When several parameters are all varying and cannot be attributed to the
engine the most likely problem is some form of earth fault.
As an aside - from a sender point of view the most unreliable sender
tends to be the oil pressure sender which is not tolerant to vibration.
Many of us have found that if the oil pressure sender is mounted
remotely from the engine its life is greatly improved.
Nigel Charles
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Martin Tuck
Sent: 23 January 2009 03:52
Subject: Europa-List: Grand Rapids EIS-2004 Question
Hi Folks,
I have had my Grand Rapids EIS (Model 4000) installed for a year now and
it really performs well - ah, until recently. While I was taking a
cursory look during one flight I noticed my oil pressure was down in the
20 psi range and fluctuating. Then it went back up to the normal 40 psi
or so. Then down it went again. Meanwhile the other indications were
fluctuating, EGTs were varying 10-20 degrees up and down, the oil
temperature was increasing and decreasing up and down in line with the
oil pressure fluctuations. Then the warning lamp triggered and the error
appeared to be low voltage at 6 volts, then 3 then back up to around a
more normal 13-14 volts. As I continued I would see indications from
normal to warnings of low oil pressure, high oil temperature, low
voltage, etc. then back to normal. Occasionally the indications were as
if the unit had shut off then immediately restarted taking me back to
the default display page. I decided the unit had probably developed a
fault so I continued back to base - a long 10 minutes away.
I called Grand Rapids support and they doubted the unit was at fault but
more likely that a sender was on the fritz. What surprised me is that
according to them, one dodgy sender affects all the readings and you
have to basically disconnect each sender until the problem disappears.
Any one else had any problems like this?
I have to say, I would rather have a system which has independent
displays such that one sender does not affect the others, any
suggestions?
Over winter I have pulled the panel and checked all the wiring which
appears normal, no shorts, all the spare wires on the EIS have been
capped off with heatshrink, and I flew it again today with the same
sporadic indications occurring in the first 5-10 minutes and continuing
throughout most - but not all, the flight. I guess I will try to track
down the dodgy sender.
Thoughts anyone?
Regards,
Martin Tuck
Europa N152MT
Wichita, Kansas
Checked by AVG - http://www.avg.com
1/22/2009 7:08 AM
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