1980 MCI 9 Dashboard

[berrybus1]

Got me a new dashboard to install on my bus. This is what I am trying to do, I'm converting to a key ignition switch and need to rid myself of the Step switch and Master switch. If any of you guys have experience with retro-wiring a new dashboard, please let me know if I can call you and maybe you can talk me through it.  I can get bus ignition to start, but can't find wiring to shut it down....I have wiring diagrams from MCI, but not getting nowhere with them.  I'm on the last stretch of getting this bus done as this is the final interior upgrade, and this seems to be the ultimate stumbling block for me!

If any of you guys have experience with retro-wiring a new dashboard, please let me know if I can call you and maybe you can talk me through it.  I'm in trouble on this one. Help!

Jim

[Iceni John]

I ran into a similar situation when I was reconstituting my rear start panel after the previous owner had removed all its switches (don't ask me why . . .)   My bus's full electrical schematics showed how the rear stop switch should be wired, I did it that way, but it didn't stop the engine!   After much head scratching and the assistance of some folk here, I decided to ignore the schematic and do my own thing instead.   I ran a 50' length of 10AWG wire from the ignition solenoid in my front junction panel all the way back to my new rear stop switch, so now when I push in that switch it cuts the solenoid's ground and therefore stops the engine.   Simple, and it won't cause apoplexy to my DDEC because it's effectively the same as when I turn the ignition key off in the normal way.   Could you do something similar?   Any solenoid or relay will stop working when you kill the live or the ground -  it doesn't matter which.

John

[berrybus1]

We are replacing the dash and need a transmission temperature gauge sending unit on a ht 740 mci 9 located
Ignore this post, I started a new topic, just not sure how to completely delete a post


Sent from my iPad using Tapatalk

[bevans6]

First off, what is a "step switch".  My MCI doesn't have one of those.

Second, I would be pretty careful about just replacing the master switch with a simple key turn switch.  The master switch is a ganged four terminal switch that passes a lot of power to a lot of different things, and I would not simply replace it with a single key switch without thinking that through.  If all you want is to replace the start push button switch with a key switch, and leave the master switch, that is pretty easy, it's just an momentary on push switch.

Brian

[berrybus1]

Thanks for these comments guys, they have been very helpful!
Jim