Web tire can not connect to SM RTE when LB Servlet is running

Hello Experts , 

i have an impoant issue , regarding vertical scaling 

i'd like summrize it to you as bellow 

i added a LB servlet to SM.cfg , with 2 servelts , the Lb is running and i can connnect to LB Port on 13080 using widnows client installed on the SM APP RTE Server , 

but when i try to connect to LB Port using any client installed on another servers it can not conncect . 

however , i can connect to any of the servelts under the LB such as 13081 or 13083

what do you think ?

Envirement is as 

SM 9.52 P2 on windows Server 2012

SQL server 2012