Bosch Alternator sounds like it is full of crickets

I have been running the alternator on my 40 HP for over a year now.
Granted, I have to rev it a bit to keep up with traffic (when I care), but I
am wondering if the alternator is wearing out? At idle it makes a racket
that sounds sort of like a bunch of crickets. It dies down when I rev the
engine a bit. I don't get to hear my beloved fweem as much with that noise.
Is it a sign that the alternator is getting ready to malfunction, that it is
just "dumping" excess power at idle, that it is lugging... or what? The
battery is good.

TIA
--
KWW

" At idle it makes a racket
that sounds sort of like a bunch of crickets. It dies down when I rev
the
engine a bit."

A quick way to check the belt is to spray it with a bit of carb or
brake cleaner while the engine is running. If the squeak goes away then
it means the belt is slipping. I have had this problem in the past when
I degrease the engine, it seems that the degreaser causes the belt to
get glazed and start to slip a little even though the tension is fine.
One quick fix is to take a bit of wheel bearing grease and work it into
the sides of the belt over a section an inch or two long and then start
the engine. It should make the sound go away.

If that doesn't help, try grabbing the fanshroud and push/pull slightly
with the engine running. If the sound gets louder or goes away it means
the fan is rubbing. You can usually loosen the alternator clamp and
pull/push it and then tighten the clamp to remedy this. Another
possibility is a bad bearing in the alternator itself, however if it's
only a year old I would say that's probably not the source of your
noise.

Good luck.

Chris

KWW wrote:

> I have been running the alternator on my 40 HP for over a year now.
> Granted, I have to rev it a bit to keep up with traffic (when I care), but I
> am wondering if the alternator is wearing out? At idle it makes a racket
> that sounds sort of like a bunch of crickets. It dies down when I rev the
> engine a bit. I don't get to hear my beloved fweem as much with that noise.
> Is it a sign that the alternator is getting ready to malfunction, that it is
> just "dumping" excess power at idle, that it is lugging... or what? The
> battery is good.
>
> TIA

Alternator normally doesn't make any noise. Possible bad bearing
(in the Alt)?
The noise could also be associated with the fan. Rubbing? Debris in
the blades?

If it *is* a bearing going bad, that could leave you stranded
somewhere when it seizes up...

Speedy Jim
http://www.nls.net/mp/volks/

On 12/7/2004 7:15 PM Speedy Jim stood on a soap-box and preached to the
unwashed masses:


> Alternator normally doesn't make any noise. Possible bad bearing
> (in the Alt)?
> The noise could also be associated with the fan. Rubbing? Debris in
> the blades?
>
> If it *is* a bearing going bad, that could leave you stranded
> somewhere when it seizes up...

Which brings up another subject. I have been reading, here and there,
hither and yon, tales of woe about poorly-built replacement alternators.
Rebuilt and new which break moments to weeks after installation. Is
there a known good vendor or way to identify a good-quality alternator?

--
Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westphalia: "Mellow Yellow (The Electrical Banana)"
KG6RCR
------------------------------------
Today's Deep Thought:

668: The Neighbor of the Beast.
------------------------------------

Hal wrote:

> " At idle it makes a racket
> that sounds sort of like a bunch of crickets. It dies down when I rev
> the
> engine a bit."
>
> A quick way to check the belt is to spray it with a bit of carb or
> brake cleaner while the engine is running. If the squeak goes away then
> it means the belt is slipping.

<SNIP>

Doh!
That's exactly the noise the belt makes!

Speedy Jim
http://www.nls.net/mp/volks/

>Which brings up another subject. I have been reading, here and there,
>hither and yon, tales of woe about poorly-built replacement alternators.
>Rebuilt and new which break moments to weeks after installation. Is
>there a known good vendor or way to identify a good-quality alternator?

The best rebuilder is the person who will be using it in their car.
They tend to care more. Study "how to" and do it using the same
approach you've been using on rebuilding your alternator/generator.

Typically all the parts will be available for repair/rebuild. The
hardest thing for most folks is cleaning up the slip ring area of an
alternator, and the armature contact surfaces on generators.

If you know what a growler is, then you can probably do a fine job of
rebuilding your own stuff.

Bearings are the simple part. But the most normally done poorly.
I had an instructor in Aviation school that taught me a bit about
"setting" a bearing properly. It requires a bench setup, but could be
made fairly simply by getting a pully and belt and mounting the pulley
to a bench grinder motor or the like. Just running it up to a decent
speed and "setting" the bearing takes a few seconds, but can be the
difference in a couple of hours of good service, and a decade of good
service.

If you havea way to run your piece up on the bench , just tapping the
housing around the bearing will true it up as it runs. makes a huge
difference to durability of the bearing/s. Us ea small ball peen
hammer for the tapping, and just work your way around each bearing for
about fifteen seconds or so total time each bearing..............

I know it sounds too easy, but It works. I have only had two that I
put bearings in and both outlasted the vehicles I did them
for...........by years. Yeah, that's not many repairs like that, but
one of them was in a bug generator. good results are worth sharing I'd
say.

your mileage may vary



Remove "YOURPANTIES" to reply

MUADIB®

http://www.angelfire.com/retro/sster...IN%20PAGE.html

one small step for man,.....
One giant leap for attorneys.

Find somebody you trust who does alternators. In my experience, these places are gross dirty as hell places. For
instance, last spring my Citroen 2CVs alt quit charging. OEM replacements are $150, new brushes are $15 plus shipping. I
went to a local alternator guy and he found some Mitsubishi brushes that would fit and sent me on my way for $15. I
didn't have to locate parts, nor did I have to put them in. That is value to me.
"Mike Rocket J. Squirrel Elliott" et> wrote in message
...
> On 12/7/2004 7:15 PM Speedy Jim stood on a soap-box and preached to the
> unwashed masses:
>
>
> > Alternator normally doesn't make any noise. Possible bad bearing
> > (in the Alt)?
> > The noise could also be associated with the fan. Rubbing? Debris in
> > the blades?
> >
> > If it *is* a bearing going bad, that could leave you stranded
> > somewhere when it seizes up...
>
> Which brings up another subject. I have been reading, here and there,
> hither and yon, tales of woe about poorly-built replacement alternators.
> Rebuilt and new which break moments to weeks after installation. Is
> there a known good vendor or way to identify a good-quality alternator?
>
> --
> Mike "Rocket J Squirrel" Elliott
> 71 Type 2: the Wonderbus
> 84 Westphalia: "Mellow Yellow (The Electrical Banana)"
> KG6RCR
> ------------------------------------
> Today's Deep Thought:
>
> 668: The Neighbor of the Beast.
> ------------------------------------

On 2004-12-09, Ben Boyle > wrote:

> I went to a local alternator guy and he found some Mitsubishi brushes
> that would fit and sent me on my way for $15. I didn't have to locate
> parts, nor did I have to put them in. That is value to me.


Pardon the thread hijack, but I got a question about this. A ways back
I was given an alternator that was missing it's brushes (the entire
fitting that is) but had never been used in a vehicle. Not a bosch
rebuild either, was a brand new unit. Since free and new is a damn
good price, I didn't ask questions.

At any rate, I've made some spotted efforts in the past to get just
the brushes so I could have a complete unit on hand as spare, with no
luck. I dug up the plastic piece at one point so I'm almost there.

My question is if there is some "standard" to brushes that I could use
to find replacements. Can I use anything that fits, if I find it?

Is there some readily available substitute that people commonly use?

Every business I've asked has basically told me to just buy a new
alternator, which kind of misses the point.

Apparently if it fits you are golden. Have you tried alternator rebuild shop? Like I say, I had a Citroen alternator
that the dude had never seen in his life and in a half hour he found some Mitsubishi brushes that fit, and had it
working again.
"Seth Graham" > wrote in message ...
> On 2004-12-09, Ben Boyle > wrote:
>
> > I went to a local alternator guy and he found some Mitsubishi brushes
> > that would fit and sent me on my way for $15. I didn't have to locate
> > parts, nor did I have to put them in. That is value to me.
>
>
> Pardon the thread hijack, but I got a question about this. A ways back
> I was given an alternator that was missing it's brushes (the entire
> fitting that is) but had never been used in a vehicle. Not a bosch
> rebuild either, was a brand new unit. Since free and new is a damn
> good price, I didn't ask questions.
>
> At any rate, I've made some spotted efforts in the past to get just
> the brushes so I could have a complete unit on hand as spare, with no
> luck. I dug up the plastic piece at one point so I'm almost there.
>
> My question is if there is some "standard" to brushes that I could use
> to find replacements. Can I use anything that fits, if I find it?
>
> Is there some readily available substitute that people commonly use?
>
> Every business I've asked has basically told me to just buy a new
> alternator, which kind of misses the point.
>

Don't they have alt brushes on Aircooled.net or something? They do have
generator brushes.

I have checked and it isn't the fan shroud rubbing.
It isn't a belt making noise... although my "custom oil misting" feature is
back even though I made sure the gen/alt stand, distributor, and fuel pump
seals were in ship shape. Maybe the case breather hose is too stretched and
is gunked up with sludge. But I digress.

The noise is definitely coming FROM the alternator. Another way to describe
the noise is a rhythmic version of the sound nails would make in a coffee
can when you shake it. Sort of a metalic cricket noise.... constant unless
revving.

I am hoping that it is not dying because the receipt for the alternator is
one of a very very very small handfull of receipts I don't have from ALL
purchases over the past few years (I keep EVERY receipt).

--
KWW
'65 Beetle (Jenny the IOC)
'64 Beetle (TBD the Blue Wave)
"Seth Graham" > wrote in message
...
> On 2004-12-09, Ben Boyle > wrote:
>
>> I went to a local alternator guy and he found some Mitsubishi brushes
>> that would fit and sent me on my way for $15. I didn't have to locate
>> parts, nor did I have to put them in. That is value to me.
>
>
> Pardon the thread hijack, but I got a question about this. A ways back
> I was given an alternator that was missing it's brushes (the entire
> fitting that is) but had never been used in a vehicle. Not a bosch
> rebuild either, was a brand new unit. Since free and new is a damn
> good price, I didn't ask questions.
>
> At any rate, I've made some spotted efforts in the past to get just
> the brushes so I could have a complete unit on hand as spare, with no
> luck. I dug up the plastic piece at one point so I'm almost there.
>
> My question is if there is some "standard" to brushes that I could use
> to find replacements. Can I use anything that fits, if I find it?
>
> Is there some readily available substitute that people commonly use?
>
> Every business I've asked has basically told me to just buy a new
> alternator, which kind of misses the point.
>