Date:         Sun, 23 Sep 2012 09:14:32 -0700
Reply-To:     Rocket J Squirrel <camping.elliott@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Rocket J Squirrel <camping.elliott@GMAIL.COM>
Subject:      Re: Alternator continuous-duty rating?-V-belt drive rating.
Comments: To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
In-Reply-To:  <BAY152-ds76FFF80C820CCC5B59997A09F0@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

"This is why belt tension is so important [...]"

Lame-o confession: I never know when my belt tension is right. The
push-to-check-deflection thing is so subjective to me that I just don't
trust my results. The engine squeals sometimes when I start it. Reckon
it's the belt.

--
Jack "Rocket j Squirrel" Elliott
1984 Westfalia, auto trans,
Bend, Ore.

On 09/23/2012 07:51 AM, Dennis Haynes wrote:
> The water boxer engine cannot reliably drive a larger alternator due to the
> drive belt set. Most belt drives are designed around the belt having a 180
> degree wrap around the drive and driven pulleys. On the waterboxer the belt
> only skims around the drive pulley limiting the amount of friction available
> to drive the load. This is why belt tension is so important and from the
> factory a special high tensile strength belt was used.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> David Beierl
> Sent: Saturday, September 22, 2012 11:13 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Alternator continuous-duty rating?
>
> At 07:41 PM 9/22/2012, Rocket J Squirrel wrote:
>> I don't think the 90-amp rating is a continuous rating. It's probably
>> peak rating, or one-hour rating or something, but not continuous. I'm
>
> Just some context - with 90 amps at 13.6 volts, assuming 85% efficiency the
> alternator will be sucking down about two horsepower from the belt and
> dissipating about 225 watts as heat.
>
> I don't know how much the water pump uses, but you're definitely pushing the
> edges of what most marine folks recommend driving with one automotive vee
> belt, especially the 3L size that we use.
>
> There's a little calculator at
> http://www.gizmology.net/pulleysbelts.htm for required tension and such.
> Only set up for two-sheave systems, but it's something.
>
> I took squint around www.gates.com for hp ratings and got nowhere useful.
> Stopped short of asking an engineer, which they provide for on the site.
>
> Yrs,
> d