Start problem after motor change

[Scritser]

Hello
I have a 1996 Thomas saf-t-liner with a cat 3116 and Allison mt643 that we have fully converted. We recently went thru a motor change out and since then, the bus won't start until I bypass everything and go to starter relay.

I believe it to be the neutral safety switch. I evidently didn't document this part of the tranny removal very well. How/where is the neutral safety switch and how does it wire in?

Also, when the bus is running (bypassing everything) after the pressure builds, the accelerator speeds up and continues to speeds that I fear would be dangerous, so I shut it down. What would cause the engine to automatically accelerate after the pressure builds?

Thanks!
Shawn and Sherri Critser

[Tootalltechie]

Google "allison mt645 neutral safety switch"


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[somewhereinusa]

Neutral switch is in the transmission. Hold the key to start position and move shift lever to see it it starts. If it does it's a simple adjustment. My Bluebird has a pinch bolt on the cable end. If it's similar, put shift lever in neutral, loosen the bolt, put put trans in neutral and retighten bolt.

Also, when the bus is running (bypassing everything) after the pressure builds, the accelerator speeds up and continues to speeds that I fear would be dangerous, so I shut it down. What would cause the engine to automatically accelerate after the pressure builds?

If it is you probably have some air lines crossed.