Thread: Belt squeals
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Old 12-29-2014, 06:00 PM
Fridgewagon Fridgewagon is offline
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Join Date: Nov 2014
Posts: 13


The big problem is the cowl drains getting all clogged up as well as the blower box drain. If they aren't all gooped up, they work reasonably reliably on 700s. Usually you really have to blow them out carefully. All the detritus in there also holds moisture, which greatly increases the humidity generally, which usually makes for squeaking, corroding fan motor moving parts.

Theoretically, maximum alternator output is 55A, at minimum full output 1800+ (engine, not alternator) RPM, if no belts slip, with the right phase of the moon with brand new perfect wiring on a brand new car

2 or 7 series the belt wrap isn't excellent for the fan or Alt, accessory bushing dealies are often all dried up worn out junk, and at least with the gas Volvos, the Roulands or "Volvo" (I suspect the same) are 9.5mm width with the correct taper and actually grip the belt pulleys properly. The 10mm contis don't quite grab properly.

Theoretically, the accessory bushings extend belt or accessory bearing life, when they aren't all dried up junk, though one would imagine that unless on a cool weather car with zero oil leaks with them changed out or flipped position every other belt chang, more often than not they have the opposite effect.

Many modern diesel engines have a power pulsation/vibration dampener on the alternator pulley itself, which is quite logical; large reflected moment of inertia on the alt (or fan, but alt especially), with a heavy rotor and ~4:1 pulley size ratio, diesel engine with strong compression/power pulsations on long stroke heavy engines. Of course, these are largely to improve belt/other accessory part life. Of course, more often than not, the pulse dampener itself prone to failure. Usually they are a sort of rubbery/ratchet contraption, which has a small space in which to live within the alt pulley. Has a profound effect on how smoothly the belt(s) run when it actually works.

Benz solves this problem on later engines with a shock absorber and heavy tensioner. Expensive part when it wears out, not rebuildable on later ones, but often lasts the longest.

Volvo stuffed the already undersized accessory bushing dealies on the diesel with less than great belt wrap or bracketry...
...not to mention finding the correct # belts through the dealer or set of correct roulands for the diesels was always a PITA. I'm not looking forward to this.
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