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twinboat · 09-04-2018, 10:27 AM

The circled item is the charge and boost solenoid.

If you measure the volts on both big cables of it, with the boost switch held, they should be the same. If not its probably bad.

DunesView · 09-04-2018, 11:20 AM

Tom,

You said the 'circled item'. Did you mean to post an attachment?

For anyone else, 'the charge or boost' - is this the same as the 'aux start'? I'm not aware of a 'boost' button to hold like Tom suggested.

Thank you!

Beth

DunesView · 09-04-2018, 11:29 AM

So I just went out and tried to start the engine. It fired right up with almost only one crank. So even though my panel shows it at 12 most of the time, I am wondering if they are really holding a charge and the wiring is indeed the problem like Cummins said??? Just being hopeful.

So I also watched the volt gauge. Just under 12 like it's been. And 'Atl.Charge' light on. So I pressed the Aux Start and the volt gauge went right up over 12. So I am thinking, it was on the house batteries that are being charged either by the Xantrex/shore power or the Generator, right? So if I run the generator and press Alt Start, I will be running off the house batteries and should be able to drive up to Hudsonville, right?

If this is how it works, then I will feel safe in knowing this and making the drive up.

Beth

winniman · 09-04-2018, 11:47 AM

With your meter on your panels, you should be able to read what the battery voltages are. With the motor off and shore power off, read both banks of batteries. With a good charge they should be around 12.7 or so. Start the motor, and the see if they go up to around mid 13s to 14 volts. If they dont change from when the motor was off, the alternator is not working. Shut off the motor, and start the generator. Test the voltages again. The house batteries should be getting a charge around low 13s from the converter. The engine batteries may or may not be getting any charge from converter depending on your system. If the engine batteries are not getting any charge from having the generator on, or from the alternator, you will need to put a jumper on the batteries to keep you going to the repair shop. Its the same idea as holding the switch, just you dont have to push a switch for two hours. You will need to run the generator to charge the house batteries while you drive. Take a booster cable and jump from the house batteries to the engine batteries. This will keep them at a high enough charge to get where you are going for repair. Without the jumper, your engine will shut down once the voltage drops to around 10 volts. We had to do this last winter, as we blew an alternator, then had the new replacement go after only 800 miles. You can do these tests with a multimeter as well, but my old coach had the same display as yours, and I found reading the voltages on the display was accurate, and easier. Good luck. By the way, we replaced the Neece with a Delco for about 300 bucks.

twinboat · 09-04-2018, 11:48 AM

Sorry

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twinboat · 09-04-2018, 11:49 AM

Quote:

Originally Posted by DunesView

Tom,

You said the 'circled item'. Did you mean to post an attachment?

For anyone else, 'the charge or boost' - is this the same as the 'aux start'? I'm not aware of a 'boost' button to hold like Tom suggested.

Thank you!

Beth

Yes

vito.a · 09-04-2018, 09:37 PM

Quote:

Originally Posted by DunesView

If this is how it works, then I will feel safe in knowing this and making the drive up.
Beth

When I had this issue I used jumper cables from the house batteries to the engine chassis batteries and ran the generator.
If the house batteries are 6v golf cart batteries, just be careful how you connect the jumper cables. Connect the jumper cables to the same terminals your main battery cables are connected (the ones running to the inverter).

dix39 · 09-06-2018, 10:51 AM

We bought a '94 Dynasty a few weeks ago in Phoenix, AZ. On the way home the alternator failed. After trying a few other things I used jumpers to connect the chassis and coach batteries and ran the generator for the last 800 miles home. That worked for us and I would think it should work for you also, as others have said.

Following another thread earlier got me to thinking that one of the devices that charge the chassis batteries while using shore power or the gen. would work for this in a more permanent manner without having to add jumpers. A couple of these mentioned were Amp-L Start and Magnum Energy ME-SBC. Comments?

Best of luck with your problem and thanks for starting the thread, and to all who commented. I'm fighting a similar problem and it has been helpful to me as well.

Steve

DunesView · 09-07-2018, 05:25 AM

HI everyone,

My appointment for service is Monday. I've got the engine batteries charged up to 100%. I will not run anything else on the drive. I will take jumper cables along. And yesterday, a friend loaned me an extra set of deep cycle 12V's to take along. I've driven it over to Elkhart, which is about an hour and a quarter drive from here, to get this problem fixed originally at Cummins. Then when they 'couldn't fix it because it was in the OEM wiring', I drove it home again. Both times with the generator running. The voltage gauge did not move and stayed just below 12 all the way. So armed with all of your suggestions, I will set out. The drive up to Hudsonville from here is about 2 1/2 hours. I will post the fix afterwards!

Thank you!

Beth

YC1 · 09-07-2018, 06:16 AM

Twinboat showed you what to check.

You seem to have two problems. Your alternator should be charging the batteries but it is not. Your low 12 volts shows that.

Running the generator or shoreline uses the converter to put out the same charge as the alternator would. It connects to the house batteries but should also be (jumped) together via the solenoid/relay Twinboat circled.

It is very easy to test that thing. Put a voltmeter on the small connectors and see what shows while on shoreline, generator, or engine running. But NOT with engine and generator at the same time. That solenoid is not supposed to combine the banks when the generator and engine are both running. Hence, driving down the road with the generator running will not necessarily charge the engine batteries without holding the emergency start/aux start button pushed.

The emergency start/aux start button applies voltage to the Twinboat circled solenoid.

IF you get 12 volts or so across the small terminals the large terminals are virtually shorted together. This will then make the battery banks the same voltage and any charging source will be equally applied to the batteries.

However, that solenoid is a very common failure item. So much so that I carry a spare. That solenoid has been diagnosed on this forum hundreds of times over the years.

So it appears you have two problems. The alternator is not working correctly or its charge path is compromised. Then you have the issue of the battery combining system not functioning properly.

dix39 · 09-08-2018, 11:40 AM

For our jumpers we used a couple of 6ga wires attached securely + to + and - to - between the house and chassis batteries. I would be concerned about using clamp on jumper cables while moving down the road as they could come loose and create more havoc. I had clamp on jumper cables with me and did not use them for that reason.

When our voltage got down around 10-11 the transmission electronics stopped working. We were having that problem at the campground we had just entered. After I explained the situation the attendant got a couple of 6ga. wires for us and helped with the connections. That and running the gen. for 800 miles got us home.

I'm still fighting the original problem, and learning from this thread.

Steve

DunesView · 09-08-2018, 07:26 PM

I will be gone most of the day tomorrow, but will try to do some of the testing that Myron mentioned from Twinboat's post. You said test the small connectors on the relay. I don't think I was touching them to the right thing. I'll look at it when I get home tomorrow.

Thank you!

DunesView · 09-11-2018, 04:37 AM

Well, we made it up to Hudsonville yesterday. Without doing anything other than making sure the chassis batteries were fully charged, we made it over an hour into our drive. I stopped at a rest area, left it run while we ran inside. Back on the highway, it began to die. I pushed the AuxStart button and the house batteries took over! I ran the rest of the way with the house batteries in control, plus the generator running. So I'll post the fixes when the shop calls. Thanks again for all of your input and suggestions.

DunesView · 02-12-2019, 11:01 AM

HI all,

I have been gone for quite a while. In between all of the problems we have been working on on the motorhome, my husband got sick and passed away back in October.

So starting over here. I'd like to post the fix for our alternator problem. The alternator was bad. For those of you that read all of the different posts in this thread, Cummins had sent it out to be rebuilt. It was done fine, just re-installed improperly!!! Out of 4 wires, 2 were correct and 2 were switched. The shop in Hudsonville fixed this problem in minutes. The second problem we had with the air heater that Cummins said was a faulty OEM wire harness and they could not replace it - was a bad ground wire. Again, a quick fix for the shop in Hudsonville. Sad, sad, sad. So now that spring is on it's way, I will be hopefully able to get back on the road and build up some confidence that all is well with the motorhome! Sorry it took so long to post results, just had alot going here in the past few months.

Beth