Cranking issue

[Hdsechols]

Have a 2008 GulfStream front end Cummins 300hp diesel. Issue is that intermittently when I turn key the, dash lights up, then I wait for start engine lite to go out and I attempt to start engine, but battery appears dead. Obviously battery is not dead as dash lights up. After a couple of starting attempts, the engine cranks. I checked batteries an have 12.75 volts. Also just made it home from a trip with battery lite on and 10.9 to 11.9 volts showing on dash volt meter. MH would not start until I used emergency start feature. Any suggestions as to culprit. Thanks

[Biljol]

Do you hear the click when you try to start or just nothing.

What’s the voltage at the battery.

Two thought bad ignition switch. Or bad battery

[Hdsechols]

Connected to shore power last pm. Went out to check starting. Nothing happened when key turned. Nothing. Used emergency start function and my barely cranked. Volt meter showing 13.6 volts. Turned off, then attempted to restart. Everything worked perfectly. Showed 13.6 volts. Got to be a relay/switch/ solenoid. But where. Thanks

[clifford j]

BilJol asked an important question not answered,,, did you hear a click when you turned the key to start position. Reason for the question is to determine if the starting solenoid on the starter motor is pulling in and the contacts are intermittent. One condition mentioned was a slow cranking , that could also indicate a starter motor issue. An old time trick when a starter is suspect is to hold the key in the start position and have somebody wrack the starter with a hammer.

CLIFFORD

[Biljol]

So sounds like with the boost you did get it to crank some.

My guess is bad battery it will have 13.6 volts no load. Hit it with a load and the volts would go way down. The 13.6 is the surface charge of the battery’s but you have no cranking amps.

[Skip426]

Originally Posted by Hdsechols

Have a 2008 GulfStream front end Cummins 300hp diesel. Issue is that intermittently when I turn key the, dash lights up, then I wait for start engine lite to go out and I attempt to start engine, but battery appears dead. Obviously battery is not dead as dash lights up. After a couple of starting attempts, the engine cranks. I checked batteries an have 12.75 volts. Also just made it home from a trip with battery lite on and 10.9 to 11.9 volts showing on dash volt meter. MH would not start until I used emergency start feature. Any suggestions as to culprit. Thanks

Ok ; I'm seeing a bunch of stuff that has to be looked into .
Your dash lights DON'T require too much in the way of power; and your starter does .
Bad battery connections , can light up the dash but not supply enough power to start.
Same for a bad battery.
Low battery light and 10.9>11.9 volts on gauge is very troubling . With the engine running the alternator should put out 13 > 14.2 volts .
So if the battery connections are good and the battery load tests ok then alternator output needs to be tested too.

Once the connections , battery and alternator have tested good , then you can start looking for issues with the starter relay , starter solenoid , neutral safety switch etc.

[Hdsechols]

Originally Posted by Hdsechols

Have a 2008 GulfStream front end Cummins 300hp diesel. Issue is that intermittently when I turn key the, dash lights up, then I wait for start engine lite to go out and I attempt to start engine, but battery appears dead. Obviously battery is not dead as dash lights up. After a couple of starting attempts, the engine cranks. I checked batteries an have 12.75 volts. Also just made it home from a trip with battery lite on and 10.9 to 11.9 volts showing on dash volt meter. MH would not start until I used emergency start feature. Any suggestions as to culprit. Thanks

Thanks for all input on my issue. Found problem to be a corroded negative lead from the battery. Removed and cleaned. All works now. Will Load test battery.
Battery connection was tight and looked good but when I wiggled it with switch on, all dash lights came on as did solenoi etc. again thanks.