Date: Sun, 23 Sep 2012 09:50:36 -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.
In-Reply-To: <BAY152-ds8DEF47C479B6ADC11E20BA09F0@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
"You should be able to use a wrench on the alternator pulley and turn
the engine without the belt slipping."
Ah, then it's a bit loose.
"You can get a belt tension gauge."
Looks like a $100 item, not in my budget I guess.
"You can also upgrade the top bracket-bolt set with the 90+ setup which
has a toothed drive to tighten the belt."
Who sells such things?
Also, Dennis wrote, "Some of the real early 1.9s had a 65 amp alternator
and a single groove crank pulley. The alternator was upped for the at
port AC installations and the three groove pulley for the even later
power steering."
Um, this engine has a crank pulley with three separate grooves, each
smaller than the one in front of it. Is that what is being described here?
--
Jack "Rocket j Squirrel" Elliott
1984 Westfalia, auto trans,
Bend, Ore.
On 09/23/2012 09:24 AM, Dennis Haynes wrote:
> You should be able to use a wrench on the alternator pulley and turn the
> engine without the belt slipping. You can get a belt tension gauge. You can
> also upgrade the top bracket-bolt set with the 90+ setup which has a toothed
> drive to tighten the belt. Torque wrench 6 ft lbs.
>
> Dennis
>
> -----Original Message-----
> From: Rocket J Squirrel [mailto:camping.elliott@gmail.com]
> Sent: Sunday, September 23, 2012 12:15 PM
> To: Dennis Haynes
> Cc: vanagon@GERRY.VANAGON.COM
> Subject: Re: Alternator continuous-duty rating?-V-belt drive rating.
>
> "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
>
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