Earthstar Forums

Mike does the hirth use the same motor mount plates as the Rotax 503?


Mike S

Thanks for the info Mark & Gary.

Mike S

I dont know if the motor plates are the same, Mark might be able to answer that. I'm sure they are very similer in design,the engine might be moved foward or aft for cg considerations.

In a message dated 11/18/2011 5:12:51 AM Pacific Standard Time,
sadowin@yahoo.ca writes:


Mike does the hirth use the same motor mount plates as the Rotax 503?

Mike S




No, but they are similar you are leaving a good friend by taking off your
503.
There is no better 2 cycle engine for your plane.
Happy Flying
Mark

Mark,

What is your recommendation for pitching a ground-adjustable Ivoprop on the 503
with 3:1 "C" gearbox on my JT2? Home airport elevation is 3200 and daytime temps
range from 50 in winter to 105 in summer.

I currently have it set so that max rpm in level flight at 5000 ft is 6300, to
provide engine loading at cruise. That makes my climb out in the 5600-5700 rpm
range.

I am now installing Greensky's HACman mixture adjustment system. Can I
safely change the pitch to get better climb and use the mixture control at
cruise to keep the EGTs proper?

I've also considered installing the Ivoprop in-flight adjustable hub. The plane
used to have that, but it broke and previous owner opted for ground-adjustable
hub to save money.

Thanks for your help. 
 Dick O'Reilly

In a message dated 11/18/2011 10:20:04 AM Pacific Standard Time,
dickoreilly@yahoo.com writes:


What is your recommendation for pitching a ground-adjustable Ivoprop on
the 503 with 3:1 "C" gearbox on my JT2? Home airport elevation is 3200 and
daytime temps range from 50 in winter to 105 in summer.

I currently have it set so that max rpm in level flight at 5000 ft is
6300, to provide engine loading at cruise. That makes my climb out in the
5600-5700 rpm range.

I am now installing Greensky's HACman mixture adjustment system. Can I
safely change the pitch to get better climb and use the mixture control at
cruise to keep the EGTs proper?

I've also considered installing the Ivoprop in-flight adjustable hub. The
plane used to have that, but it broke and previous owner opted for
ground-adjustable hub to save money.

Thanks for your help.

Dick O'Reilly


Hi Dick
I like to set up the pitch so that the engine will develop 5700 static rpm.

The electric IVO is almost a necessity for the 503. We are dealors and
could save you a little money if you bought it through us.

Be very careful with the mixture control. I wouldn't use it because I don't
trust my self to manage it and would sooner or later seize the engine.
Happy Flying
Mark

Dick, I will chime here, and Mark will probably ditto this. I found the optimum pitch to be about 14.5 degrees on the 68" 3-blade Ivo, running behind the 3:1 'C' box on my 503. My climbs are at similar rpm's to yours, and the flat-out wide open throttle (WOT), are also 6250-6300rpm, which is about the maximum torque and horsepower for the 503. I verified this by converting the ground adjust Ivo back to in-flight adjust, and by fine tuning the prop I found the fastest speeds to be those same rpm's. Gotta love those Ivo's, they make our airplanes kick butt for the money compared to the S-LSA's that cost $100K plus.

kb

Dick, earlier this year, I called the factory about my failed Ivo in-flight adjust that froze up after 275 hours use. They said they would replace the spool and jack-screw that had stripped threads for $92, if I would send the motor back. It came back all assembled, ready to put back on the airplane. Now I will re-lube the threads with white lithium grease every annual condition inspection, and maybe it won't fail again for a while. I found the optimum setting for the in-flight adjust, and rarely change it, although I love the fine pitch option for agressive climbs at short fields.

kb

Well lets just face it. Kess thinks its sexy Mark thinks its a blast to have that extra power. If John Wayne was a pilot he wouldn't fly no mambe pambe airplane engine, he would fly something with a growl!
I have to admitthe HKS Turbo does have a sound all its own.I like it.The computer fuel management would set you free from the jet guessing game. Don't get me wrong I am really learning to like my 503. You all know the trouble I had but it runs perfect now and has for a long time.I will probably exceed the 300 hours by the time I save the money for the Turbo. My mind, she's a made-a-up!
I like the visbility so much in my JT2 that I am going to sculpt a new dash that rounds off the corners so I have no obstructions at all. I will do it up in carbon fiber mounting the Garmin 796 right in the middle.
Fred

In a message dated 11/18/2011 3:06:03 PM Pacific Standard Time,
gayford@golden.net writes:

Well lets just face it. Kess thinks its sexy Mark thinks its a blast to
have that extra power. If John Wayne was a pilot he wouldn't fly no mambe
pambe airplane engine, he would fly something with a growl!
I have to admitthe HKS Turbo does have a sound all its own.I like it.The
computer fuel management would set you free from the jet guessing game.
Don't get me wrong I am really learning to like my 503. You all know the
trouble I had but it runs perfect now and has for a long time.I will probably
exceed the 300 hours by the time I save the money for the Turbo. My mind,
she's a made-a-up!
I like the visbility so much in my JT2 that I am going to sculpt a new
dash that rounds off the corners so I have no obstructions at all. I will do
it up in carbon fiber mounting the Garmin 796 right in the middle.
Fred




Hi Fred
796, Cool! like your ideas about the panel.
300 hrs is nothing to a 503 that is run in a gull and at the right temps,
like 1100 EGT or higher.
Happy Flying
Mark