C7 no crank

[bruxus47]

C7 cat won't turn over . Chassis batteries ( new july 2014 interstate)at 13.0 V, house at 13.2V.Running 2 weeks ago just fine. Installed trickle charger across boost solenoid , cleaned all cables and now won't crank. All connections verified.Ignition fuses checked.Tank full, air filter changed 3 weeks ago.75,000 miles.start pressure at 80 psi ,idle at 40psi op. temp.Is the solenoid on the starter? Boost solenoid use , has no effect. I have rebuilt old English sport car eng. and transmissions, and have understanding on gas units.I know its something simple , , ,
Just spent days tearing out headbanger and bedroom cabinet , replaced with with 2 Samsung flats ,one smart. Installed new splendide WD2100xc.Looks good,, but can't start the kitty !!

please help

[jacwjames]

Do you see a voltage drop when you turn key??

I have a rear start selector switch in the back compartment with a separate start switch. This allows me to start the engine from the rear but if the switch is left in the rear position nothing happens when I turn the Key.

A couple years ago I had been doing a general inspection on my rig and accidently hit the rear start switch. A couple of days later when I tried to start nothing happen with the key, started pulling my hair out searching for the problem. Looked in the engine compartment and saw the switch had been hit.

Could this be your problem??

If not it could be a hung starter on the starter ring. Try hitting the starter with a wood block or rubber mallet.

[bruxus47]

I show no voltage drop ,and hear no solenoid clicking. I usually find issues where I have been working , and this time it was to install the trickle charger. I'll try the hitting the starter ( I remember doing this 40years ago !!) A screwdriver across the solenoid should tell me lots as well. Was trying to avoid crawling under. Maybe I have your switch and don't know it.LOL.
2005 Safari Cheetah cat C7 75,000 miles.

[SSRice]

I had a similar issue on my Detroit Series 60. I'd turn the key and nothing except tripping the starter relay breaker/ fuse.
I removed the wires from the solenoid on the starter cleaned , retightened and all was good. ✊✊🌳
But yes you have to crawl under.

[bruxus47]

I now have 13.6v chassis and 14.0V house , but I did notice a 1+V drop on my dash voltmeter, that I missed. Raining here today , but I have to beat this. Backyard mechanic pride and all .LOl. The trickle charger is performing beautifully , but I will disconnect, and try starter banging. thks to everyone so far . What does the 1 volt drop at key start mean ??

[Dupdyke]

Been out of kitty cats for a few years. On ISL 400 I am having issues and I found that if I start the onan first the cummins will start. I have been told it must be one of the bosch 87 relays in front run bay I will call monaco support one day this week and ask for help finding which one to try replacing

[Mike Canter]

There are also fuses in the Rear Run Box that if blown will cause it not to crank. The other thing to check is if the Allison Shift Pad lights up and works normally. If the shift pad is not on the Neutral Safety Start Interlock will not let the motor crank.


It would help if you told us what make and model your motorhome is

[bruxus47]

2005 Monaco Safari Cheetah 38PDQ.76K mi. Shift pad lights up . Pouring rain so reluctant to be working on electrical in rain . The right rear solenoid, I believe for the heater does kick in . Batteries still at 13.6 chassis and 14.0 house. The only thing I did , was to put in trickle charger and clean all cables and terminals. Almost 2.V drop on dash voltmeter at key start position. I have verified all connections tight to relays and fuses. Fuses for ignition system in left front bay are all ok .
No rain tomorrow I hope.

[Mike Canter]

First thing I would check when the rain stopped is for a blown fuse in the Rear Run Box. It should be labeled as Start or Ignition. Check them with a meter. You should also have Red, Yellow and Green LEDs back there next to thevStart fuse. With the ignition on look and see if you have a RED LED that is dark. Red indicates 12 volts coming out of the fuse. If dark means a fuse has blown. In your case the Yellow LED will come on when the ignition key is turned to crank indicating power to the coil on the relay and green LED comes on if the relay energizes and power comes out of the relay to the starter solenoid.

[bruxus47]

Well the rain stopped this AM:
Banged starter -nothing

Found rear run box ,tucked in top of bay above invertor.no LED's.
full voltage at solenoid , and heater.

Had wife turn key to start , solenoid pulled in , as well as the solenoid on starter. still nothing , ,which now looks like starter winding. All under connections are clean and tight.

Next move is to drop the heavy mesh steel guard , and verify by shorting across the solenoid. guess I'm pricing a starter. Still open to anyone ? THKs
to all so far.

[bruxus47]

PS: Had wife use booster button and heard starter solenoid even louder. still nothing, batteries still 13 +v.

PS2: totally DI'd ultra trickle start did nothing .

[Skip426]

Is the clicking you hear coming from the starter?
Did you see a name on the starter ? Denso ?
The solenoid on Denso starters has replaceable contacts.
If your starter solenoid looks like the photo , the cover comes off and the parts pictured , in the second photo can be installed.

[bruxus47]

starter has a full CAT number ,solenoid on starter has full cylindrical shape, I'll know better when cage is dropped. thks for info

[Pusherpilot]

Did you try whacking the starter when the key is held in the start position? I had an old Chevy PU that wouldn't crank every now and then and didn't respond to being whacked unless the key was in the start position. Really fickled.
Ron