Need Help - Start Switch Prob

[MedicNovo]

My bus was running fine up until now.  It sat for about a month but when I went to start today the start switch was dead.  The batteries are full and have over 24volts.  Everything works but the start switch is dead.  It is acting like it is not in neutral, it is.  I tried the rear panel but the same problem.  Im not sure what else to look for with this problem.

PS supposed to leave this morning.

[JackConrad]

Try jumping right at the starter. Big positive post with cable from battery to the small terminal with the wire from the start circuit. If the batteries are up (Full batteries should be slightly over 25 volts)and there is no starter problem, the starter will spin. NOTICE: be prepared for a pretty good size spark when you make contact. I use a short length of 10 gauge or larger wire.
   Neutral start switches can fail.  would need to see your wiring schematic to trace out entire start wiring circuit.  what make & model bus?  Jack

[gumpy]

two things to check, in addition to what Jack said...

Make sure the front/rear switch on the engine compartment panel is set to front, or try starting from the rear panel.

Try bypassing the fuel pressure switch by jumping it to ground. I've had these fail. I keep an alligator clip next to it now and just
attach the wire side to ground.

[jjrbus]

BK got him going, it appears to be the starter relay!!!!

[cody]

Methinks BK whacked it with a hammer lol

[MedicNovo]

Sorry i took so long to reply.  As soon as I got it going I had to take off and just around to posting.  I jumped the solenoid and it started right up.  Many thanks to BK, who talked me thru diagnosing the problem.  BTW he is the man and recognised the problem right away.  Anyway, now i either have to fix my neutral safety switch or replace my starter relay.  I think Ill start with replacing the relay and then look to the safety switch (since I don't know where the neutral safety switch is on a MC-8).
Thanks guys.

[JackConrad]

The neutral safety switch is installed on the passenger side of the transmission.  There is also a neutral relay in the rear panel, along with the starter relay (and several other relays).  The neutral switch on the transmission provides the ground for the coil in the neutral relay.  Jack

[MedicNovo]

I replaced the neutral relay today, and it fired right up.   Thanks to all for the help!  Even got the relay for free from the local detroit diesel dealer.

[Busted Knuckle]

Good deal! Glad to hear that's all it was!   BK