REFLECTOR: N173VS RPM

Tue Feb 21 20:25:44 CST 2012

I headed out to the hangar tonight and think I may have found the problem.
 I checked the fuel lines for blockages all the way from the boost pump to
the divider and flow was fine.  I took all the injectors out and put them
in cups, turned the fuel pump on and mixture to full rich, they all spurted
nicely except one - the silver solder joint that joins the stainless steel
fuel line to the nipple that connects to the injector was bad and it was
leaking out that joint and not going thru the injector.  I brought it home,
cleaned it up and re-soldered it with new silver solder.  I'll give it a
whirl tomorrow and see if it fixed the problem.

I moved the fuel pressure tap to the fuel divider.  My fuel and oil
pressure sensors are mounted on a manifold on the firewall with copper
tubes running to the pressure tap points.  When I turned on the fuel pump,
I did see a pressure reading from the fuel pressure sensor, but because the
one injector was leaking, it was not building up much pressure.  We'll see
when I put the repaired injector line back in...

Geoff

On Tue, Feb 21, 2012 at 4:29 PM, Andy Millin <amillin at sbcglobal.net> wrote:

> Big smiles here…****
>
> ** **
>
> You’re not supposed to be focusing in on the cylinder temps now.  You’re
> supposed to be grinning and driving that thing around the airport.  You’ve
> earned it.****
>
> ** **
>
> The temps will tell you if all the sparklers and squirt guns are working.
> If you have a cold cylinder, then you’ll need to address it.****
>
> ** **
>
> If it is stumbling at high RPM then I would look to the mixture.****
>
> ** **
>
> You have a Lycoming IO-360 200 HP; or it looks like you do.****
>
> ** **
>
> The servo will control the metered fuel to the cylinders.  Since that
> would have to be adjusted at a shop, I would take care of the simple stuff
> first and see how many problems are left.****
>
> ** **
>
> This is just another step along the building path.  Keep working the
> problem and you’ll get it.****
>
> ** **
>
> Andy****
>
> ** **
>
> ==========================****
>
> Andy Millin****
>
> amillin at sbcglobal.net****
>
> ** **
>
> *From:* reflector-bounces at tvbf.org [mailto:reflector-bounces at tvbf.org] *On
> Behalf Of *Geoff Gerhardt
> *Sent:* Tuesday, February 21, 2012 12:01 PM
>
> *To:* Velocity Aircraft Owners and Builders list
> *Subject:* Re: REFLECTOR: N173VS RPM****
>
> ** **
>
> Andy,****
>
> ** **
>
> Thanks for all the good suggestions.  I'm typically only able to get out
> to the hangar on weekends, but its supposed to be in the 50's here this
> week, so I'll probably sneak out there a couple evenings this week to check
> on a few of the things you've mentioned.****
>
> ** **
>
> While I have the great Dynon Skyview system that tracks all the engine
> parameters, I'm kicking myself now for not taking note of more
> temperatures/pressures.  I was so excited to be taxiing around, I was
> looking outside to be sure I didn't hit something more than looking at the
> panel.  Even when I was just standing still doing the static runup, I was
> listening to the engine and adjusting the mixture and things and not paying
> enough attention to all the sensor readings other than making sure the oil
> temp/press was coming up.  I will probably connect my laptop to the skyview
> for the next start and log everything so I can look back on it.****
>
> ** **
>
> Anyway, there's a number of issues that I need to resolve before I try
> again.  ****
>
>    - I need to figure out why my fuel pressure reading is so low.  I
>    checked the sensor, and it responds to pressure changes, is getting fuel
>    and has good grounding.   Oil pressure sensor mounted beside it works fine
>    (indicating good ground to the block their both mounted on).  My feeling is
>    that the low pressure is real, but I'm going to connect an analog dial
>    gauge and check it.  ****
>    - There's still a problem with my LightSpeed EI.  The disable switch
>    does not work.  Only when I turn power off to the EI unit does it stop
>    working.  Also, the RPM output from the LightSpeed unit is not
>    working/being seen by the Dynon Skyview.  I have it connected to the
>    low-voltage Tach input of the Dynon EMS, but when I switch off the Mag, RPM
>    drops to zero when only running on EI (the Dynon allows two RPM inputs and
>    should switch intelligently b/w them).  The EI unit seems to be functioning
>    well and providing good spark aside from these issues, tho.****
>
> Once I resolve these issues, I'll give it another go...****
>
>
> One other thing - when I go to full throttle, the engine starts to sputter
> and I need to lean it out (~ half way) to achieve maximum power.  Is that
> consistent with a fuel flow problem?****
>
> ** **
>
> Thanks again for the help.****
>
> ** **
>
> Geoff****
>
> On Tue, Feb 21, 2012 at 9:57 AM, Andy Millin <amillin at sbcglobal.net>
> wrote:****
>
> Geoff,****
>
>  ****
>
> Congrats on the taxi.  It looked great.****
>
>  ****
>
> If you are looking for some help on the low static RPM…****
>
>  ****
>
> You said you were getting low fuel pressure readings.  What fuel flow do
> you get?****
>
>  ****
>
> It looks like you have a Lightspeed EI.  Are you running 1 and 1?  What is
> the “mag” check like.  Are both systems firing.****
>
>  ****
>
> Do you have an engine monitor?  What are the EGTs and CHTs looking like
> when running on either ignition system.****
>
>  ****
>
> How much time have you spent on leaning the engine.  When I started my
> engine on the plane, it was running very rich.  The Catto prop is very
> light and will not be much of a flywheel.  So, you’re keeping the RPM up
> just to keep it running.****
>
>  ****
>
> I have a Prince prop.  It was a challenge to get it to idle below 800
> RPM.  It wasn’t until Terry Brokaw helped me get the idle settings right
> that I could get it to 600 RPM.****
>
>  ****
>
> Where is your fuel pressure sensor located?****
>
>  ****
>
> If you are running both the mechanical and electric fuel pumps, there is a
> pretty good chance you can make the pressure you need.  The pressure to the
> spider will be controlled by the Servo.****
>
>  ****
>
> If the EGTs and CHTs are in the same ball park for all cylinders, then the
> blockage (if any) would be before the spider.  Fuel Filter, Fuel Shutoff
> Valve, lines, etc. ****
>
>  ****
>
> It is also possible your prop is over pitched.  Craig has been known to do
> that.****
>
>  ****
>
> Andy****
>
>  ****
>
> ==========================****
>
> Andy Millin****
>
> amillin at sbcglobal.net****
>
>  ****
>
>
> _______________________________________________
> To change your email address, visit
> http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html***
> *
>
> ** **
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.tvbf.org/mailman/private/reflector/attachments/20120221/ada9e563/attachment.htm>