Squeal Diagnosis Help

I am not too good with electrical stuff.

Dodge 318 motor; either belts or alternator is squealing on startup.

Squeal is very loud and intermittent. When squeal is happening, alternator gauge bottoms at full charge, then when gauge returns to more normal setting, squeal goes away. IOW: squeal-->gauge bottoms max charge, no squeal--->gauge returns to more or less normal, midrange indication. Gauge and squeal vacillate till engine warms up and gauge returns to normal and squeal goes away.

Is this bad bearing? belts out of alignment? bad voltage regulator? bad alternator? Which?

Thanks for any good help.

Reply to
herman
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Depends on what kind of vehicle this 318 is in and the year but...

When you start the car the alternator immediately goes to work recharging the battery to replace the energy the starter just drained off. You are pretty much running max load on the alternator so the belt is really working to turn the alternator.. a little worn or loose belt slips. The belt squeals because it is slipping. With just a little slipping the belt gets glazed and slips even worse which causes more glazing and on and on on. If a belt has been squealing best bet is to replace it and use some steel wool to clean up the pulley.

If this is an older car that you can manually tighten the belt on then replace the belt and make sure it is tightened properly.

If this is a newer car with a serpentine belt and automatic adjuster replace the belt and see if the problem is resolved. If the problem still exists then the automatic tensioner may be weak and in need of replacement.

If this doesn't fix the issue get back to the group and hopefully someone smarter than me will come along with more ideas. Don't let that new belt keep squealing though or you will have to replace it all over again.

Steve B.

Reply to
Steve B.

I suspect you have it the other way around. It's the slippping that is causing the meter to move.

--scott

Reply to
Scott Dorsey

Thanks to you and Steve for the replies. What I cannot figure out is why the noise is intermittent and disappears when the gauge needle drops back to normal and appears when it bottoms at full charge.

Mike Romain wrote in news:469b86f4$0$23125$ snipped-for-privacy@unlimited.newshosting.com:

Reply to
herman

Mine only makes noise when it is slipping which shows by the needle being in the wrong place.

This normally only happens right after a start up when the alternator is called on to recharge the battery from the start draw.

You mention 'bottoms' at full charge. Normally when a needle 'bottoms' it is at 'low' charge. The top of the gauge is normally full charge....

Mike

herman wrote:

Reply to
Mike Romain

What do you mean by 'bottoms at full charge'? Does the needle go all the way to the right or all the way to the left?

When the belt slips, causing the squeal, the alternator is probably not turning or turning slowly so that the charge rate drops. When it's not squealing, it's turning normally so the change rate is normal.

Or, a high charge rate causes the alternator to need more power from the belt but the belt is too loose to deliver it so it slips, causing the squeal.

Your alternator belt is probably too loose and/or worn and/or you alternator is binding. Take it to a mechanic and have it diagnosed. We can't hear the noise or look at the belt from here.

Reply to
M.M.

mine did that when i would turn the AC on, the belt would squeal and the charge would stop...when i turned off the AC, things would go back to normal.

turned out to be the tensioner pulley was going out. of course, this is assuming when you say bottoms out, you're saying the charge stops.

Reply to
nanook

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