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Tech Talk => Engine Mechanical / Electrical => Topic started by: angermgmt on September 11, 2016, 08:19:18 PM

Title: Alternator Issue
Post by: angermgmt on September 11, 2016, 08:19:18 PM
So just a heads up because I have never seen this before. My Gauge went to about 10.  Decided to pull it and take it down to be tested. Brand new battery by the way.  Started to loosens the fasteners and both halts of the alternator housing came apart. The bolts that kept them together we're gone. Now somewhere under the oil pan I guess. For safety now check those bolts...  B


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Title: Re: Alternator Issue
Post by: GT Jets on September 11, 2016, 09:54:08 PM
So just a heads up because I have never seen this before. My Gauge went to about 10.  Decided to pull it and take it down to be tested. Brand new battery by the way.  Started to loosens the fasteners and both halts of the alternator housing came apart. The bolts that kept them together we're gone. Now somewhere under the oil pan I guess. For safety now check those bolts...  B


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Are you talking about the four small bolts on Delco alternator?  You know what causes that?

GT
Title: Re: Alternator Issue
Post by: angermgmt on September 12, 2016, 07:14:02 AM
If I were to guess vibration or the belt was too tight.  But indeed tell me.


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Title: Re: Alternator Issue
Post by: GT Jets on September 12, 2016, 07:32:59 AM
If I were to guess vibration or the belt was too tight.  But indeed tell me.


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Axial vibration,  the belt is misaligned. Check three things.

1. Make sure the crank pulley is straight and does not oscillate.

2. That the two pulleys are perfectly in line with one another and tension is correct.

3. Check the thrust movement of the alternator and the crankshaft of the engine.
Title: Re: Alternator Issue
Post by: angermgmt on September 12, 2016, 07:39:06 AM
I had to reconfigure everything because the new housing was slightly different. I took a long socket extension bar and laid it across both pulleys to ensure it was straight. Belt tension is correct now.  I'll check the crank pulley next time out. Thanks for your help. B


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Title: Re: Alternator Issue
Post by: Bunger on September 12, 2016, 09:21:14 AM

Axial vibration,  the belt is misaligned. Check three things.

1. Make sure the crank pulley is straight and does not oscillate.

2. That the two pulleys are perfectly in line with one another and tension is correct.

3. Check the thrust movement of the alternator and the crankshaft of the engine.

How do I determine the correct tension? I've always just kind of guessed


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Title: Re: Alternator Issue
Post by: GT Jets on September 12, 2016, 09:32:25 AM
How do I determine the correct tension? I've always just kind of guessed


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You should be able to deflect the belt at the midpoint of the span about 2%of the span. In other words, at a 12" span you should be able to flex the belt about 1/4" with moderate pressure. This is obviously not the most accurate,  but will get you in the park.

A tensioning gauge is the correct way,  but who has time for that crap?

GT
Title: Re: Alternator Issue
Post by: el mojado on September 12, 2016, 01:27:49 PM
I use the twist-the-belt method. It should twist by hand about a quarter turn. But what do i know...
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