off to replace the A/C belt, later.

If the noise is related to the cam or cam belts, or the cam belt drive pulley or a cam belt adjuster bearing you will be able to hear it more accurately with the other belts off and you can get closer to the noise with the fender access panels off.

https://www.ricambiamerica.com/car-diagrams/ferrari/v6-v8/mondial-group/mondial-qv/timing-system-controls.html

Good luck.

Jerry
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You are headed in the right direction. It is fun to learn more about your car and gives you more confidence in driving it.

Check out this link.

Replacing Ferrari 308 Mondial timing belts

There are others on FC that are good, too.

Jerry

 

Mmm sounds a bit like a cam belt drive bearing, I heard it on my 308 about 20 years ago, it's a bit of a sod to do.
However it might be a water pump or something easy.
As the guys said, remove all belts, buy a stethoscope and have a listen to where it's coming from.
Oh also check out 'the helidoctor ' channel on YouTube, he does belts and bearings and all kinds of things on Mondials.......he's me.

 

Ha ha yes he's me, as you can see I'd been busy in the early days of ownership. But, once the car is sorted it should run very reliably. We use ours all of the time and drive it fairly hard. It's a great car and I've had a few.....
Good luck and keep us posted.
Regards Bell 'thehelidoctor' ;-)

 

where are you at? Did you remove accessory belts one at a time to rule them in or out as the cause?