Neu 1527/1y air version with holes.
 

This motor has holes in the front and in the back, directly into the wiring. I guess this is cause it's the air version, so it has no protection against dirt. But can I seal these up and not worry about heat buildup? And does anyone have any recommendations as to what I can use as a seal?

Mike makes a front endbell cover that will help. People also use foil tape.

http://www.rc-monster.com/proddetail...rontmotorcover

Aluminum tape is your friend !
I have several open endbell motors sealed up with the tape, dab some Shoe-Goo around the wires and your go to go !

I'm using some tape on my Neu 1515 .. never had a problem.

Yep, blue masking tape works for me too. I used gold stars from my daughters sticker book for a while also...each hole had a star!