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Jump Starting 6V92 DDEC

August 25, 2018, 04:34:59 pm

Are there any special procedures for "jump starting" U300 with dual engine batteries? I ran mine down by inadvertantly leaving basement freezer running on DC. Choices, inter alia, are: 1. Jumpstart with truck, or; 2. Call Good Sam Roadside Assist.

Thanks!

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Re: Jump Starting 6V92 DDEC

Reply #1 – August 25, 2018, 04:49:01 pm

Just use your truck. Put the jumper cables on and let it sit and charge a bit. Also make sure you boost sw is off.

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Re: Jump Starting 6V92 DDEC

Reply #2 – August 25, 2018, 05:00:24 pm

As Bruce says, just connect jumpers, fast idle the car/truck for ten minutes and it will start right up. I had to do this as the PO mis wired the isolator and all batteries went dead the day after I bought it. If the jumpers are the $10 variety, it may take a few minutes longer.

Don't you have three engine batteries? I thought all Detroit 2 cycles do.

Pierce

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Re: Jump Starting 6V92 DDEC

Reply #3 – August 25, 2018, 05:18:47 pm

OK, Bruce, will do. Thanks!

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Re: Jump Starting 6V92 DDEC

Reply #4 – August 25, 2018, 05:20:57 pm

Pierce, Just two batts on mine. They look like big deep cycles, but I just discovered are 7 and 8 years old, respectively. They started her just fine until I drained them with DC fridge/freezer.

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Re: Jump Starting 6V92 DDEC

Reply #5 – August 25, 2018, 05:47:49 pm

Maybe your coach is different than ours. We have two 8D batteries on the street side near the rear tires for the house. There are three regular-size batteries in the engine area to start the Detroit. With the boost switch OFF they are completely separate. With the boost switch ON they are all in parallel. We can start the Detroit using only the engine-area batteries, and usually do so.

Suggestion: before you do anything else, clean ALL of the terminals and then tighten everything up.

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Re: Jump Starting 6V92 DDEC

Reply #6 – August 25, 2018, 06:46:38 pm

David,

He has the rear radiator model and I don't know where his batteries are. Yours and ours are close to the back bumper and right in the  middle. Yes, our original house batteries were in the same spot as yours.

Pierce

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Re: Jump Starting 6V92 DDEC

Reply #7 – August 25, 2018, 07:01:43 pm

It might be easier to boost the smaller generator and use it to charge the bigger engine start side.

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Re: Jump Starting 6V92 DDEC

Reply #8 – August 25, 2018, 07:08:33 pm

David, yes, engine batts are in the wet bay with house batts on this one.

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Re: Jump Starting 6V92 DDEC

Reply #9 – August 25, 2018, 07:10:09 pm

Toby, ordinarily it would be, but I'm grappling with a generator problem too, whereby no gen output.

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Re: Jump Starting 6V92 DDEC

Reply #10 – August 25, 2018, 07:12:39 pm

Also to all— After today's dead battery incident and jump starting, my Zantrex monitor panel only lights and shows data on the lower digital panel—no baterry charge or status indication. Does that panel need AC power? Would not think so, except for the generator- or shore power charging status.

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