Check the points

If the loco is stalling with any wheels on the points, check that the points are clean, no tiny grains of ballast interferring with mating up with the stock rail, and making good contact with the stock rail.  Diesels are often about the same length as the distance from the points to the frog, so what may at first appear to be a frog power issue can actually be a point power issue.

ballasting Atlas turnouts.

I believe the wet glue applied to secure the ballast has "wicked under the thin plates which electrically tie the points to the point rails and the outside rails.  Fix by adding a short jumper between each outside rail to the near point rail.  It happens every time I ballast Atlas turnouts.  Mr Fugate has covered this before and may have a sketch to clarify the wiring.

A tiny bit of oil is your friend

Before ballasting, I always use a couple of drops of an oil like 3 in 1 brand. A little at the point hinges and a little at the throwbar. An old trick that saves many headaches.

Thanks for this but as a

Thanks for this but as a novice I am not sure where you mean for placing the jumper. 

Hello Graham,The same

Hello Graham,

The same problem happened to me.

As stated by John: "the wet glue applied to secure the ballast has wicked under the thin plates which electrically tie the points to the point rails and the outside rails".

What I did to resolve this problem is to take a Q Tip dipped in alcohol and apply it to the metal plates situated underneath the mobile rail.

The alcohol diluted the glue and the now my locos don't stall on the turnouts anymore.

Hope this helps.

I've been ...

building layouts for 40 years....it never mattered how careful I was ballasting around turnouts, one - at least - always got screwed up. On my latest - and first HO - layout I used a different method. I use a very small brush and/or a blunt toothpick to carefully dab white glue around the points and head blocks, both inside and outside the rails. Time consuming - yes. but it can be done a few minutes at a time, one turnout at a time.  

Point jumpers

There are a number of different techniques for powering points.  My approach has been to solder jumpers across the gap at the heel of the point.

O scale Atlas turnout point jumpers:  https://rices-rails.blogspot.com/2011/04/point-jumpers.html

N scale Atlas turnout point jumpers:  https://rices-rails.blogspot.com/2015/01/point-jumpers-and-track-feeders.html

Lance Mindheim’s turnout tuneup for HO Microengineering turnouts (he solders to the bottom of the points which isn’t an option after you’ve laid track):  https://lancemindheim.com/about-us/me-turnouts/