 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
kerrjohna(at)comcast.net
Guest
|
 Posted: Wed Feb 01, 2006 7:47 am Post subject: weak compression |
 |
|
Bob Robertson....
When pulling through the prop on my 912UL, every fourth compression stroke seems to offer less resistance than the other three. I have not done a compression check but am wondering what the toubleshooting steps aught to be. I'll remind you that the rocker arm replacement has not been completed on this engine.
John Kerr
700 + hours
Bob Robertson....
When pulling through the prop on my 912UL, every fourth compression stroke seems to offer less resistance than the other three. I have not done a compression check but am wondering what the toubleshooting steps aught to be. I'll remind you that the rocker arm replacement has not been completed on this engine.
John Kerr
700 + hours
| | - 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 |
|
 |
lcfitt(at)sbcglobal.net
Guest
|
| Posted: Wed Feb 01, 2006 4:35 pm Post subject: weak compression |
|
|
John, this is a common occurance with my engine. When we were on our way
to Oshkosh two summers ago, after a fuel stop at Afton , Wyoming, I climbed
in to move the airplane to a tiedown spot and the starter turned spun the
engine just like a turbine - four stuck valves. We ran two quarts of ATF
through it and no stuck valves since. The ATF was a substitute for Marvel
Mystery Oil as it was not available in town.
My guess that on occasion a valve will not seat completely when cold and as
I mentioned it is fairly common with my engine. However, when I do the
compression check - warm engine - at my annual condition inspection, the
compression on all four cylinders has always been well within limits - 79-80
psi.
Question, do you run on autogas or avgas or a combination.
Lowell
---
| | - 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 |
|
|
kerrjohna(at)comcast.net
Guest
|
| Posted: Thu Feb 02, 2006 9:38 am Post subject: weak compression |
|
|
Lowell, thanks for the reply. I rarely run avgas--on cross countrys when mogas is not available and I always use blended oil.
I admit to being a little goosey because Bob Robertson and I sort of came to the conclusion to not change out the rocker arm shaft way back when. As I look over the engine log books I have noted that I am using less pitch now than back in '96 although the indicated air speed is still right at 105 mph at 5200 rpm. Not sure that that makes any sense.
I have been flying the new RV9 for the past 6 weeks when weather permits but when I flew the 'Fox last week I remembered why it was so danged much fun (and guilt free as well).
John
-------------- Original message --------------
From: "Lowell Fitt" <lcfitt(at)sbcglobal.net>
[quote]
John, this is a common occurance with my engine. When we were on our way
to Oshkosh two summers ago, after a fuel stop at Afton , Wyoming, I climbed
in to move the airplane to a tiedown spot and the starter turned spun the
engine just like a turbine - four stuck valves. We ran two quarts of ATF
through it and no stuck valves since. The ATF was a substitute for Marvel
Mystery Oil as it was not available in town.
My guess that on occasion a valve will not seat completely when cold and as
I mentioned it is fairly common with my engine. However, when I do the
compression check - warm engine - at my annual condition inspection, the
compression on all four cylinders has always been well within limits - 79-80
psi.
Question, do you run on autogas or avgas or a combination.
Lowell
---
| | - 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 |
|
|
|
|
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
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
