RV News RVBusiness 2021 Top 10 RVs of the Year, plus 56 additional debuts and must-see units → ×


Reply
 
Thread Tools Display Modes
Old 10-21-2020, 10:04 PM   #1
Junior Member
 
Join Date: Oct 2020
Posts: 8
Truck/Chassis alternator connected to generator? Sunseeker 2017

I'm wondering if the truck/chassis alternator is connected to the onboard Cummings Onan generator in any fashion? Sunseeker 2017 MBS 2400W.

I'm asking because I'm planning for some winter boondocking. In the event my AGM house batteries get too cold/weak to start the generator, will running the truck engine provide any juice to the generator? Thanks.
Eric Heffel is offline   Reply With Quote
Old 10-22-2020, 08:22 AM   #2
Senior Member
 
SeaDog's Avatar
 
Join Date: Jan 2016
Location: Idaho
Posts: 7,849
normally that is a serpent system the alternator charges the starting battery once the starting battery is full it may or may not charge the house batteries. The onboard generation charges the house batteries some rigs have an emergency start switch that connects the house batteries to the starting battery to start the engine.
__________________
Retired Navy
Jake my sidekick (yellow Lab) 10/04 - 05/20
2017 RAM 2500 CC 4X4 Cummins Diesel
2016 Flagstaff 26 FKWS
AF&AM & El Korah Shrine of Idaho
SeaDog is offline   Reply With Quote
Old 10-22-2020, 08:32 AM   #3
Senior Member
 
Join Date: May 2019
Posts: 1,276
You should have a momentary contact switch in the cab area that will temporarily connect the house and truck (MB Sprinter) batteries together. If your house batteries get too weak to start your generator, your truck battery can assist in starting the generator. You could also have the truck engine running when you hold the switch down and thereby use the truck alternator output to assist in starting the generator. Unfortunately, due to the location of the switches, this would be a two person operation.

Besides the above, the battery isolation manager should have a charge feature whereby the truck alternator will charge the house batteries if needed. That would be a slower process than the momentary switch, but would help you get the generator started.
__________________
2020 Sunseeker 2440DS Ford, Trekker cap, Topaz paint
BehindBars is offline   Reply With Quote
Old 10-22-2020, 02:24 PM   #4
Junior Member
 
Join Date: Oct 2020
Posts: 8
Momentary Contact Switch? I believe it may be above my pay grade to have access to such advanced intel.

If I had such a thing, I wouldn't know what to look for (what does it look like?). Or where (you say the cab area, but that could be anywhere like on the dash to under the floorboards near the battery). I'm attaching a photo of my chassis battery, which is located in the floorboards under the drivers feet. Does anything here resemble what you are referring to?

Thanks.
Attached Thumbnails
Click image for larger version

Name:	IMG_2597.jpg
Views:	15
Size:	405.2 KB
ID:	241707  
Eric Heffel is offline   Reply With Quote
Old 10-22-2020, 04:22 PM   #5
Senior Member
 
Join Date: May 2019
Posts: 1,276
Quote:
Originally Posted by Eric Heffel View Post
Momentary Contact Switch? I believe it may be above my pay grade to have access to such advanced intel.

If I had such a thing, I wouldn't know what to look for (what does it look like?). Or where (you say the cab area, but that could be anywhere like on the dash to under the floorboards near the battery). I'm attaching a photo of my chassis battery, which is located in the floorboards under the drivers feet. Does anything here resemble what you are referring to?

Thanks.
Sorry, I was wrong. I don’t know about 2017 models, but I consulted the latest 2020 Sunseeker brochure and I see that the emergency battery boost switch is standard equipment on the Ford E-450 and Transit, and the Chevy platforms, but is not included on the MBS chassis.
__________________
2020 Sunseeker 2440DS Ford, Trekker cap, Topaz paint
BehindBars is offline   Reply With Quote
Old 10-22-2020, 04:42 PM   #6
Junior Member
 
Join Date: Oct 2020
Posts: 8
Here is an email I received from Ryan at Forest River. Hopefully this can be helpful to others.

The only thing hooked up from the chassis to the generator is the fuel line. However the generator runs to charge the house batteries and when they are fully charged the solenoid will switch to the chassis battery to charge. The chassis when on will provide a charge to the house batteries to of course in case your house batteries die or to start the generator at the generator itself.
Eric Heffel is offline   Reply With Quote
Old 10-23-2020, 08:55 AM   #7
Senior Member
 
TowPro's Avatar
 
Join Date: Sep 2019
Posts: 821
I have a 2019 Forester built on a 2018 MBS, so my answer might be close.

I do not have the emergency push button battery connect switch, and was told MBS does not allow this to be added to coach.

But I do have a Battery Isolation Module under a cover in the entrance way steps. This BIM does have the capability to add this emergency switch but I don't think its necessary.

I had the same question about charging both ways so I called the manufacturer of the BIM.

Here is the logic on the BIM 160.

for MH engine to charge coach:
12v on IGN terminal.
Chassis battery must be above 13.3v.
Coach battery must be below 12.6v.
There is about a 20 second delay.
When the module connects power you will hear it click.
After 1 hour the BIM stops the charging and goes through this same voltage comparison above to see if further charging is necessary.

For Coach Charger to charge chassis battery:
Chassis battery must be above 13.3v
Coach battery must be below 12.6v.
when the module connects power you will hear it click.
After 1 hour the BIM stops the charging and goes through this same voltage comparison above to see if further charging is necessary.



I tested this with volt meter and doing things like turning MH headlights on with engine off to cause lower voltage on chassis battery and witnessed it switching both ways.
__________________
2019 Forest River Forester MBS 2401R
TowPro is offline   Reply With Quote
Old 10-23-2020, 10:33 PM   #8
Senior Member
 
Adrian Gordon's Avatar
 
Join Date: Mar 2018
Posts: 317
Quote:
Originally Posted by Eric Heffel View Post
I'm wondering if the truck/chassis alternator is connected to the onboard Cummings Onan generator in any fashion? Sunseeker 2017 MBS 2400W.

I'm asking because I'm planning for some winter boondocking. In the event my AGM house batteries get too cold/weak to start the generator, will running the truck engine provide any juice to the generator? Thanks.
First time I had my Leprechaun motorhome out 2.5 years ago it was pretty chilly at night and my furnace ran the junk dealer provider battery down so low that I could not start the generator in the morning. Our Leprechaun 210RS does not have the magic switch that enables you to connect the chassis battery to the house battery. Solution was to take a set of jumper cables and run from the chassis battery to the house battery, start the engine and jump start the generator from the chassis. Second step was to replace the original battery with two 12 volt, 85 AH Trojan batteries wired in parallel.
__________________
2018 Coachmen Leprachaun 210RS with DW, Nanuq the Samoyd puppy and the cat.
Adrian Gordon is offline   Reply With Quote
Reply

Tags
generator, sunseeker, truck

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.



All times are GMT -5. The time now is 12:40 AM.