two Constraints on one object problem

Support Animation and Rigging
#1

I am doing a beginner Blender tutorial I found here: http://gryllus.net/Blender/PDFTutorials/TheRocketSteamLocomotiveModeling.pdf

At the beginning of the tutorial, I am having trouble getting the connecting rod to have two constraints. One is a child constraint of the crank pin and the other is a locked track constraint to the linking pin. (The linking pin is a child to the piston rod.) Both constraints will work separately, but when I try to use them both, only the child to the crank pin constraint works. Does anyone know how I can get both constraints to work? I included three images below that will hopefully help illustrate my problem.

http://i1130.photobucket.com/albums/m539/Blanco111/Works%20in%20Progress/Locomotive1.jpg
Locomotive1.jpg1024×572

http://i1130.photobucket.com/albums/m539/Blanco111/Works%20in%20Progress/locomotive2.jpg
locomotive2.jpg1024×531

http://i1130.photobucket.com/albums/m539/Blanco111/Works%20in%20Progress/locomotive3.jpg
locomotive3.jpg1024×578

#2

I made quick wheel / piston model as it is described in the tutorial. And, it works fine. Check Connecting Rod constraints. There should be two constraints there; Child of with target set to Pin, and Lock Track with target set to Linking Pin.

Make sure origin location for each component is at the right place also. The origin of Pin and Connecting Rod is located at same coordinate in 3D space. I located Linking Pin and Piston rod at the same location as well. And those sets of points sit on a plane. Meaning, their Z and Y coordinate are the same. They are only separated by X distance.

When you animate, relationship between object origins are important. It affects your rig. You really need to nail it down. The tutorial seems little ambiguous about the placements. There are lots of parts you know.