I currently have a separate ground from each
of the batteries to a Nuckolls “forest of tabs” ground point.
Everything inside the cockpit grounds here. Also the fuel pumps and
injectors ground here. The coils ground on the center iron. There are
separate grounds from each battery to the PSRU plate on each side of the
starter. I have considered bringing two separate grounds from the center
iron to the batteries just in case there is resistance getting from the center
iron to the PSRU plate.
I am also taking all my grounds apart to
check for corrosion or anything that seems that it might not be properly
bonded.
I am doing this for two reasons. One,
I am still getting that occasional “hiccup” that is violent enough
to shake the plane when it happens. It is bad enough that I am concerned
that it might be bad for the pin in the PSRU. I am also wondering if it
could be the PSRU that has sheared the pin and is slipping? Someone on
here had that happen and I would really appreciate a description of what that
sounded and felt like and also how I could make certain that is not the
problem. No, I don’t want to dismantle the PSRU to check it unless
that seems to be the only way to check it.
Also, Tracy, how are you progressing on getting the
upgrade for the EC-2 that might fix this hiccup if that is what it is? I think
you had it done for the EC-3 and were working on the EC-2 implementation??
The second reason for going thru the
grounds is that I am having an intermittent problem with my GTX327 transponder,
MFD150 moving map, and TruTrak autopilot shutting down. This seems to
happen more often when I key the mike on my GNS430W radio, but keying the mike
is not required. It sometimes happens just out of the blue. Also most
of the time, only the transponder shuts off. Only sometimes does the
moving map and autopilot join in the fun.
Everybody tells me that it sounds like a ground
issue, hence I am going thru the ground system.
I welcome all opinions and input!
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Tracy
Sent: Saturday, December 08, 2012
10:56 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Aeroquip
hose
Tying the engine parts
together should not be necessary but you still need a separate ground from
battery to airframe ground (if metal) and your avionics ground
point. Also separate feeds from +12 battery to starter/alternator
and avionics. You can Use the starter/alternator feed for coils,
injectors & fuel pumps to keep noise down on the avionics bus.
Tracy
On Sat, Dec 8, 2012 at 12:23 AM, Bill
Bradburry <bbradburry@bellsouth.net> wrote:
Several months ago, after a discussion with Tracy, I ran grounding straps from each
battery to the PSRU plate on both sides of the starter mount. I had
previously had the grounding strap running between the center iron and the
“forest of tabs” grounding block on the firewall. Tracy suggested I move it
so the starter amps would not get into the grounding block.
Now I have the igniters grounded on the center iron and I am
considering running a ground strap from the center iron to the batteries or
trying to tie each section of the engine “sandwich” together by
running a wire between them. This would to be certain that the ground is
good on the igniters.
Any opinions on this??
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]
On Behalf Of Andrew Martin
Sent: Friday, December 07, 2012
8:29 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Aeroquip
hose
Bill
As Mark says + make sure you have a ground cable/strap connected battery direct
to your starter. Do not expect starter to ground through your engine without
problems.
I remember Tracy
posting on this issue years ago just a bit hard to find in the archives now.
Andrew
On Sat, Dec 8,
2012 at 7:26 AM, Mark Steitle <msteitle@gmail.com> wrote:
Bill,
You may want to
check your engine ground. Starter current may be causing this.
On Fri, Dec 7,
2012 at 5:12 PM, Bill Bradburry <bbradburry@bellsouth.net>
wrote:
I am working on
cleaning up my ground system and I noticed that I have
several, 3 or 4, places on my SS braided fuel hose that appears to be burnt
like it had an electrical spark exit from it. I have not found anything
in
the vicinity of these places that look like where the spark? would have
jumped??
Has anyone seen something like this and what should I do about it? Do I
have a ground problem in the engine compartment or is this maybe static?
The hoses are covered by SS and are connected on one end to a filter that
has a ground strap on it and on the other end to the fuel rail which is
grounded to the engine.
Bill B
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