Black dust near front of Alternator

[britinusa]

There's quite a bit of black dust near the front of the alternator. I wiped it off of the sound/heat proofing on the aft face of the lower steps.

I'm guessing it's from either the Alternator Belt which looks in pretty good shape, or it's from the alternator brushes.

Any suggestions.

Paul

[Dave Spencer]

Almost certainly belt wear.  This is very common (...I hope, since I have dust on mine too.)  If it's severe, have a look at alignment between the alternator pulley and the drive pulley.   

[Noah]

Another thing to consider is perhaps the engine insulation, behind the foil face, is/has deteriorated and causing the "dust"?

[Ron Hill]

Paul : Some "belt dust" will naturally occur, just check to make sure that it's not excessive dust (wear) due to poor alignment!!

To check alignment take a straight edge ruler and place it on the water pump pulley and extend it over to the alternator pulley.  The straight edge on the alternator pulley should just touch the ruler
If it doesn't match, then you need to play with washers on the alternator attaching bolt to move the alternator on that bolt - for or aft.

A thought

[britinusa]

Thanks everyone.

Ron, that sounds like the process to follow. I'll take a steel rule to the boat tomorrow.

The dust is on the surface of the heat sheild and on the front of the alternator. I'll vacuum it off and check the alignment.



Paul

[Stu Jackson]

Paul, take another look in the 101 Topics.  I posted a detailed discussion of how to align the pulleys, from Maine Sail's input.

This one

Universal M-25 & M25XP Alternator Bracket Upgrade & Alignment 101 IMPORTANT

http://c34.org/bbs/index.php/topic,7917.0.html

[KWKloeber]

There's quite a bit of black dust near the front of the alternator. I wiped it off of the sound/heat proofing on the aft face of the lower steps.

I'm guessing it's from either the Alternator Belt which looks in pretty good shape, or it's from the alternator brushes.

Any suggestions.

Paul

What type belt do you run?  Recommend a Dayco Top Cog for longest life.  JTSO

kk

[Roc]

Paul,
Check your alternator bracket.  It may be cracked and cause movement.   Although it was cracked and the alternator was rocking back and forth if you put pressure on it, everything was working, so I don't know how long it was like that.  Replaced the bracket and no more dust.  I changed the belt at that time also.

[Lance Jones]

One other thing to check is that the through bolts that hold the alternator halves together have not loosened. That happened to me last year. Thankfully, I caught it before much damage was done. I never thought to check that.