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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Lowball on May 02, 2015, 03:06:26 PM

Title: 4104 wont stay running
Post by: Lowball on May 02, 2015, 03:06:26 PM
Hello all, I have been having some electrical/charging issues. My bus will start but runs rough and dies after a few minutes. My batteries have been dying and I suspect the alternator is not charging them. My next test will be to get a multimeter on the battery when it is running to check the voltage, but I am just wondering if there might be some other issues as well. Will the bus run with the alternator not outputting properly? Is there a fuel shutoff when the voltage is low?

Thank you!
Title: Re: 4104 wont stay running
Post by: Dave5Cs on May 02, 2015, 04:29:33 PM
I have started my engine and turned the batteries off and it stays running. No electrical needed on a mechanical diesel engine but you won't have any lights or signals so don't drive it anywhere. Is your air up and fast idle on because if it isn't and just idling the altenator will not start charging until it is. Watch your ammeter if you have one and when it is idling high enough you will see it move up to 24.6 volts or more unless you have a 12 volt system and then it would be 12 volts and hopefully 12.6 or higher. HTH
Dave5Cs
Title: Re: 4104 wont stay running
Post by: eagle19952 on May 02, 2015, 05:07:34 PM
hold a screw driver on the back center of the alternator...while running. if the alt is putting out it will be magnetic...substantially magnetized

next will be the how many volts... :-\
Title: Re: 4104 wont stay running
Post by: chessie4905 on May 03, 2015, 08:13:54 AM
 Check your fuel system. Make sure your fuel filters are full when you unscrew them if they aren't still canisters.
Title: Re: 4104 wont stay running
Post by: John Z on May 04, 2015, 07:28:15 AM
Check the fuel filters.
Title: Re: 4104 wont stay running
Post by: Jax DeBusk on May 04, 2015, 01:52:36 PM
When's the last time you changed the fuel filters? You could also have junk in your fuel line. Have you ran it with low fuel lately?

My 4106 recently had an issue like this, I ran it down below 1/4 of a tank, and pushed up a steep incline causing me to stall out on the Astoria-Megler Bridge, which was a terrifying experience. Was able to coast down to the bottom though. Had to end up blowing the junk out of the fuel lines on the side of the road with an air compressor and a generator.


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Title: Re: 4104 wont stay running
Post by: ridgeroadrunner on May 04, 2015, 05:53:11 PM
had the same problem with a 4104 with a stock engine 671 my problem was the trash in the bottom of the fuel canisters  , pout a full charge on you batteries so it will start easier. The alternators  will not charge until the air pressure is up on bus