Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Lesson Learned

Matronics Email Lists Forum Index -> Kitfox-List

View previous topic :: View next topic

Author Message

davestapa(at)juno.com
Guest

Posted: Sun Jan 14, 2007 5:17 pm Post subject: Lesson Learned

This afternoon while working on my 5 with a 912 S I learned a Valuable

LESSON. My engine has been running extremely rough. (Only has just a

little over a hour on it.) I manually balanced carbs and did not help.

Tried pneumatically balancing carbs and engine was running so rough I

could not get the screw driver on the idle stop screws. We decided to

shut down and try turning screws with engine off to see if we could get

it close enough to try with engine running. When trying to restart the

battery final gave up. After charging for 45 minutes we were ready to try

again. My buddy in the cockpit said "why don't you pull it through a

couple of times to save battery (to pull fuel into the engine). Master

off, ignition switch off, and kill switches off. ( I had earlier in the

day pulled the prop through about 30 blades to burp the engine). I pulled

one blade when the engine caught with everything off. It probably only

ran for 2-3 seconds. The second blade brushed my nuckles. Fortunately I

still have all my body parts. Further investigation revealed that a wire

had come out of a connector on the ignition module and one ignition

system was not grounding. Fixed that, balanced carbs and now she is

smooth as silk. Sorry to be so long winded, but I thought this was

important. DON" EVER LET ANYONE CONVINCE YOU THAT YOU CAN'T PULL A GEARED

ROTAX ENGINE FAST ENOUGH TO CREATE SPARK. From now on I will remember my

training and consider the ignition live at all time when around the prop.

Next time I burp it I will do so as if I'm propping a non starter

airplane. Will take longer, but safer. This thing might fly real soon.



David Estapa

Woodstock, GA

S5TD, N97DE

aldaniels(at)fmtcblue.com
Guest

Posted: Sun Jan 14, 2007 9:26 pm Post subject: Lesson Learned

Holy C***  I could have been killed doing what I have been doing. I had 

understood that it was impossible to get a spark from  that system by 

hand.  Sure am happy you were not hurt.



David Estapa wrote:

 	  Quote: 	
		   

 This afternoon while working on my 5 with a 912 S I learned a Valuable

henrysfork1(at)msn.com
Guest

Posted: Mon Jan 15, 2007 5:56 am Post subject: Lesson Learned

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]-->  When doing my run up I check the right mag, the left mag, then shut  down both mags. This is an easy check to help identify a problem. 

  

 Dee Young

 Model II

  

 Do Not Archive



   [quote][b]

rjdaugh

Joined: 30 Aug 2006
Posts: 195

Posted: Mon Jan 15, 2007 8:06 am Post subject: Lesson Learned

I too will be much more careful pushing the oil into the tank to check level

prior to starting. I do do the mag check every flight.



Thanks David!



Randy



.           



--

_________________
Randy
Kitfox 5/7 912S
Black Hills, South Dakota

kitfoxfugit(at)yahoo.com
Guest

Posted: Mon Jan 15, 2007 11:26 pm Post subject: Lesson Learned

One time the battery was dead, so, being used to

Aeroncas and Taylorcrafts etc, I just hand propped the

912UL.  It started right up.  You have to be even more

careful than with a small Continental because the

Continental kind of sputters to a start while the

Rotax lights off fast and has 3 blades coming round

quick.  A defective ground might make it hot and a

defective throttle is supposed to cause the throttle

to default to full power.  So I guess the grounds and

throttle connection needs to be checked, but the real

lesson seems to be - like a loaded gun - be careful

and always treat it like it is live when turning it

over.  JA KF IV Speedster.

 

Don't pick lemons.

See all the new 2007 cars at Yahoo! Autos.

http://autos.yahoo.com/new_cars.html

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Tue Jan 16, 2007 5:55 am Post subject: Lesson Learned

Most Contis have an impulse starter.  Without going into how it works, what

it does is give a good solid spark each time the cylinders reach TDC or even

later as long as the rpm of the engine is below 300rpm.



When the engine is shut down you will hear the impulse couplings cut it...

that makes the engine sound like it's falling apart at the seams and has a

big piece of something hard rattling around inside the crank case.



With those engines you must be double careful the mags are grounded out.

Most GA pilots only pull the mix and hit the master before getting out of

plane.  Few will do a check to make sure the mag grounding leads are solid.

For that reason I carry a couple of jumper leads that I install on the

P-Lead post of the mags and also to a good ground.  If I had a nickel for

every time I have seen broken or disconnected P-Leads and ignition switches

turned on I'd be wealthy today.



Noel



[quote] --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

kitfoxmike

Joined: 05 Dec 2006
Posts: 373

Posted: Tue Jan 16, 2007 7:04 am Post subject: Re: Lesson Learned

Dave,

Your problem wasn't that your mags didn't work.  What the problem was is that you had the right conditions inside the engine, air and fuel, and when you turned(by hand) over the engine it dieseled, yup, if you would have manually had things grounded to prevent the mags from working the engine would have still fired.  



I've had mine fire like this after pulling the choke and having the mags off and letting it turn over for a count of 12.  When I turn the mags back on and try to start it doesn't want to hit on all 4 so I quickly turn the mags off and pull the choke and turn it over some more, the very first turn over will make the engine fire, but not start, it dieseled.



The accurance is perfectly normal, you had been try to start the engine on one mag because you stated that you found a wire off, reinstalled it and now it works fine.



Move on and learn from it.  As far as the pre turn over to burp the engine.  Fooy on that I don't do it.  What I do is,  only on a cold engine that hasn't been run for at least 24 hrs. is to rotate the prop no more that one complete turn(I'm checking for hydrolic lock) then I get in the plane after doing my other check list.  I pull the choke and leave the mags OFF, then I'll turn over the engine for a count of 4 in the summer and 12 in the winter, also I look at the oil pressure to make sure I have pressure.  I release the starter switch. Then I let go of the choke and turn on the mags and start the engine.  



This is not only the safest way to start the engine, but I find it less of a strain on my muscles.  



Hope this helps.



kitfoxmike

912ul

Dwayne

Joined: 15 Apr 2006
Posts: 13

Posted: Tue Jan 16, 2007 7:46 am Post subject: Re: Lesson Learned

Both of my 912 Speedsters start easily by hand propping. However they don't seem to charge if the battery was dead and they were started by propping them. It seems that the charging circuit has to have a bit of battery power to excite the charging system into putting out the 14 volts...? Is that right? To reiterate, the engine will always easily start by propping with no battery power (or very little) the engine will run fine but it will not charge and the electrical gauges and instruments won't work, but by jump starting, with zero charge time, everything will work and charge.

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Tue Jan 16, 2007 2:09 pm Post subject: Lesson Learned

What you have to do is to energize the field coils of your alternator before

it can produce any current.  If you battery is so far gone it won't even

energize the filed coils than I guess it's time to send it off to the

knackers.  If your battery is discharging while the engine is stopped try

installing a master switch to completely isolate the battery....  BTW some

planes are wired so the clock is always live.



Noel



[quote] --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

lcfitt(at)sbcglobal.net
Guest

Posted: Tue Jan 16, 2007 2:49 pm Post subject: Lesson Learned

Sorry, Noel, No field coils in a 912. Nor an alternator, unless the owner 

opted for the alternator upgrade.



Lowell



do not archive



---

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Tue Jan 16, 2007 4:06 pm Post subject: Lesson Learned

Generators usually use a permanent magnet to generate power.  While

alternators use a field coil.  When he said it wouldn't charge the battery

unless it had been boosted first that sure sounds like a field coil not

energizing.  



Some turbine starter generators also have to be flashed with forward current

to change form starter to generator.  Doubt you or I will ever see one in a

Kitfox.... Unless the next generation of planes are electric powered! 



Noel



[quote] --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

pwmac(at)sisna.com
Guest

Posted: Tue Jan 16, 2007 7:01 pm Post subject: Lesson Learned

I thought the R9xx engines used a permanent magnet alternator (called 

a generator by R) and these types require a small voltage to kick 

start them. So a dead battery would be a no charge. But then the 

starter would be a no go as well.

Paul

==================

At 04:04 PM 1/16/2007, you wrote:

[quote]



Generators usually use a permanent magnet to generate power.  While

alternators use a field coil.  When he said it wouldn't charge the battery

unless it had been boosted first that sure sounds like a field coil not

energizing.



Some turbine starter generators also have to be flashed with forward current

to change form starter to generator.  Doubt you or I will ever see one in a

Kitfox.... Unless the next generation of planes are electric powered!



Noel



 > --

rjdaugh

Joined: 30 Aug 2006
Posts: 195

Posted: Tue Jan 16, 2007 7:44 pm Post subject: Lesson Learned

The 912S does have an alternator.  I kept running down my battery in early

tests, because I neglected the wire to energize the field.  Once I put that

in place all worked well, recharging the battery.



Randy



.           

--

_________________
Randy
Kitfox 5/7 912S
Black Hills, South Dakota

Dwayne

Joined: 15 Apr 2006
Posts: 13

Posted: Tue Jan 16, 2007 7:47 pm Post subject: Re: Lesson Learned

I would bet my $$ on your statement Paul because I have seen three different 912s do the exact same thing that I stated (dead battery, prop start and no charge) and NO the battery wasn't bad it had only discharged from something not being turned off.......

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Tue Jan 16, 2007 8:22 pm Post subject: Lesson Learned

The guy who made the original post said something about hand propping.  



Turbine starter generators require a shot of current to kick-start the

generator function they call it flashing (I believe) the armature.  I should

look that up again.  



Noel



[quote] --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

pwmac(at)sisna.com
Guest

Posted: Wed Jan 17, 2007 8:10 am Post subject: Lesson Learned

I am not so smart as this has been discussed on the aeroelectric list 

many times. The Jab has the same alternator and both are way 

undersized for typical needs.

Regards, Paul

===========

At 07:47 PM 1/16/2007, you wrote:

 	  Quote: 	
		  



I would bet my $$ on your statement Paul because I have seen three 

different 912s do the exact same thing that I stated (dead battery, 

prop start and no charge) and NO the battery wasn't bad it had only 

discharged from something not being turned off.......





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=88206#88206

kitfoxmike

Joined: 05 Dec 2006
Posts: 373

Posted: Wed Jan 17, 2007 9:05 am Post subject: Re: Lesson Learned

Not to get weard here, but how did we get on charging systems, when the original post talked about the engine firing up when the mags were turned off.

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Wed Jan 17, 2007 10:08 am Post subject: Lesson Learned

A fellow made a post that his engine wasn't charging under certain

circumstances.  Yes the subject should have been changed.



Noel



Do not archive



[quote] --

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

Display posts from previous:

	Matronics Email Lists Forum Index -> Kitfox-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum