Today's Message Index:
----------------------
1. 10:29 AM - Re: 277 keeps falling off the pipe (Richard Pike)
2. 11:39 AM - Re: 277 keeps falling off the pipe (George Alexander)
3. 04:27 PM - Re: Re: 277 keeps falling off the pipe (Stuart Harner)
Message 1
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| Subject: | Re: 277 keeps falling off the pipe |
IT WORKS!
Over the last couple of weeks we tried taking 2" off the prop length; no improvement.
But a 60" prop is still plenty of prop for a 277, so no real harm done.
We were about ready to turn the 277 into a boat anchor, and then something stirred
way back in the memory banks - Back in 1983, I had a Maxair Hummer with a
277 on it, and when it was new, the engine ran properly with factory jetting.
After several months of flying and getting well broken in, it got wonky. Kind
of like this one.
Something we noticed on this engine, you could not get the EGT's above 950 under
load. If you went smaller on the needle jet, then it would not accept throttle.
If you lowered the jet needle lower than normal, it would not accept throttle.
The low and mid range was too lean.
So we took off the intake silencer, took everything back to stock jetting. No improvement.
The symptoms were constant: would not run normally between 5200 and
5800. It would run fast, or it would run slow, but not at a usable rpm.
So we decided to go bigger on the low end jets and and then see if it would accept
smaller top end jets. Bingo!
Stock jets are a 148 main, a 2.72 needle jet, an 8L2 jet needle in the middle #2
clip position, and a 45 idle jet.
Now running a 145 main jet, a 2.70 idle jet, an 8G2 jet needle with the clip in
the bottom #3 position, and a 50 idle jet. Set the Ivoprop so that it turns 5900
on climbout and it runs perfect, EGT stays about 1025, good throttle response.
Finally.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kolb Firefly Part 103 legal
Kingsport, TN 3TN0
Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489131#489131
Message 2
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| Subject: | Re: 277 keeps falling off the pipe |
Richard Pike wrote:
> IT WORKS!
>
> ...S ...N ...I ...P
>
> Finally.
Flaming enthusiasm, backed up by horse sense and persistence, is the quality that
most frequently makes for success. Dale Carnegie
--------
George Alexander
FS II R503
E-LSA N709FS
http://www.oh2fly.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489132#489132
Message 3
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| Subject: | Re: 277 keeps falling off the pipe |
Awesome troubleshoot and fix. Congratulations on a job well done.
Definitely one for the archives!
-----Original Message-----
From: owner-kolb-list-server@matronics.com
[mailto:owner-kolb-list-server@matronics.com] On Behalf Of Richard Pike
Sent: Wednesday, May 08, 2019 12:29 PM
Subject: Kolb-List: Re: 277 keeps falling off the pipe
--> <thegreybaron@charter.net>
IT WORKS!
Over the last couple of weeks we tried taking 2" off the prop length; no
improvement. But a 60" prop is still plenty of prop for a 277, so no real
harm done.
We were about ready to turn the 277 into a boat anchor, and then something
stirred way back in the memory banks - Back in 1983, I had a Maxair Hummer
with a 277 on it, and when it was new, the engine ran properly with factory
jetting. After several months of flying and getting well broken in, it got
wonky. Kind of like this one.
Something we noticed on this engine, you could not get the EGT's above 950
under load. If you went smaller on the needle jet, then it would not accept
throttle. If you lowered the jet needle lower than normal, it would not
accept throttle. The low and mid range was too lean.
So we took off the intake silencer, took everything back to stock jetting.
No improvement. The symptoms were constant: would not run normally between
5200 and 5800. It would run fast, or it would run slow, but not at a usable
rpm.
So we decided to go bigger on the low end jets and and then see if it would
accept smaller top end jets. Bingo!
Stock jets are a 148 main, a 2.72 needle jet, an 8L2 jet needle in the
middle #2 clip position, and a 45 idle jet.
Now running a 145 main jet, a 2.70 idle jet, an 8G2 jet needle with the clip
in the bottom #3 position, and a 50 idle jet. Set the Ivoprop so that it
turns 5900 on climbout and it runs perfect, EGT stays about 1025, good
throttle response.
Finally.
--------
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kolb Firefly Part 103 legal
Kingsport, TN 3TN0
Forgiving is tough, being forgiven is wonderful, and God's grace really is
amazing.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=489131#489131
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