LT1000 new motor dies when put in gear

[natspawpaw]

Swapped blown motor (B&S 17.5 to B&S 18.0) on a craftsman LT1000. Motor runs good but only runs with clutch/brake depressed or locked. If I put it in any gear it dies. Also if I engage the blades it dies. Any suggestions? Electrical?

 

[Cusser]

If my LT1000 (I have a 2005 model), I would pull the drive belt (upper one) off a pulley, and start turning everything by hand. In fact, I did this today after mine stalled and wouldn't crank after mowing 100 yards. Everything was OK, put belt back on and mowed.

Question: do blades engage when in neutral/clutch pressed down?

 

[slomo]

So it runs all day long parked and dies only when you engage the blades? Sounds like a safety switch or similar. Or improper sequence of turning on the blades. Hopefully a real expert will chime in here and help you more.

slomo