Alternator belt squeal. Tensioned correctly, gets loose (Page 1/1)
842m4SE SEP 01, 09:21 PM
On my 84 duke I've been having a recurring issue with belt squeal on startup. I recently replaced the previous belt that had glazed over, but now after having tensioned it, it squealed again on startup. Before, I had to keep tensioning every new day I wanted to drive it again, and it had gotten to the furthest point outward it could before I replaced the belt. When I replaced it, the belts looked to be the same length. When I replaced the alternator belt I noticed a bolt was missing holding the alternator to its mount, but I put a new one I and tightened it, thinking I fixed the problem. Looks like the same thing is happening again though... any ideas? I've heard tensioners are good but don't know of any for the duke.
842m4SE SEP 01, 09:22 PM


The bolt in question and the mount
theogre SEP 02, 12:57 PM
Tensioners are for Serpent belts. V-belts Hate bending backwards and will fail fast.

See my Cave, Serpent Belt
Most applies to V-belt too.
If you over tighten a new belt will fail and can make noise sim to loose belt.

Large alt bolt and nut are "locking" type for several reasons.
OE nuts was flange nut w/ "teeth" so won't get loose. I think is also "crimp" some so won't turn w/o a wrench.
Use Nylock nut w/ a ticker flat washer should fit it.

Small alt bolt is similar.
OE bolt Head should be same a above looks like Flange "Nut" w/ Teeth.

⚠️ Warning: Alt Belt squeal can be other things...
Bad Alt and/or Water pump.
Electric problems cause overloading alt and belt like Low battery or crap grounds and other wires can causes problems after starting or all the time.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

crashyoung SEP 04, 01:04 AM
I too used to have problems with belt failures and squeal.

Are you still using the original size alternator, or have you replaced it with a larger amperage unit?
If it is still the low output alternator, you can try the large output unit, but that may not cure it.
I installed a dual belt pulley system on my alternator, and that was the only thing that stopped the squeal.
Another nice thing, if I throw a belt, the second belt keeps it going as well as the water pump.
steve308 SEP 04, 07:14 PM
Have you cleaned the pullies? Pullies will become caked with dirt, dust and the rubber and fibers from the old belts. Brake clean is your friend along with a small wire brush.