REFLECTOR: Injector Idle Mixture

[Andrew Ellzey]

Jerry,

I owned a M20E with an IO-360A1A for 13 years and have adjusted my mixture before. What the problem sounds like is that you have the Idle screw set to high to allow the mixture control to be effective. What I think you need to do is reduce your Idle to 600 or 700 RPM using the idle stop screw. This is a big screw that stops the travel of you throttle linkage. Before you do so you should return your star adjuster to as close to where you found it as you can. With the star adjuster as close to the original position then reduce the large idle stop to 600 RPM. At this speed you will be able to recognize any change that you now make on the star adjuster. When mine was adjusted correctly I could hear and feel an adjustment as small as one notch of movement. What you will need to do since you changed the adjustment on the star adjuster is to slowly adjust it in a direction that increases your RPM. Each time you get the RPM to increase with the star adjuster, you will need to reduce the idle stop screw to slow you engine again to 600 RPM. Continue to do this until you start to loose RPM from the star adjuster and then back off until you reach the highest rpm that can be achieved from the star adjuster only. At this point you need to adjust it one notch to the rich and then set the engine RPM with your idle stop screw for the RPM that you want for your Idle. A correctly running IO-360 should run very smooth around 700 rpm. You will now need to go fly your aircraft in order to clean your plugs. Watch your EGT and CHT when you take off and make sure they are in normal operating limits. You should also make sure that the check valve on your airbox drain is working correctly. To do this put your finger over the drain tube and your idle shouldn't change. If you feel a vacuum and you RPM increases you need to clean this check valve that is located in the 45 degree AN fitting.

Good Luck hope this helps,

Andy Ellzey


  ----- Original Message ----- 
  From: Brainard, Jerry 
  To: Velocity Aircraft Owners and Builders list 
  Sent: Tuesday, November 28, 2006 3:35 PM
  Subject: REFLECTOR: Injector Idle Mixture


  We are now doing some of the initial taxi testing and are having issues that appear to be mixture related.  I have tried to adjust the star wheel to lean the mixture, but I don't seem to be able to get there.  Maybe I'm confused by the manual (how likely is that?) so which way do you rotate that star adjuster (with the spring on the side) to lean the mixture?  We are only at 900' so that should not be a big problem.  I have rotated it until the wheel is almost to the bottom of the travel, and we still seem to have an over rich condition. 

  Any hints?

  - jerry
  Helping on 44VF 
  Almost flying




  CONFIDENTIALITY NOTICE: This e-mail message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information or otherwise be protected by law. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. 


------------------------------------------------------------------------------


  _______________________________________________
  To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector

  Visit the gallery!  www.tvbf.org/gallery
  user:pw   Check new archives: www.tvbf.org/pipermail
  Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.tvbf.org/mailman/private/reflector/attachments/20061128/4a62c98f/attachment.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 862 bytes
Desc: not available
Url : http://www.tvbf.org/mailman/private/reflector/attachments/20061128/4a62c98f/attachment.gif