[NoVa-Corvairs] RedBrier

[Curtis Shimp]

Al:

Yes, I used a heavier spring.  You can also stretch them or put shims
under them to make them stiffer.  For years I used the after market "high
volume" oil pumps.  As I understand it they do nothing for pressure but
do help push more volume through the system IF you have drilled out the
oil passages to accept the higher flow, which I did.  On a stock Corvair
engine they really don't do anything but take more horse power to turn. 
Additionally you need to notch the steel plate under the motor mount for
clearance as the pump housing is longer (deeper?).  Another key to
getting good oil pressure is to get the correct clearance between the end
of the pump gears and the pump housing.

Curt

On Tue, 22 May 2007 20:49:38 -0400 "ALBERT BIRKS" <foxchase123 at msn.com>
writes:
> Curt:  What did you do to tweak your oil pumping system to get 40 
> psi?
> Did you increase the spring pressure of the control valve or did you
> make a physical change in the pump itself?
> 
> Re current (Clark) fuel pumps, I purchased one in '05 from Clarks 
> and
> replaced my old pump before I drove to the Portland OR, national 
> meet.
> I drove from Kennewick WA, to Portland and back on the interstate, 
> about  
> 400 miles at outside temperatures of 100 degrees. The pump worked  
> faultlessly all the way.  I haven't started it since then, so can't 
> vouch for
> long life.  We understand that the NAPA pumps are not reliable, but 
> that
> may be a rumor too.
> 
> Al B
> 
> ----- Original Message -----
> From: Curtis Shimp
> Sent: Tuesday, May 22, 2007 7:12 PM
> To: novacc-list at corvair.org
> Cc: novacc-list at corvair.org
> Subject: Re: [NoVa-Corvairs] RedBrier
> 
> Greg:
> 
> Regarding the life of the fuel pump 15,000 is far short of the 
> original
> design criteria.  However, as you know they are all after market 
> pumps
> now and who knows how long they are expected to last.  I have no 
> first
> hand experience to give you as I changed to an electric pump 20 
> years ago
> (it's still working).
> 
> There have been numerous articles about premature failures with 
> after
> market pumps and from this two camps have emerged.  One, lead by Lon
> Walls, says that the mechanical pumps now being ordered by he and 
> Clark's
> have resolved all the past issues.  The other says don't take a 
> chance,
> get an electric pump.  The problem I have with the first group is, 
> how
> can you tell by looking whether you have a "no problem" new pump or 
> not.  
> I guess you could order a new one and cross your fingers.
> 
> By the way if the pump fails it does not necessarily push gasoline 
> into
> the crankcase.  There is a form of failure where the gasoline is 
> shot out
> of the vent hole on the top of the pump.  You know we have a local 
> expert
> on this subject, John Moody.
> 
> Regarding oil viscosity, use the lightest viscosity oil that 
> maintains
> good oil pressure.  In a Corvair that is about 30 lbs.  The rule of 
> thumb
> is 10 lbs. per 1,000 rpm but Chevy did not build Corvairs that way.  
> If
> your doing the freeway to the convention at 65 mph and only getting 
> 20
> lbs., that is too low and you will need to put a heavier oil in the
> engine.  I have "tweaked" my oil pump to put out 40 lbs.
> 
> Curt
> _______________________________________________
> Novacc-list mailing list
> Novacc-list at corvair.org
> http://www.vv.corvair.org/mailman/listinfo/novacc-list