I found the old wiring from the old engine. The wiring is the exact same thing coming off the new engine into the 6 pin connector so that white wire was not connected to the last engine. I have replaced seat and deck engagement switches. it runs fine and drives fine however as soon as the deck engagement lever is moved and the switch plunger pops out it stalls. I took great care not to disturb wiring during engine replacement. So the engine was plug and play according to both motor connections. 
 
New update: I disconnected the seat switch connector and I am able to start motor without seat switch connected. 

Yeah looking at the wiring diagram white wire goes from ignition s terminal to brake switch then blade switch then to starter solenoid. This gives the 12v to engage starter. Depending on how seat switch is wired it can start without it. Check normally open(NO) or normally closed(NC) switches. Does this have the reverse override button on it?

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Hi Mike,
I found the culprit and wanted to post my results. It turned out to be the cut off bar located within the seat switch plug. It was all corroded. Once removed with needle nose pliers it runs perfect. Thanks for all your help.
 
Jim

SRTsFZ6
Quote:
 
"it runs fine and drives fine however as soon as the deck engagement lever is moved and the switch plunger pops out it stalls. "
 
Perhaps zip tie the switch so the plunger does not pop out (by-passing it)?
 
 
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Glad you got it and thanks for update