<VV> Clutch?> Astro 1 engine fans

[Mel Francis]

I don't think so, Chuck.
Here's a view of the shaft and the drive went directly from the crank to the 
bevel gear
that drove the fan: http://www.pbase.com/917carl/image/21848755
The rest of this long shaft was used to drive the alternator.
There might have been a clutch inside the larger diameter fan hub, bu it 
hasn't shown up in any drawings:
http://www.pbase.com/917carl/image/21873581

Mel

----- Original Message ----- 
From: "BBRT" <chsadek at comcast.net>
To: "Mel Francis" <mfrancis at wi.rr.com>; "Jim Simpson" <simpsonj at verizon.net>
Cc: <virtualvairs at corvair.org>; <fastvair at yahoogroups.com>
Sent: Tuesday, March 19, 2013 9:57 AM
Subject: Clutch?> Astro 1 engine fans


> Does anyone know if Porch used a type of sprag clutch or other for 
> override on their mechanically driven horizontal 935 fans? Keep in mind, 
> those engines were expected to be torn down after each race, so any gear 
> wear would be addressed.
>
> Chuck S
> BBRT
> ----- Original Message ----- 
> From: "Mel Francis" <mfrancis at wi.rr.com>
>
>
>> For those who can read mechanical blueprints, I've posted the top view
>> drawing of the Astro engine.
>> http://www.flickr.com/photos/mel_francis/8571083561/in/photostream
>> As you can see, there are three disc-type fans on the main shaft, with 
>> vanes
>> on both sides of the disc.
>> These fit into a lower casting that matches the vanes closely and is 
>> closed
>> off by a top cover,
>> or perhaps three separate fan covers that complete the pressure rings.
>>
>> Perhaps the main reason that nobody has replicated this system, even GM, 
>> is
>> complexity and the
>> resulting cost. There is also a fair amount of rotating mass, more than
>> double that of the stock mag fan and
>> that would certainly become a problem in any higher performance 
>> application.
>>
>> Mel
>>
>>
>> ----- Original Message ----- 
>> From: "Jim Simpson" <simpsonj at verizon.net>
>>
>>
>>> Now that I've been given directions on how to actually search the VV
>>> archives,
>>> I'm emboldened to ask this question regarding Corvair engine fans:  Has
>>> anyone attempted to replicate the Astro 1 overhead cam engine cooling
>>> system?  (I didn't see any obvious references to attempts to replicate
>>> this
>>> system.)
>>>
>>> The Astro 1 engine was a major redesign to incorporate a number of major
>>> improvements to the Corvair engine.  The major one was the SOHC design,
>>> but
>>> the cooling system was also radically different in that it used three
>>> blowers
>>> (squirrel cage?) on a single horizontal shaft.  The fan routing was
>>> simplified to eliminate the 90 degree bends and looks much more like a
>>> conventional layout.
>>>
>>> I've seen some of the Porsche fan adaptions to the Corvair engine so
>>> itseem pretty obvious that the fan belt
>>> routing could be done on a more or less stock engine, but has anyone
>>> actually investigated the fans themselves?
>>>
>>> Jim Simpson
>>> Group Corvair
>