REFLECTOR: Franklin Fuel Pump Issues

[Jay Yu]

Hi Mike and All Franklin Drivers,

I know that I am late in the game on this. I just installed my new fuel pump
that's working well. But, like Mike's original configuration, my SigmaTek
vacuum pump used to be on fuel pump drive and now has been moved to rear
pilot side. When I started the engine, I didn't get any vacuum at idle
speed. I only got about 3" HG when the engine was running 1800RPM. The GREEN
arc is about 4.5" to 5.5" HG. How much vacuum can you get and at what RPM
(Mike?) What's the lowest vacuum we need for safe flight?

My vacuum pump did have about 80 hours in original configuration. In that
configuration, the vacuum was in GREEN easily (may be a little over 1000
RPM). With this new installation, I adjusted the vacuum regulator (both ways
to extreme) but still cann't get more than 3" at about 1800 RPM.

Any and all hints will be greatly appreciated.

Jay Yu
N86YU
Velocity RGE
Franklin/MT



-----Original Message-----
From: owner-reflector@dax.awpi.com
[mailto:owner-reflector@dax.awpi.com]On Behalf Of mike deeter
Sent: Friday, November 01, 2002 12:17 PM
To: reflector@tvbf.org
Subject: Re: REFLECTOR: Franklin Fuel Pump Issues


Franklin drivers:

OK , so now I'm answering my own emails.

I just got off the phone w/ my engine builder, Pete
Askeland at Franklin Aircraft Engines, Inc. (FAEI) in
Colorado.

Referring to the problems I've outlined in my email
below.  If you have a bidirectional vacuum pump you
will have no problem; just switch the input and output
lines.

If you don't have a bidirectional pump you will
obviously have to get a new vacuum pump.

As for the speed of the accessory pad:  FAEI has the
STC for Cessnas w/ Franklins and they run their vacuum
pumps off the accessory pad in question, i.e. no
problem running vacuum off the pad on the pilot side
near the prop.

Sorry to get us all excited.

Mike

--- mike deeter <iguanamagic@yahoo.com> wrote:
> Franklin drivers:
>
> Well, I got my fuel pump installed and fuel lines
> redone.  I only needed to hoist the engine for
> taking
> the old one off.  I was able to reinstall the new
> one
> w/ the engine bolted tightly to the firewall.
>
> I installed the vacuum pump on the pilot side accy
> pad
> near the prop.  Unfortunately, this may not work as
> well as PZL intended.  Larry Coen pointed out the
> accy
> pads near the prop turn 0.847 times crank CW while
> the
> accy pad on the rear of the engine (fuel pump mount)
> turns 1.65 times crank CCW.
>
> This could be a problems (ahem, issue).
>
> The vacuum pump will now turn more slowly and
> opposite
> the way it previously turned (it previously was on
> the
> fuel pump drive).  I called SigmaTek about this and
> they said, though the pump is bi-directional, the
> direction change is significant because it gets a
> wear
> pattern after awhile and changing could shorten the
> life.  I only have 12 hours on mine so they said it
> should be OK.  The other problem is they said their
> pump needs about 1500 RPM to get good vacuum (gauge
> in
> the green) so at 0.847:1 I'd need around 1800 crank
> RPM to get good vacuum.  Hmmm.
>
> The SigmaTek guy did say that other pumps on the
> market only need 1200 RPM to get up to speed so only
> would need around 1400 crank RPM to get good vacuum.
>
> Still not the best situation.
>
> I hope to get some comments from the Franklin guys
> to
> see what ideas are out there for solving this
> problem.
>  Can't go running around w/o vacuum.
>
> Sorry to be the bearer of bad tidings.
>
> Mike Deeter
> N2011P Franklin RG E
>
>
>
> =====
> *******************************************
> Mike Deeter
> N2011 Test Pilot
> iguanamagic@yahoo.com
> http://iguanamagic.siegesmund.org
> *******************************************
>
> __________________________________________________
> Do you Yahoo!?
> HotJobs - Search new jobs daily now
> http://hotjobs.yahoo.com/
> -
> To change your email address, send an email to
> majordomo@tvbf.org with the body:
> subscribe reflector <new email address>
> unsubscribe reflector <old email address>
> Visit the gallery!  tvbf:jamaicangoose


=====
*******************************************
Mike Deeter
N2011 Test Pilot
iguanamagic@yahoo.com
http://iguanamagic.siegesmund.org
*******************************************

__________________________________________________
Do you Yahoo!?
HotJobs - Search new jobs daily now
http://hotjobs.yahoo.com/
-
To change your email address, send an email to majordomo@tvbf.org with the
body:
subscribe reflector <new email address>
unsubscribe reflector <old email address>
Visit the gallery!  tvbf:jamaicangoose