 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
jbhart(at)onlyinternet.ne
Guest
|
 Posted: Fri Apr 24, 2009 6:55 am Post subject: Kolb-List: 503 low CHT’s dilemma! |
 |
|
At 05:12 AM 4/24/09 -0700, you wrote:
| Quote: |
Plugs: Old plugs not fouled but a little darker than I would like.
Installed new plugs.
|
| Quote: |
I decided then to try a smaller main jet. I took out the 155’s and put in
150’s. (I did not have 152’s). I tested again and topped out at 230* CHT
|
and 1150* EGT at full throttle. RPM’s were 6300 instead of 6200. At 5000
rpm, CHT’s cooled down to 200* and EGT’s were at 1000*.
| Quote: |
I feel the need to have my CHT’s in the 300-375 range. I’m also
reluctant to try smaller jets as I’ve been preached at to stay as close to
|
stock and the Rotax charts as possible. I have ordered new needles and
needle jets but the old ones look fine. Does anyone have a suggestion as to
how to get the CHT’s up or should I just fly the damn thing and quit
worrying about it!
Mike,
Your plugs indicate it is running rich.
You have not mentioned that you have dropped the needle to try and lean out
the mid range. I would try this and see what happens. I would not change
the main jet as you want to be able to drop the EGT with full throttle in
case the mid rpm range EGT's get too high. If dropping the needle one slot
change is too large, you can still move in the right direction by using
shims that will move the needle a quarter of a slot at one time. I used this
method on a 447 and continue to use it on my Victor 1+. I was running 1200
degrees F EGT's on the 447. How this can be done can be seen
at:
http://www.thirdshift.com/jack/firefly/firefly58.html
By running too rich overall, combustion temperature will go down and less
work can be obtainned. If your fuel is greater than 87 octane, change to 87
octane. It will increase the speed of combustion and produce more useable
work.
Always read your plugs until you have found the sweet spot. FWIW
Jack B. Hart FF004
Winchester, IN
| | - The Matronics Kolb-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?Kolb-List |
|
|
|
| Back to top |
|
 |
ropermike
Joined: 28 Aug 2006
Posts: 40
Location: West Texas, South Mississippi
|
| Posted: Fri Apr 24, 2009 9:56 am Post subject: Re: Kolb-List: 503 low CHT’s dilemma! |
|
|
Jack, thanks for the reply. My clip is already in the top slot. Even with the 150 main jets, my EGT's come down about 100 degrees when I go from full throttle to 5000 rpms. I'm burning fresh 87 octaine car gas.
| | - The Matronics Kolb-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?Kolb-List |
|
_________________
The next best thing to playing and winning is playing and losing!...Mike Hillger |
|
| Back to top |
|
|
lucien
Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM
|
| Posted: Fri Apr 24, 2009 11:14 am Post subject: Re: Kolb-List: 503 low CHT’s dilemma! |
|
|
| ropermike wrote: | | Jack, thanks for the reply. My clip is already in the top slot. Even with the 150 main jets, my EGT's come down about 100 degrees when I go from full throttle to 5000 rpms. I'm burning fresh 87 octaine car gas. |
Er, is the engine putting out full power? I just can't see how the CHT's can stay that low at 40 to 50 hp output, that's just physically impossible even if the OAT is 0F.
I flew my FS II on near years day here one year at it was 11F - I still managed about 280F CHT's at cruise rpm's of 5500.....
LS
| | - The Matronics Kolb-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?Kolb-List |
|
_________________
LS
Titan II SS |
|
| Back to top |
|
|
jbhart(at)onlyinternet.ne
Guest
|
| Posted: Fri Apr 24, 2009 4:48 pm Post subject: Kolb-List: 503 low CHT’s dilemma! |
|
|
At 10:56 AM 4/24/09 -0700, you wrote:
| Quote: |
Jack, thanks for the reply. My clip is already in the top slot.
|
In this case, you may want to change the needle jet one step smaller. It is
not expensive item.
Jack B. Hart FF004
Winchester, IN
| | - The Matronics Kolb-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?Kolb-List |
|
|
|
| Back to top |
|
|
ropermike
Joined: 28 Aug 2006
Posts: 40
Location: West Texas, South Mississippi
|
| Posted: Fri Apr 24, 2009 6:21 pm Post subject: Re: Kolb-List: 503 low CHT’s dilemma! |
|
|
I will order two in the morning. Thanks Jack.
| | - The Matronics Kolb-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?Kolb-List |
|
_________________
The next best thing to playing and winning is playing and losing!...Mike Hillger |
|
| 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
