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Eugene Zimmerman

Joined: 10 Jan 2006
Posts: 392

Posted: Thu May 04, 2006 5:01 am Post subject: Rotax relapse

On May 4, 2006, at 12:23 AM, John Hauck wrote:



 	  Quote: 	
		   May not work for everyone, but it has worked for me, very

 satisfactorily.



 Take care,



 john h

 mkIII


	


John,

What do you mean "very satisfactorily" ?

How many trouble free hours total were you able to get from a two  

stroke 582 or 447?

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Thu May 04, 2006 5:39 am Post subject: Rotax relapse

| What do you mean "very satisfactorily" ?

| How many trouble free hours total were you able to get from a two

| stroke 582 or 447?

Wasn't talking about trouble free hours.  Was explaining how I prop a 

two and a four stroke, airplane and boat.  Best way I know how to do 

it with a fixed or ground adjustable prop on airplane and boat.



Propping a two stroke airplane is especially critical to load the 

engine correctly to get EGT and CHT in the green.



Trouble free and two strokes don't really go together.  To me, two 

strokes are like race engines.  Get'em set up to run, they perform 

well, but demand a lot of attention.  Even then, the dreaded "piston 

seizure" is always lurking, waiting to strike.



The fact that I stopped buying and flying two strokes in 1993, may 

help explain my position.



There are always going to be a couple folks that have flown a two 

stroke 500, 1,000 hours or more without any problems and little 

maintenance.  However, I believe them to be in a very, very small 

minority.



Its fine if you all disagree with my experience with two strokes. 

Maybe I was one of the unlucky ones.  Maybe I didn't know what I was 

doing.  Initially, I did not have much knowledge of the two stroke.  I 

discovered, in flight, through experimentation, the phenomenon of prop 

loading and unloading, and how it affected the EGT.  At a constant 

throttle setting, push the nose over, the EGT climbs - pull the nose 

up and the EGT falls.  Low midrange power descents, EGT heads for the 

red line.  Full power, full throttle applications and the EGT comes 

back down.  Didn't have the opportunity to learn the above from books. 

Accidentally came upon it while playing with my Kolb Ultrastar.



However, even with all their associated problems, I never hesitated to 

hop in my two stroke powered Kolb, point the nose where I wanted to 

go, and head out for adventure.  When the opportunity for a four 

stroke came along, it simply made those adventures a lot for 

comfortable.



Some improvements have been made to our two strokes today, compared to 

20+ years ago.  Primarily, CDI ignition, better bearings, i.e., 

cageless wrist pin bearings.



john h

mkIII



PS:  Should be landing at MV two weeks from today, I hope.

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

Eugene Zimmerman

Joined: 10 Jan 2006
Posts: 392

Posted: Thu May 04, 2006 9:55 am Post subject: Rotax relapse

On May 4, 2006, at 9:38 AM, John Hauck wrote:



 	  Quote: 	
		   Wasn't talking about trouble free hours.  Was explaining how I prop a

 two and a four stroke, airplane and boat.  Best way I know how to do

 it with a fixed or ground adjustable prop on airplane and boat.



 Propping a two stroke airplane is especially critical to load the

 engine correctly to get EGT and CHT in the green.



 Trouble free and two strokes don't really go together.

snip
	


 	  Quote: 	
		  

 Some improvements have been made to our two strokes today, compared to

 20+ years ago.  Primarily, CDI ignition, better bearings, i.e.,

 cageless wrist pin bearings.


	




I agree,

but it is possible to load a two-stroke anywhere within its designed  

operational rpm range and,  with proper mixture control,  have good  

success.



Our two-strokes are much more finicky because they get almost twice  

the hp of a four-stroke from a given displacement, and because they  

depend heavily on pulse tuning to breath properly. Any change in rpm  

significantly effects the characteristic of the engine to breath  

efficiently. Without fuel injection it is almost impossible to  

optimize the fuel mixture for every possible load variation and  

throttle position.

The key to success with a two-stroke is to understand these  

characteristics and always operate them within their narrow band of  

performance requirements

Two-strokes are not good at everything,  but they remain unbeaten at  

what they are  good at.

That is hp/weight for our planes.

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Thu May 04, 2006 11:40 am Post subject: Rotax relapse

|

| Our two-strokes are much more finicky because they get almost twice

| the hp of a four-stroke from a given displacement,



Gene/Gang:



Yes, and they lack the ability to cool themselves as the 4 strokes. 

The 912 is primarily oil cooled, although Rotax used water cooling to 

help cool the heads.  They wanted to go air cooling all the way, but 

because of the amount of heat produced by the little engine, the head 

cooling fins would have to have been to large a package for most 

enclosed applications.  The cylinders are entirely aircooled.



Along with cooling, that oil is also doing a good job of lubrication 

of the engine.



Two strokes rely heavily on air and fuel to cool themselves.  One 

reason the are not "fuel efficient".  Another is because they depend 

of other means for valving than the normal 4 stroke.  I know Jack Hart 

is adamant about making his two strokes fuel misers.  Without a doubt 

he loves the challenge of trying to make something out of the two 

stroke that it is not.  Considerable caution should be used when 

"leaning" a two stroke for fuel economy.  In addition to burning less 

fuel, the two stroke will put out a lot more power in an over lean 

condition than when it is running in the area of fuel richness for 

which it was designed.  Leaner, more power, more heat, less fuel and 

oil.  Be glad when Jack gets a little 4 stroke to play with on his FF. 

Then he can lean that little sucker out, power it down, and end up 

burning a gallon an hour.  



john h

mkIII

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Thu May 04, 2006 12:49 pm Post subject: Re: Rotax Relapse

 	  beauford(at)tampabay.rr.c wrote: 	
		  Kolbers and Kolbettes:



-- Running Amsoil Saber 100 to one, but I'm mixing it at 70 to one

-- Ran a test tank of Pennzoil AC 50 to 1, no change in problem



Brandon, FL 	




Amsoil 2 cycle oil is horrible stuff.  I dont care how they market the oil, 100 - 1 is not enough oil in the gas.  70 to 1 is not even enough.  Amsoil leaves behind a sticky mess and fouls plugs and makes rings stick.  Motorcycle guys that run 2 stroke bikes run other oils.



Amsoil is an inferrior product that relys on a pyramid sales network that sells everyone on the fact that it is better.  But Amsoil sucks, and never has held its own in the open market.



John Hawk is very correct, 2 stroke engines are unreliable and very prone to problems and failures.  They can be made to run under perfect conditions, but sooner or later engines encounter less than perfect conditions, shit happens.  Even motorcycles, boats and jetskis are going towards 4 stroke design now days.



I realize that choices for the firefly and firestar are limited, but if I flew one of those I would do my best to find a 4 stroke for it.  Maybe the HKS ???   Only a total idiot would not realize how far superior a 4 stroke is to a 2 stroke.



Michael A. Bigelow

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

David.Lehman

Joined: 10 Jan 2006
Posts: 265
Location: "Lovely" Fresno CA

Posted: Thu May 04, 2006 1:00 pm Post subject: Rotax Relapse

Total idiot here...

What 4 stroke will give me the power to weight ratio of my 503 and even mor=

e

importantly, for the price of a 503?...

DVD

do not disturb, oops...

do not archive...

On 5/4/06, JetPilot <orcabonita(at)hotmail.com> wrote:

 	  Quote: 	

 beauford(at)tampabay.rr.c wrote:

 > Kolbers and Kolbettes:

 >

 > -- Running Amsoil Saber 100 to one, but I'm mixing it at 70 to one

 > -- Ran a test tank of Pennzoil AC 50 to 1, no change in problem

 >

 > Brandon, FL

 Amsoil 2 cycle oil is horrible stuff.  I dont care how they market the

 oil, 100 - 1 is not enough oil in the gas.  70 to 1 is not even

 enough.  Amsoil leaves behind a sticky mess and fouls plugs and makes rin=

gs

 	  Quote: 	
		   stick.  Motorcycle guys that run 2 stroke bikes run other oils.

 Amsoil is an inferrior product that relys on a pyramid sales network that

 sells everyone on the fact that it is better.  But Amsoil sucks, and neve=

r

 	  Quote: 	
		   has held its own in the open market.

 John Hawk is very correct, 2 stroke engines are unreliable and very prone

 to problems and failures.  They can be made to run under perfect conditio=

ns,

 	  Quote: 	
		   but sooner or later engines encounter less than perfect conditions, shit

 happens.  Even motorcycles, boats and jetskis are going towards 4 stroke

 design now days.

 I realize that choices for the firefly and firestar are limited, but if I

 flew one of those I would do my best to find a 4 stroke for it.  Maybe th=

e

 	  Quote: 	
		   HKS ???   Only a total idiot would not realize how far superior a 4 strok=

e

 	  Quote: 	
		   is to a 2 stroke.

 Michael A. Bigelow

 --------

 "NO FEAR" -  If you have no fear you did not go as fast as you could have

 !!!

 Read this topic online here:

 http://forums.matronics.com/viewtopic.php?p=3D32828#32828

_________________
ô¿ô

"Both optimists and pessimists contribute to the society. The optimist invents the aeroplane, the pessimist the parachute."

--- George Bernard Shaw

Jim Baker

Joined: 30 Mar 2006
Posts: 181
Location: Sayre, PA

Posted: Thu May 04, 2006 1:38 pm Post subject: Rotax Relapse

 	  Quote: 	
		   100 - 1 is not enough oil in the gas.  


	




Damn! My engine isn't going to like that. I've run nothing but 106:1 since 

new. OMCand Orbital, who have run two stokes at upwards of 225:1 without 

deleterious effect,  won't be too happy either. 

Jim Baker

580.788.2779

Elmore City, OK

Eugene Zimmerman

Joined: 10 Jan 2006
Posts: 392

Posted: Thu May 04, 2006 2:55 pm Post subject: Rotax relapse

On May 4, 2006, at 3:39 PM, John Hauck wrote:



 	  Quote: 	
		   Be glad when Jack gets a little 4 stroke to play with on his FF.

 Then he can lean that little sucker out, power it down, and end up

 burning a gallon an hour.  


	


A gallon an hour is quite  

possible ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 

,,in a glider.  



All Jack needs is for "a gallon an hour" in his two-stroke  is for   

MissPfer to tow his little Firefly to altitude for some good ridge lift.

Eugene Zimmerman

Joined: 10 Jan 2006
Posts: 392

Posted: Thu May 04, 2006 3:09 pm Post subject: Rotax Relapse

On May 4, 2006, at 4:49 PM, JetPilot wrote:



 	  Quote: 	
		   I realize that choices for the firefly and firestar are limited,  

 but if I flew one of those I would do my best to find a 4 stroke  

 for it.  Maybe the HKS ???   Only a total idiot would not realize  

 how far superior a 4 stroke is to a 2 stroke.


	




The lighter the plane, the more superior a 2 stroke becomes.

A 40 hp 4 stroke on a legal ultralight firefly will shake the  

daylights out of the pilot and plane.

Gene Ledbetter

Joined: 10 Jan 2006
Posts: 20
Location: Cincinnati, OH

Posted: Thu May 04, 2006 3:17 pm Post subject: Re: Rotax Relapse

Beauford,



Sorry to get into the suggestion arena a little late but thought I might share one other possibility.  I installed a new 447 on my firefly last week after 320 hrs on the original engine.  The original engine was running perfectly but I decided to go ahead and install new rather than overhaul.  The difference in price was minor and I was able to buy a short block w/o electronics through solo aviation in Harrodsburg, KY.  Solo aviation also replaced the gear box springs and moved the electronics from the old engine to the new one.



Went on down to London and did the installation in Bryan's shop with a little over the shoulder help.



Brought the Firefly home and did the breakin on Tuesday without any problem.  Flew today for the first time and am very pleased with the performance.  Full throttle gives 6500rpm.  5800 rpm gives 375° cht and 1025 egt.  All in all, I'm very pleased and will retorque on my next visit and be ready for the summer flying. 



Now to my suggestion.  My original 447 had heating problems until the engine was really broken in.  However, I also changed the needle to an 11G2 size and continue to use that size.  Today's new engine performance was achieved with that needle.



Don't know if this will solve you problem but it's another suggestion...



Gene

_________________
Gene D.
2000 Firefly
330 Hours
New 447
Brakes, Ivo

beauford(at)tampabay.rr.c
Guest

Posted: Thu May 04, 2006 4:45 pm Post subject: Rotax Relapse

Brother Ledbetter:

Thankee much for the info about the needle you are using... Will keep

that in my notes and may try it before this saga is over.   I'm taking

the day off

from work tomorrow and plan to go fool around with the Nazi engine....

Will start

with the prop unload and adding enough oil to the mix to bring it to

50 to 1...

I know the prop will have some immediate effect on it, am just not

sure

whether it will be enough.  I flew this thing with the prop set

roughly where it

is now (6400 WOT) for the first 80 hours or so and never had temps

anywhere near

this high...  Of course that was before the new pistons and rings...

they could

well be a tad tighter than original, even though they were carefully

fitted by

the pros... If tightness is a factor, they should loosen up gradually

and the temps

should come down.



Interestingly enough, reliable sources have forwarded me some

references to

higher CHT  limits than I had previously seen for the 447... with an

absolute redline

of 480 and discussions about folks routinely operating them in the 400

to 425 range.

Makes me feel a little better, but I wonder about the oil coking up on

pistons and

rings at those temps...  I reckon I'll find out if mine don't come

down.



Best of luck with your new engine, Gene... hope it's a keeper.



Regards,

Beauford

FF#076

Brandon, FL



---

DAquaNut(at)aol.com
Guest

Posted: Thu May 04, 2006 5:52 pm Post subject: Rotax Relapse

In a message dated 5/4/2006 3:51:06 P.M. Central Standard Time,  

orcabonita(at)hotmail.com writes:

I  realize that choices for the firefly and firestar are limited, but if I 

flew  one of those I would do my best to find a 4 stroke for it.  Maybe the HKS  

???   Only a total idiot would not realize how far superior a 4  stroke is to 

a 2 stroke.



Michael A.  Bigelow





Yes  the  choices are limited!   The HKS is NOT a choice, as it weighs too 

much  for the firefly. Do You know of any reasonable choice other than a Rotax  

447?????????  Just bear in mind that the engine cannot weigh over about 80  

lbs with redrive.  Question for you-----------------   Why do you  feel the need 

to call other list members names???????????? 

 

 

               Ed Diebel     ( Firefly # 62  Just waiting for the 45  lb  

rotary engine to be available)

 

 

           Do Not  Archive!

ul15rhb(at)juno.com
Guest

Posted: Thu May 04, 2006 6:17 pm Post subject: Rotax Relapse

I've been running over 19 years with *unreliable* 2-stroke engines on my Firestar. How's this possible if they are so unreliable? I've had two of them, a 377 and a 447. This last one has never been overhauled in 450 hours.



Ralph

Original Firestar

19 years flying it

-- "JetPilot" <orcabonita(at)hotmail.com> wrote:


beauford(at)tampabay.rr.c wrote:

 	  Quote: 	
		   Kolbers and Kolbettes:

 

 -- Running Amsoil Saber 100 to one, but I'm mixing it at 70 to one

 -- Ran a test tank of Pennzoil AC 50 to 1, no change in problem

 

 Brandon, FL


	




Amsoil 2 cycle oil is horrible stuff.  I dont care how they market the oil, 100 - 1 is not enough oil in the gas.  70 to 1 is not even enough.  Amsoil leaves behind a sticky mess and fouls plugs and makes rings stick.  Motorcycle guys that run 2 stroke bikes run other oils.



Amsoil is an inferrior product that relys on a pyramid sales network that sells everyone on the fact that it is better.  But Amsoil sucks, and never has held its own in the open market.



John Hawk is very correct, 2 stroke engines are unreliable and very prone to problems and failures.  They can be made to run under perfect conditions, but sooner or later engines encounter less than perfect conditions, shit happens.  Even motorcycles, boats and jetskis are going towards 4 stroke design now days.



I realize that choices for the firefly and firestar are limited, but if I flew one of those I would do my best to find a 4 stroke for it.  Maybe the HKS ???   Only a total idiot would not realize how far superior a 4 stroke is to a 2 stroke.



Michael A. Bigelow



--------

&quot;NO FEAR&quot; -  If you have no fear you did not go as fast as you could have !!!





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=32828#32828





 

 

 

________________________________________________________________________

Try Juno Platinum for Free! Then, only $9.95/month!

Unlimited Internet Access with 1GB of Email Storage.

Visit http://www.juno.com/value to sign up today!

Richard Pike

Joined: 09 Jan 2006
Posts: 1671
Location: Blountville, Tennessee

Posted: Thu May 04, 2006 7:02 pm Post subject: Rotax Relapse

I bought a zero timed 582 with a new B box for $2800 from a

Rotax factory authorized rebuild center.

Please advise me of where I can get a 65 HP 4 stroke of similar weight

for less than twice the price so I won't need to feel like an inferior 

idiot.



Thanks,

Richard Pike

MKIII N420P (420ldPoops)



do not archive



JetPilot wrote:



 	  Quote: 	
		   

   

  Only a total idiot would not realize how far superior a 4 stroke is to a 2 stroke.



 Michael A. Bigelow



 --------

 &quot;NO FEAR&quot; -  If you have no fear you did not go as fast as you could have !!!





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=32828#32828

_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0

Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.

Jim Baker

Joined: 30 Mar 2006
Posts: 181
Location: Sayre, PA

Posted: Thu May 04, 2006 8:00 pm Post subject: Rotax Relapse

 	  Quote: 	
		   Only a total idiot would not realize how far superior a 4  stroke is to 

 a 2 stroke.


	


Damn! Again! My engine jus' doan like bein' talked to like that. I don't mind, 

but the fool engine thinks yer makin' fun of it and now it's all riled up. Now if 

you was to apologise, like I know you're gonna.........



Jim Baker

580.788.2779

Elmore City, OK

Possum

Joined: 12 Jan 2006
Posts: 112
Location: Georgia

Posted: Thu May 04, 2006 10:11 pm Post subject: Rotax Relapse

At 08:57 PM 5/4/2006, you wrote:

 	  Quote: 	
		  

  Of course that was before the new pistons and rings...

they could

well be a tad tighter than original, even though they were carefully

fitted by

the pros... If tightness is a factor, they should loosen up gradually

and the temps

should come down.


	


I'll quote some old articles on the 447:



When the CHT runs hot and the EGT gauge is normal.



A lack of lubrication will only show on the "CHT gauge."

This condition will not be indicted by an EGT gauge.

Nor will the lack of cooling air caused by a slipping fan belt

or partial blockage of the intake opening.

The EGT gauge will, however, indicate an air leak or lean

mixture long before the CHT gauge.

Piston and rings tighter than specs, of course,

will only show on the CHT.

These articles also talk about "preignition" and timing showing

both gages running hotter.

Are they still putting point ignitions on the 447's ?

That is one of the reasons I switched to the 503.

Sully



http://www.800-airwolf.com/pdffiles/ARTICLES/part12.pdf



http://www.800-airwolf.com/pdffiles/ARTICLES/part38.pdf



http://www.800-airwolf.com/pdffiles/ARTICLES/part24.pdf

Possum

Joined: 12 Jan 2006
Posts: 112
Location: Georgia

Posted: Thu May 04, 2006 10:30 pm Post subject: Rotax Relapse

At 02:08 AM 5/5/2006, you wrote:

 	  Quote: 	
		  



I'll quote some old articles on the 447:



When the CHT runs hot and the EGT gauge is normal.



A lack of lubrication will only show on the "CHT gauge."

This condition will not be indicted by an EGT gauge.

(Nor will the lack of cooling air caused by a slipping fan belt

or partial blockage of the intake opening.)


	


Maybe should clarify - "the lack of cooling air caused by a slipping fan belt

or partial blockage of the intake opening will only show up on the CHT gage."

beauford(at)tampabay.rr.c
Guest

Posted: Fri May 05, 2006 1:47 am Post subject: Rotax Relapse

Thanks, Brother Sullivan...

Excellent C.P.S. material and I'll sure save it...

No, the 447 now has the same Ducatti electronic ignition as the 503...

but it

only has one of them.



I'll give you a follow-up report later today... this ought to be

interesting... if it

kills me, George Alexander gets my Timex.



Regards,

Beauford

Do Not Archive

---

Eugene Zimmerman

Joined: 10 Jan 2006
Posts: 392

Posted: Fri May 05, 2006 4:12 am Post subject: Rotax Relapse

On May 5, 2006, at 6:00 AM, Beauford wrote:



 	  Quote: 	
		    if it

 kills me, George Alexander gets my Timex.


	




He deserves it . He is a good guy.

Hi Geo.

Eugene Zimmerman

Joined: 10 Jan 2006
Posts: 392

Posted: Fri May 05, 2006 4:14 am Post subject: Rotax Relapse

On May 5, 2006, at 6:00 AM, Beauford wrote:



 	  Quote: 	
		   I'll give you a follow-up report later today... this ought to be

 interesting..


	




I'd try a higher octane fuel, especially in your climate.

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