lml@lancaironline.net Mailing List Archive

Tom:

I have a LNC2 with an IO-390 angle valve engine. Any right or left adjustments to the engine mount will be seen at the front end of the cowl such that the spinner may no longer be concentric with the cowling. Angle valve engines present a real fit challenge along the sides of the cowling. On my aircraft there is less than 1/2 inch clearance on both sides. The thrust axis of the engine needs to be within the limits in the builders manual otherwise you may introduce some unfriendly stall characteristics. If you are concerned about the ball being centered in cruise flight it would be better to affix a small bendable trim tab to the rudder to solve your yaw problem.

Regards,

Pete Field

LNC2, N775DX

90 hours, St. Louis

From: Tom McNerney [mailto:dudewanarace@yahoo.com]
Sent: Thursday, April 07, 2011 1:53 PM
To: lml@lancaironline.net
Subject: L-360 Engine Angle

I have a 360 with an angle valve motor. XP-400SRE 250 hours on this engine now. I would like to eliminate the amount of rudder required to keep the plane square. (ball in the cage) I have good reason to suspect the engine has been installed with too much yaw.

I have the engine level to the airframe in pitch. The manual calls for 1.5 degrees to the right in regards to yaw. (if I remember correctly) I assume this was built in to the engine mount.

In order for me to get the engine level at 0, and straight in yaw, it would take about a half inch of washers on lower right rubber engine mount, and one quarter inch of washers on the upper right mount.

Is this normal?

Tom