Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

912 Vibration

 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Kitfox-List
View previous topic :: View next topic  
Author Message
7suds(at)Chartermi.net
Guest
PostPosted: Wed Jan 25, 2006 7:29 pm    Post subject: 912 Vibration Reply with quote
Group,
A friend of mine is working on a Pulsar with a 912UL 80 hp. It dropped a
wheel off the runway when turning around and had a slight prop strike. The
prop was a GSC 2 blade wood ground adjust. Upon inspection there was no
evidence of the strike so the prop was removed and sent to the Mfg. for
inspection which revealed micro fractures to the prop end. The prop was
replaced and there is now a slight vibration at low RPM, higher RPM seems to
be smoother. The prop was removed and balance checked, balanced and replaced
but vibration still there. The question he would like to ask is what do you
feel he should look at, check, replace in the motor? Also, are the 912
cranks solid or are they pressed together?
Thanks for any direction I can pass on,
Lloyd

- The Matronics Kitfox-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List
Back to top
Jim Shumaker



Joined: 09 Jan 2006
Posts: 106
PostPosted: Wed Jan 25, 2006 10:12 pm    Post subject: 912 Vibration Reply with quote
lloyd

It is not likely that the engine was damaged due to a prop strike with a wooden prop. Wooden props usually shatter before they transmit damaging forces to the engine. Try a different prop. Also look for a difference in tracking along different sections of the blades. That is, if both blades are set at the same angle using the GSC protractor, they may not be set at the same angle. Check for proper tracking of the prop and check it for tracking at a couple of different points. They blades may not be a perfect match at all points along the blades.

Jim Shumaker

Cudnohufsky's <7suds(at)Chartermi.net> wrote:


Group,
A friend of mine is working on a Pulsar with a 912UL 80 hp. It dropped a
wheel off the runway when turning around and had a slight prop strike. The
prop was a GSC 2 blade wood ground adjust. Upon inspection there was no
evidence of the strike so the prop was removed and sent to the Mfg. for
inspection which revealed micro fractures to the prop end. The prop was
replaced and there is now a slight vibration at low RPM, higher RPM seems to
be smoother. The prop was removed and balance checked, balanced and replaced
but vibration still there. The question he would like to ask is what do you
feel he should look at, check, replace in the motor? Also, are the 912
cranks solid or are they pressed together?
Thanks for any direction I can pass on,
Lloyd

- The Matronics Kitfox-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

_________________
Jim Shumaker
Back to top
View user's profile Send private message
7suds(at)Chartermi.net
Guest
PostPosted: Thu Jan 26, 2006 3:16 pm    Post subject: 912 Vibration Reply with quote
Thanks Jim, we will definitely do that.
---

- The Matronics Kitfox-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List
Back to top
ruebd(at)skymail.csus.edu
Guest
PostPosted: Thu Jan 26, 2006 3:46 pm    Post subject: 912 Vibration Reply with quote
Lloyd

Remember that the Rotax 912 uses a gearbox for final drive to the
propeller, so if any damage was sustained by the prop strike, it would
be to the output shaft of the gearbox, not the engines crankshaft. Even
though wooden props tend to not transmit damage, it is still possible,
and it sounds like your friend may have a bent propeller shaft. He
needs to have it checked by someone who can put a dial indicator on it.
Duane

--

- The Matronics Kitfox-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List
Back to top
Display posts from previous:   
Post new topic   Reply to topic    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


Powered by phpBB © 2001, 2005 phpBB Group