James P. Rice
ricebugg at comcast.net
Tue Nov 14 17:26:30 EST 2017
Hugo: I'm retired from Caterpillar, which uses a lot of hydraulics on all
the products. Back in the mid to late 1980's I had the same idea about
driving the Corvair fan hydraulically. So, since I had access to the
Similar Parts books, I went looking at what Cat had/use in the way of
Hydraulic pumps. They had several modest size pumps, but size and weight
were the issue. And you still have to have a belt to drive the pump, which
would still be subject to the shock of rpm changes on downshifts. Without
the two bends in the belt drive, it might work, buy the size and weight is
still an issue. The routing of the hoses from pump to the top of the fan is
also an issue.
Another idea is to use a hi psi/hi flow oil pump and figure out how to bleed
off some of the oil flow to spray against or into a pump drive under the top
engine cover. A turbine impeller mated to the rotating vertical shaft with
the fan pulley bolted to the top of the shaft. Or use a second oil pump
similar to a dry sump set up. (Bill Thomas ran a dry sump on his Corvair
race car at one point back in the early 60's, so a second external pump is
doable) and route the oil under/into the pump or some other drive set up
inside the top engine cover, Draining the oil back into the crankcase may
be a issue. Or getting it back to the second external pump. Maybe some
internal duct work to do to get the oil so it doesn't hit the crankshaft or
rods as the whirl away? Not all that hard to conceptualize, maybe difficult
to impossible to engineer...! VBG!!!
Don't stay awake thinking about it. But imagine the looks on the faces of
bystanders as the fan turns without a visible drive system!
Vertical fan is thus far the best way to solve the problem if you are doing
serious high rpm downshifts like the racers do.
Isn't it fun to try and figure out how to solve the problems we create when
we use our Corvairs for anything other than their intended use as grocery
getters or 2nd car to drive to work in?!
Date: Tue, 14 Nov 2017 09:07:04 -0000
From: "Hugo Miller" <Hugo at aruncoaches.co.uk>
To: "kevin nash" <wrokit at hotmail.com>, <jimster1 at earthlink.net>,
<virtualvairs at corvair.org>
Subject: Re: <VV> My new experimental fan
I operate a small coach company in the UK, and my coaches have the
radiator on the left side at the back, away from the engine, with a neat
hydraulic fan drive. Very simple and works really well, with the added
advantage that it can be thermostatically controlled. I've often wondered
whether this system could be applied to the Corvair?
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