 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
PSalter(at)aol.com
Guest
|
 Posted: Tue Jun 06, 2006 3:13 pm Post subject: CJ Engine Dieseling |
 |
|
I have had my engine continue to run roughly thru a couple of revolutions (not kick backwards) after the mags have been switched off. The engine has about 35 hours since major and the plugs are clean. I have been running a mix of Auto and 100LL but had the same problem with straight 100LL .
What can I do to stop the dieseling?
Phil
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
 |
dsavarese(at)elmore.rr.co
Guest
|
| Posted: Wed Jun 07, 2006 4:29 am Post subject: CJ Engine Dieseling |
|
|
Phil,
This condition can occur for a multitude of reasons:
- Built-up carbon in the ignition chamber can glow red after the engine is
off, providing a mechanism for sparking unburnt fuel. Such a thing can
happen when the engine runs very rich, depositing unspent fuel and particles
on the pistons and valves. Similarly, non-smooth metal regions within the
piston chamber can cause this same problem, for they can glow red. It has
also been suggested that an improperly rated sparkplug can retain heat and
cause the same problem.
- A carburetor that does not close entirely can contribute to running once
the engine is off, for the extra fuel and oxygen mixture can combust easily
in the warm piston chamber. Similarly, hot vaporized oil gases from the
engine crankcase and provide ample fuel for dieseling.
- Incorrect timing.
- An engine that runs too hot or too lean may produce an environment
conducive to allowing unspent fuel to combust.
- An idle speed that is too fast can leave the engine with too much angular
momentum upon shutdown, raising the chances that the engine can turnover and
combust more fuel and lock itself into a cycle of continuous running.
Here are a few links that may help in solving your problem. Personally, if
you haven't done so already, I would start adding MMO to the fuel at the
rate of 6 oz. per 15 gallons. Do it religiously and interpolate the amount
you need prior to fueling.
http://www.jeepster.org/swchapter/dieseling.html
http://www.cartalk.com/content/columns/Archive/1995/May/13.html
http://www.misterfixit.com/diesling.htm
Dennis
---
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
Desmor944(at)aol.com
Guest
|
| Posted: Wed Jun 07, 2006 8:09 pm Post subject: CJ Engine Dieseling |
|
|
In a message dated 6/6/2006 7:14:40 PM Eastern Daylight Time, PSalter(at)aol.com writes:
| Quote: | I have had my engine continue to run roughly thru a couple of revolutions (not kick backwards) after the mags have been switched off. The engine has about 35 hours since major and the plugs are clean. I have been running a mix of Auto and 100LL but had the same problem with straight 100LL .
What can I do to stop the dieseling?
|
Phil,
Dennis makes many good points, and Jerry may have nailed the answer.
Referring to the CJ Service & Maintenance Manual (Shutdown of the Engine, pg.203):
1. Set throttle for 700-800 rpm to cool the engine, and make cylinder head temperature not higher than 150 deg.C if ambient air is below 25 deg.C or not higher than 165 deg.C if ambient is above 25 deg.C.
2. Set throttle for 1,900 rpm for 10 - 15 seconds to burn off the plugs. "Then set the throttle in the position corresponding to 600 - 700 rpm, cut off the magneto switch, and set the throttle to fully opened position smoothly."
This technique will likely eliminate the tendency for the engine to run on, particularly with higher ambient temperatures.
Rich
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
wade154(at)frontiernet.ne
Guest
|
| Posted: Thu Jun 08, 2006 4:16 am Post subject: CJ Engine Dieseling |
|
|
Phil there are two things that come to my mind that I haven't seen mentioned #1 do you center your primer to the off position after start up? as the primer will dump fuel into the engine if not centered, next is it faulty after warm up just turn it to the cyl position if it runs ruff its probably working correctly. #2 have you had the auto-lean set as it seems your problem might be fuel related, the procedure is in the engine maintenance manual. Of course this is my experience with the Yak 52 the CJ is manual lean. And if you have a manual lean why don't you shut it down that way?
Good luck
Bill Wade
N4450Y
[quote] ---
| | - The Matronics Yak-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?Yak-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
