Hi All,
I have been getting a lot of calls at the US office lately requesting guidance
for installing engine instruments.
There are some neat new products available, like the EIS mentioned below. The
EIS is a great way to monitor a large number of engine parameters previously
impossible
to do with analog gages.
The EIS, however, it not as easy to read as an analog instrument. Our engines
are not cheap, and our butts are worth even more, so I strongly recommend that
for the most important engine parameters, easy to read analog gages be installed
in an area easy for the pilot to spot. Examples are the Tachometer, hottest
CHT, Oil Pressure, and Manifold Pressure for constant speed props. It is much
easier to spot a fluxing, or dropping oil pressure needle than to spot, or
page to the number on an EIS. Once the red light comes on there will not be
as much time left to find a place to land.
For a 914 you also need to have something that tells you the difference between
fuel pressure & boost pressure in the same units - ex, both in inches of
mercury,
or pounds per square inch. I am working with an instrument manufacturer
to make a single gage that does this to save space, but don't have one yet.
Rotax
recommends a twin MP gage for this, but they only come in 3 1/4.
Another reason for installing engine instruments is noted below. If the monitor
fails, then there is no way to tell what the engine is doing.
Finally, these instruments are cheap, as little as $35 each.
Hope this answers some of your questions.
John Hurst
Europa Aircraft
Lakeland, FL
-----Original Message-----
From: Carl & Dot <carl_p@ntlworld.com>
Subject: Re: Europa-List: Faulty Oil Temp sensor
It turns out there is nothing wrong with the sensor although initial checks
with the ohm meter suggested this was the problem.
It seems to be much worse. and the problem is somewhere in the Grand Rapids
EIS unit. Not only is the oil temp wrong but most other readings are now
abnormal.
Guess well have to return it to Grand Rapids and see what they have to say.
Pity as the annual permit is due to expire in 10 days.
Carl pattinson
G-LABS (grounded for the time being)
----- Original Message -----
From: <n3eu@comcast.net>
Subject: Re: Europa-List: Faulty Oil Temp sensor
>
> Carl & Dot wrote:
> > ...
> > I think my preferred choice would be to mount the sender in the return
line
> > from the bottom of the crank casing (would need a metal block to screw
into)
> > where I assume it would be at its hottest. An easier fix might be to
bolt it
> > into the oil tank somewhere. This would be simpler, and there would be
less
> > vibration. Possibly a hole tapped into the centre of the oil tank drain
plug
> > would work.
>
> I believe Rotax is sensing cooled oil -- not the hot stuff in the return
line nor similar in the tank, and they set the redline temp premised upon
the effect of mounting in the engine block where they do. I would caution
against any mod which cannot verify the Rotax redline temp is still valid,
or proper testing to set a new value. So far we have one reported instance
of a complete failure only alleged due to vibration. A google search I did
turns up nothing else, nor is there a service bulletin. If vibration can
fail the sensor, then the temp instrument will go blooey, so then just
replace it. A significant cause of homebuilt accidents is this type of
experimentation, resulting in doing things in ways not seen on production
aircraft for presumably valid reason.
>
> Regards,
> Fred F.
>
>
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