Today's Message Index:
----------------------
1. 01:30 AM - Re: Ethanol in fuel. What about Brazil? (Brian Davies)
2. 07:48 AM - Two ignitions on Rotax (rparigoris)
3. 08:47 AM - Re: Two ignitions on Rotax (Robert Borger)
4. 08:49 AM - Re: Two ignitions on Rotax (Bud Yerly)
5. 11:48 AM - Re: Two ignitions on Rotax (Rowland Carson)
6. 11:54 AM - Start 914 on A, B or both? (rparigoris)
7. 12:01 PM - Re: Two ignitions on Rotax (rparigoris)
8. 04:00 PM - 914 Servo Problem -- broken copper wiper -- is there a fix? (PCahill)
9. 05:01 PM - Re: 914 Servo Problem -- broken copper wiper -- is there a fix? (rparigoris)
10. 05:21 PM - Re: Re: Two ignitions on Rotax (Bud Yerly)
11. 05:27 PM - Re: 914 Servo Problem -- broken copper wiper -- is there a fix? (PCahill)
12. 05:32 PM - Re: 914 Servo Problem -- broken copper wiper -- is there a fix? (Bud Yerly)
13. 06:32 PM - Re: 914 Servo Problem -- broken copper wiper -- is there a fix? (rparigoris)
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| Subject: | Ethanol in fuel. What about Brazil? |
Hi Steve,
The LAA is not saying you must not use fuel with any ethanol. You can use
Mogas to EN228. See LAA Technical Leaflet TL.2.26 Procedures for use of E5
Unleaded Mogas to EN228. Note that it talks about E5. The LAA has yet to
issue advice regarding E10.
The point I was trying to make was that if you are worried about this you d
o
not have to use Avgas. There other alternatives. Bud has provided good
advice on this although fuel specs in the UK ( and the way octane ratings
are quoted) is different.
Regards
Brian
From: owner-europa-list-server@matronics.com
<owner-europa-list-server@matronics.com> On Behalf Of Steve Ivell
Sent: 20 March 2021 01:53
Subject: Re: Europa-List: Ethanol in fuel. What about Brazil?
Hi Brian
The Rotax engine isn't the problem..... it's the engine ancillaries. So....
providing we use ethanol proof rubber components there shouldn't be too man
y
problems. And I have.
The LAA saying we mustn't use fuel with any ethanol in it is unfair as the
petrol stations don't even know if there is ethanol in their own fuel, and
the engine doesn't really care.....it still works fine.
UL91 isn't readily available locally to me so why should I have to waste
time and fuel flying to an airfield that has UK??
I'll be using mogas and taking appropriate precautions.
Kind Regards
Steve Ivell
_____
From: owner-europa-list-server@matronics.com
<mailto:owner-europa-list-server@matronics.com>
<owner-europa-list-server@matronics.com
<mailto:owner-europa-list-server@matronics.com> > on behalf of Brian Davies
<brian.davies44@gmail.com <mailto:brian.davies44@gmail.com> >
Sent: Friday, March 19, 2021 9:33:35 AM
<europa-list@matronics.com <mailto:europa-list@matronics.com> >
Subject: RE: Europa-List: Ethanol in fuel. What about Brazil?
Hi Steve,
I can assure you that the LAA are not living in the past on this subject.
When 5% Ethanol was introduced into Mogas the UK CAA effectively banned its
use. The LAA worked hard to get this reversed and eventually the CAA agree
d
that the LAA could determine which aircraft and/or engine types could use
Mogas with 5% Ethanol. Although the Rotax is cleared for fuel with some
Ethanol the aircraft fuel system may not be. Most of the problems we have
experienced have been related to fuel tanks and fuel pipes and poor
operating practices, such as leaving stale fuel in the system. The
introduction of 10% Ethanol will require a re-think. In the meantime, avoi
d
using it as long as there are good alternatives such as UL91 or premium
grade Mogas without Ethanol.
A question for you before you finish your aircraft- what specification fuel
lines have you installed? Are they Ethanol proof? The stuff Europa
originally supplied is resistant but not proof because we did not have
Ethanol in fuel when it was originally specified.
Regards
Brian Davies
From: owner-europa-list-server@matronics.com
<mailto:owner-europa-list-server@matronics.com>
<owner-europa-list-server@matronics.com
<mailto:owner-europa-list-server@matronics.com> > On Behalf Of Steve Ivell
Sent: 18 March 2021 22:49
Subject: Re: Europa-List: Ethanol in fuel. What about Brazil?
Hi Jonathan
The Rotax engine is fine with ethanol, as you mention in Brazil. The engine
is designed for mogas and really doesn't like Avgas.
My feeling is that the LAA are living in the past and if it's not Avgas it'
s
no good!! Well it's time to smell the coffee and get used to the here and
now. 10% ethanol is coming and I'll be using it.
It might mean changing the rubber more often but that's still much more
affordable than having to use Avgas.
Obviously just my humble opinion.
Cheers
Steve
GSTES
XS Trigear 912s..... nearly finished!!
_____
From: owner-europa-list-server@matronics.com
<mailto:owner-europa-list-server@matronics.com>
<owner-europa-list-server@matronics.com
<mailto:owner-europa-list-server@matronics.com> > on behalf of
JonathanMilbank <jdmilbank@yahoo.co.uk <mailto:jdmilbank@yahoo.co.uk> >
Sent: Thursday, 18 March 2021, 21:35
Subject: Europa-List: Ethanol in fuel. What about Brazil?
<mailto:jdmilbank@yahoo.co.uk> >
We in the UK are faced with the prospect of ethanol content in fuel being
raised in September from 5% to 10%. About 10 or so years ago (or was it
longer?) this whole subject got debated to death, with the LAA Light
Aircraft Association taking the position that we should always check each
fuel batch for ethanol before pouring it into our fuel tanks. The test usin
g
a glass test tube with about 1" of water in the bottom, noting its level,
then adding about 4 X as much fuel before shaking well and allowing to
settle to see if the water level had apparently risen, was not particularly
accurate and I never saw the water level rise.
The LAA's understandable position then was "If you find evidence of ethanol
in fuel, then don't use it!" This position is very unlikely to change, whic
h
will mean that Rotax engines should either use avgas or UL91. For those of
us living in god-forsaken northern latitudes, neither of these fuels are
available and it would be economically prohibitive to either import them to
our remote airfields or to fly to the nearest large airport to refuel, whil
e
simultaneously incurring landing fees and handling charges of =C2=A3200!
Obviously (at least to me) Europas should cope with 10% ethanol in fuel,
because I believe that at least one, maybe more Europas in Brazil were usin
g
fuel with ethanol having well in ecxess of 20%. Seemingly our "plastic" fue
l
tanks, automotive fuel lines and carburettors are unfased by ethanol.
Please correct me if I'm wrong about Brazil and let me know whether ethanol
is to blame for any fuel tank failures in Europas. Thank you.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=501000#501000
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| Subject: | Two ignitions on Rotax |
Hi Group
Curious, is there some unwritten general labeling of Rotax 914 ignition A and B
to which one should be Left and Right?
If not will use:
Right=R=Retarded=B=24BTDC?
Left=L=Less Retarded (Advanced)=A=26BTDC?
Thx. Ron P.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=501031#501031
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| Subject: | Re: Two ignitions on Rotax |
Ron,
FWIW, I just labeled mine as IGN A and IGN B.
There really isn=99t a =9CLEFT or RIGHT.=9D
I guess you could label them IGN TOP and IGN BOTTOM and stack the
switches the same way.
Blue skies & tailwinds,
Bob Borger
Europa XS Tri, Rotax 914, Airmaster C/S Prop.
Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP, Hercules
Prop.
3705 Lynchburg Dr.
Corinth, TX 76208-5331
Cel: 817-992-1117
rlborger@mac.com
> On Mar 20, 2021, at 9:48 AM, rparigoris <rparigor@hotmail.com> wrote:
>
>
> Hi Group
> Curious, is there some unwritten general labeling of Rotax 914
ignition A and B to which one should be Left and Right?
> If not will use:
> Right=R=Retarded=B=24BTDC?
> Left=L=Less Retarded (Advanced)=A=26BTDC?
> Thx. Ron P.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=501031#501031
>
>
>
>
>
>
>
>
>
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| Subject: | Two ignitions on Rotax |
Ron,
It doesn't matter as long as you know and write it down in your wiring book/logs.
I use top box is A/Left on the ignition switch and bottom is B Right on ignition
switch.
Just log it and make sure you mark the ignition wires also so when doing maintenance
10 years down the road, you can tell, because you sure as heck won't remember.
I can't tell you how many times I have gone back to my laptop (or phone) and reviewed
what pin went to what wire bundle to what instrument. I work tirelessly
to keep my modifications, changes, upgrades all logged and the wiring book up
to date. From the Airmaster Propeller back to the rudder trim. Document what
you do.
The mind is a terrible thing and the one I miss the most.
Best Regards,
Bud Yerly
-----Original Message-----
From: owner-europa-list-server@matronics.com <owner-europa-list-server@matronics.com>
On Behalf Of rparigoris
Sent: Saturday, March 20, 2021 10:48 AM
Subject: Europa-List: Two ignitions on Rotax
Hi Group
Curious, is there some unwritten general labeling of Rotax 914 ignition A and B
to which one should be Left and Right?
If not will use:
Right=R=Retarded=B=24BTDC?
Left=L=Less Retarded (Advanced)=A=26BTDC?
Thx. Ron P.
Read this topic online here:
https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fforums.matronics.com%2Fviewtopic.php%3Fp%3D501031%23501031&data=04%7C01%7C%7C4f360b6e5763431a36f608d8ebafc5a1%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637518487454857002%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=EE%2BTSMyOk%2BRi64KZC%2BqAYOCfKKqxjkaePJrXSf1WtjA%3D&reserved=0
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| Subject: | Re: Two ignitions on Rotax |
On 2021-03-20, at 14:48, rparigoris <rparigor@hotmail.com> wrote:
> Curious, is there some unwritten general labeling of Rotax 914 ignition A and
B to which one should be Left and Right?
> If not will use:
> Right=R=Retarded=B=24BTDC?
> Left=L=Less Retarded (Advanced)=A=26BTDC?
Ron, anyone - I have labelled my 912ULS ignition switches A and B corresponding
to the ignition modules. I used separate toggle switches rather than the typical
keyswitch because I seem to recall that someone said the 912S starts better
on one particular magneto.
However, I now cant find a reference to that assertion. I do find that the Rotax
heavy maintenance manual says that the 912 timing is the same for both ignition
circuits (26 BTDC), but different on the 914 (A 26 BTDC, B 22 BTDC) so I am
beginning to think that I misremembered!
Any observations on the topic welcome.
in friendship
Rowland
| Rowland Carson ... that's Rowland with a 'w' ...
| <rowlandcarson@gmail.com> http://www.rowlandcarson.org.uk
| Skype, Twitter: rowland_carson Facebook: Rowland Carson
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| Subject: | Start 914 on A, B or both? |
Hi Group
When starting a 914, is it worth it to start only on Ignition B where advance is
22 BTDC? This would be a little less advance compared to Ignition A where advance
is 26 BTDC. Perhaps less chance of kickbacks?
I don't have soft start.
I have heavy duty starter, Earth-X 680C and Airmaster.
I don't have the very old 914 ignition modules with different RPM and timing at
lower RPMs, mine has pretty good wire strain relief from factory.
Or start on both A+B Ignitions?
Perhaps get engine cranking with ignition off till max starter RPM?
I have B&C SD20S on vacuum pad, is it worth it to start with field off?
I have a B&C AVC1 regulator for internal generator, is it worth it to start with
no power going to AVC1 which will keep internal generator dead?
Thx.
Ron P.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=501035#501035
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| Subject: | Re: Two ignitions on Rotax |
Hi Group
Thank you for replies.
Rowland, the 914 ignition modules are the same but A is more advanced than B.
I have a separate starter switch, but ignition is keyed with OFF-R-L-BOTH.
I would rather not have to modify switch plate.
I'm going to go with:
R=Retarded=B
L=Less Retarded=A
Ron P.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=501036#501036
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| Subject: | 914 Servo Problem -- broken copper wiper -- is there a fix? |
The picture shows the inside of my TCU wastegate servo where the tip of one wiper
has broken off and is now stuck against (perhaps with dielectric grease) what
appears to be a screen printed resistor that is used by the TCU to measure
servo position.
The symptom was a jammed wastegate cable and a blinking orange TCU light that appears
about 6 seconds after power up (not immediately like what happens with
a disconnected sensor). After I removed the jammed cable from the servo wheel,
the servo rotates "too far" on power-up -- clockwise past the cable mount before
returning to the start position. No wonder the servo and cable were jammed.
When I opened the servo, the broken copper wiper was obvious.
Has anyone else seen this? Can I buy a gear with the copper wipers, or maybe just
the wipers themselves? This happened suddenly: 2 weekends ago everything
was perfect, last weekend -- blinking light. This weekend -- disassemble until
problem found. I can't imagine that I'm the only one with what amounts to a
potentiometer with a bad wiper. This is certainly not a $500 failure (cost of
new servo). Thanks.
--------
N914TX
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=501039#501039
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| Subject: | Re: 914 Servo Problem -- broken copper wiper -- is there |
a fix?
Hi PCahill Your picture didn't come through. I took a look and page 50 and 51 of Heavy Maintenance 76-00-00 https://www.cps-parts.com/cps/pdf/d05014.pdf gives value of potentiometer you need to know.
I would call Rotax Center and see if they can get parts, if not can they rebuild
it for you?
Perhaps you can locate a good used one? I did a quick search and found:
https://www.ebay.com/p/10008622325
I don't know what the thing looks like, but you know the values from the manual,
perhaps you can buy the part? Look at big 4? Mouser, Allied, Newary and Digi-key.
Since you know the values, perhaps you can rig up an external potentiometer. Perhaps
you could drive off cable if it has correct throw? If not turn a barrel
the precise diameter and drive a cable? Or make a servo arm the precise length?
I ran into a problem with my cowl flap. The Actonix linear servo had an internal potentiometer. I purchased their display that has a severe design flaw and after 2 attempts burned up internal wiring to potentiometer. I ended up installing a Ray Allen external potentiometer to one of their displays. Works great: http://www.rayallencompany.com/products/indsens.html they call it a position sensor. This is to give you an idea to use an external position sensor.
I took Buds advise and have the cable tail of my Servo follow on into a piece of
plastic tube:
https://1drv.ms/u/s!Ah1S270Nwg9V3UQweNiOl3_VYcum
If you could match the required values using a long tail to drive position sensor,
could be very nice. You could probably trim values a little with resistors.
If not lucky, obtaining a sensor with correct values and making a barrel with
precise diameter needed to drive a cable would probably be my second choice.
Here's a pic of install of external sensor on my cowl flap:
https://1drv.ms/u/s!Ah1S270Nwg9V3HM-hjioId6wjy9L
sensor on left side. I needed to position the pin a precise distance from flap
pivot. Works great (on ground thus far). BTW the cowl flap closes 100% and opens
with trail edge hanging down in airstream about same angle as my old 1948 Cessna
170 had aft side of cowl hanging in breeze:
https://1drv.ms/u/s!Ah1S270Nwg9V2HOfKEwvGS64xgPO
Ron P.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=501041#501041
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| Subject: | Re: Two ignitions on Rotax |
Ron,
Never thought of that logic. It works. But...Retarded....Is that being politically
correct? Hmmm.
Keep in mid that your 914 doesn't have the soft start issues of the 912S early
versions (without the soft start ignition or add on box). Don't confuse apples
and oranges.
Keep the battery strong and AvGas or really fresh car gas and the 914 will start.
If it every doesn't want to start, its the plugs normally. If you get them
wet and cranking voltage drops to 9 or so volts cranking, it won't go.
Follow common sense, adjust the carbs properly, keep clean plugs, fresh gas and
it will start quickly. If it cranks on and on. STOP. Turn off the master,
jump it and allow the ignition circuit timer to reset.
If you let the plugs get dirty or even old or use old car gas, you will more than
likely have starting issues.
My troubleshooting guide misses the point of being specific about the 914. As the
kids say "My Bad". I should have included a picture of where I set my throttle
plate after a carb rebuild. If the plate is too far opened or closed it
doesn't like to start either.
I know you know that the 914 fires top plugs on one module and bottom on the other.
The 914 is a different animal about starting and running smoothly than the
older 912S.
Rarely do I see a 914 ever kick back. It just won't start if the RPM isn't above
about 250. Heck mine won't start below 300 with old plugs. If you can count
the blades going by, it ain't gonna start in the cold or if the plugs are dirty
or wet. Just stop and get a charge or a good jump, consider changing plugs
at 25 hours. I did not beat this home in my troubleshooting guide either.
"My Bad."
Used plugs can be cleaned but not just brushed off with a plug cleaner. The problem
is with our anemic spark system and the plugs themselves. The area from
the electrode down the ceramic insulator and up the side wall to the plug exterior
gets a bit of carbon, or lead and this tends to ground out the electrode
making for poor spark somewhere around 25 hours of pattern flying. I found that
an ultrasonic cleaner and ensuring the plugs are cleaned while in a vertical
position with the solution of detergent or carb cleaner filling the plug recess
fully, will clean out this trapped soot/carbon/lead and renew the plug sufficiently
for re-use. Time is money, so frankly plugs are cheap. I'm experimenting
with mine to see how long my cleaned plugs work. I'll report more later,
but I figure it takes an hour of ultrasonic cleaning to get them really like
new. Is that worth the $35 for 8 new plugs? We'll see.
Simple Green detergent makes the plugs really bright and shiny, and carb cleaner
works a bit faster and leaves the plug metal a golden tan. Ah choices.
Sorry I didn't clean up my guide better.
Best Regards,
Bud Yerly
-----Original Message-----
From: owner-europa-list-server@matronics.com <owner-europa-list-server@matronics.com>
On Behalf Of rparigoris
Sent: Saturday, March 20, 2021 3:02 PM
Subject: Europa-List: Re: Two ignitions on Rotax
Hi Group
Thank you for replies.
Rowland, the 914 ignition modules are the same but A is more advanced than B.
I have a separate starter switch, but ignition is keyed with OFF-R-L-BOTH.
I would rather not have to modify switch plate.
I'm going to go with:
R=Retarded=B
L=Less Retarded=A
Ron P.
Read this topic online here:
https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fforums.matronics.com%2Fviewtopic.php%3Fp%3D501036%23501036&data=04%7C01%7C%7C32892c40949742f2959008d8ebd327af%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637518639419436971%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=fQaAMPux3nha3e%2BuufXASkUZenyUgX%2Ba4IyJyLcpOYY%3D&reserved=0
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| Subject: | Re: 914 Servo Problem -- broken copper wiper -- is there |
a fix?
Photo didn't attach on first try
Also posted to Rotax-Owner -- photo ok there
--------
N914TX
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http://forums.matronics.com/viewtopic.php?p=501043#501043
Attachments:
http://forums.matronics.com//files/img_2588_cropped_667.jpg
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| Subject: | 914 Servo Problem -- broken copper wiper -- is there |
a fix?
Paul,
No, not this specifically.
I had a wiper wear through and begin to hesitate. $500 and I was flying again.
Check ebay as there are usually a few on there. Typically about $150-$250 and
good for parts or sometimes good for a replacement. But check the part number.
The Skido Rotax 914 marine engine used the same servo but you don't normally see
these for sale.
Best Regards,
Bud Yerly
-----Original Message-----
From: owner-europa-list-server@matronics.com <owner-europa-list-server@matronics.com>
On Behalf Of PCahill
Sent: Saturday, March 20, 2021 7:01 PM
Subject: Europa-List: 914 Servo Problem -- broken copper wiper -- is there a fix?
The picture shows the inside of my TCU wastegate servo where the tip of one wiper
has broken off and is now stuck against (perhaps with dielectric grease) what
appears to be a screen printed resistor that is used by the TCU to measure
servo position.
The symptom was a jammed wastegate cable and a blinking orange TCU light that appears
about 6 seconds after power up (not immediately like what happens with
a disconnected sensor). After I removed the jammed cable from the servo wheel,
the servo rotates "too far" on power-up -- clockwise past the cable mount before
returning to the start position. No wonder the servo and cable were jammed.
When I opened the servo, the broken copper wiper was obvious.
Has anyone else seen this? Can I buy a gear with the copper wipers, or maybe just
the wipers themselves? This happened suddenly: 2 weekends ago everything
was perfect, last weekend -- blinking light. This weekend -- disassemble until
problem found. I can't imagine that I'm the only one with what amounts to a
potentiometer with a bad wiper. This is certainly not a $500 failure (cost of
new servo). Thanks.
--------
N914TX
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| Subject: | Re: 914 Servo Problem -- broken copper wiper -- is there |
a fix?
Hi PCahill Now that I have seen the unit and heard from Bud a few ideas:
Ask Bud if he still has his old unit that may have a good set of brushes on gear
and buy it from him and put on your unit? Note: There may be different variations
of servo, I have no ideas what the differences are. Perhaps the gear/brushes
is the same?
Measure the thickness of copper on brush, procure same or similar from McMaster
or other:
https://www.mcmaster.com/copper-sheets
Cut off a good portion of remaining leg on broken brush and form the end to look
exactly like other brushes, then solder splice a piece of copper splint.
I would probably do the percussive maintenance trick on solder job. Take some of
the thinnest solder you can find, then pound it into a thin sheet and cut to
precise size of splint. Put some flux on both sides after cleaning copper immaculate
and make a few clamps to hold it in position. Use some thin SS welding
rod if you have it, if not bend up some paper clips. Start with a modified Omega
shape. Thy different sizes of clamp also different thickness paper clips or
welding rod. If you have a problem getting heat in there or getting your soldering
iron in position, use flame from cigarette lighter. I would wrap neighboring
brushes with a piece of aluminium foil to keep heat off them. we don't know
what sort of temper they may have.
You ultimately want about the same pressure on brush as others. Since you are splicing
and may not be using the exact same copper, you will probably end up a
bit stiffer? If that happens you can probably do like Shunts do. Start making
the width a little bit narrower at a time till pressure is the same.
If you need more tension, beat a piece3 of copper thinner, cut to size and splint.
Look very careful at other brushes for any cracks. Any defects smooth out.
Look very very carefully at the broken pieces and see if there is a defect that
caused a stress riser. If there is, perhaps contact Rotax and see if they can
be of assistance.
Ron P.
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