Date: Sat, 14 Jan 2017 09:32:56 -0800
Reply-To: Alistair Bell <albell@SHAW.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@SHAW.CA>
Subject: Re: Quickie alternator fix
In-Reply-To: <CY1PR20MB00293FC84E239CCAAFDC5D3BA07B0@CY1PR20MB0029.namprd20.prod.outlook.com>
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Right you are Dennis. But let me add a couple of clarifications.
I was totally chuffed with being able to get the alternator fixed and back in the van in such a short time. My local Napa is only about 10 min drive from home. And they had the bearings in stock.
Oh, and about my regret at not checking the lube in the bearings. I mentioned that they are no name bearings and I have seen other no name bearings with, less grease than what I thought was sufficient grease, in them.
The slip ring copper is indeed getting close to end of life. I had cleaned the copper up on the lathe just enough to take away any groove. And yup, the smaller (albeit slightly smaller) diameter rings may affect life of the brushes, maybe, brush and spring might be long enough to compensate.
I'm not sure if I will build up a spare alternator from the parts I have, or pick up a newer model. This particular 90A alternator model seems so simple and lots of them around. Certainly has been ok for me.
Cheers
Alistair
> On Jan 14, 2017, at 6:28 AM, Dennis Haynes <d23haynes57@hotmail.com> wrote:
>
> Yes I do love this. Here are some additional thoughts.
> The bearings probably could have been sourced for even less than NAPA. Since
> they were sealed both sides, they lubed and ready to go. No need or benefit
> to add more grease. They will last as long as they will last.
> You were lucky that the insert for the small bearing was still in place.
> When you turned down the slip rings on the rotor you also reduced the usable
> brush life a bit.
> Alternator whine can be produced from a number of things. A common one is
> that windings on the stator are now vibrating. Low voltage equipment lets
> you get away with a lot. Good motor overhauls usually include cleaning and
> re-dipping the windings in insulation varnish and baking to dry-cure. The
> also helps prevent future winding to winding shorts.
> At some point the woodruff was eliminated. Without it you have a
> self-tightening set up.
> As for asking a shop to do this your 1.5 hours is ~$160. Warranty? You're
> getting the boxed rebuild.
>
> Dennis
>
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Alistair Bell
> Sent: Friday, January 13, 2017 11:57 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Quickie alternator fix
>
> Dennis is going to love this :-)
>
> Alternator has been whistling the last week or so, getting louder every day.
> I knew what was wrong.
> Confirmed it yesterday, felt the play in the pulley (belt off).
>
> This alternator owes me nothing. It's the one that came on the 92 Jetta 1800
> I4 I put in my 82 westy back in 94. I've already replaced the brushes twice
> and the bearings once.
>
> I have a parts alternator in bits and pieces in the barn. I had cleaned up
> the slip rings on the lathe and I figured the rotor was good enough as a
> back up.
>
> Yesterday at lunch I went to the local Napa and bought replacement (2)
> bearings. They were no name bearings. Oh well, hoping they will last for as
> long as it takes me to get a spare alt together.
> I pulled the whistling alt from the van. Got it apart and and confirmed
> pulley end bearing shot.
> The the bores in the frame where the bearings sit were tight, no wallowing.
> The bearings were tight on the shaft. So it was just the bearing itself that
> had failed, worn out.
>
> I put the new bearings on the rotor that I had cleaned up ( btw, slip ring
> diameter was about 26.5mm). All went back together easily with only one "oh
> darn it" moment when I dropped the woodruff key.
>
> And back in van and back in service.
>
> Total cost was 26 bucks for the bearings, plus one and a half hours of my
> time.
>
> ( noticed my brushes were close to wear limit. I think I might try soldering
> new brushes as this particular reg is an adjustable one.)
>
> And after I had put it all back in van, and was mulling it all over,
> realized I should have pried up the rubber seals on the cheap bearings and
> given them some extra grease, or at least check if there was enough grease
> in them.
>
> Alistair
