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Topic: No battery Isolator on my '88 22' (Read 823 times) previous topic - next topic
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No battery Isolator on my '88 22'
Ive followed all the fat red wires in vicinity of the chassis battery and I found nothing. This is reinforced by the fact that a few months ago I left my parking lights on overnight(!!) and all batteries went dead. I charged the house batteries and the chassis battery came back to life also, so there is no isolator(or its both well-hidden and mal-functioning)Was this an afterthought to install an Isolator, or is mine unique? I have found  an Aftermarket VSR (Voltage Sensitive Relay) to install but I dont know where to interrupt the connection between House and Chassis batteries.  Any good ideas?
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette
Re: No battery Isolator on my '88 22'
Reply #1 –
Typically the isolator is mounted on the firewall inside the engine compartment. Your vintage should have a diode isolator, which will have a finned heat-sink and three or four connection terminals - standard from LD. If it was removed, look for the output wire from the alternator. That would have gone to the input of the isolator, with one output on to the chassis battery, and the other to a junction where the radio fuse, the cable forward from the coach batteries, and other accessories are connected.

Steve
2004 FL
2013 Honda Fit
Re: No battery Isolator on my '88 22'
Reply #2 –
Here is where mine was on an 85.

2000 Mid-Bath
2012 Lance 830 Truck Camper/2006 Cummins Dodge Ram Megacab
1985 Multi Plan - Donated to the American Breast Cancer Foundation.
Re: No battery Isolator on my '88 22'
Reply #3 –
Our 1983 LD had the isolator mounted above the starting battery.

.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: No battery Isolator on my '88 22'
Reply #4 –
Quote from: Larry W  - 
Our 1983 LD had the isolator mounted above the starting battery.
Interesting! My chassis battery is on the driver side
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette
Re: No battery Isolator on my '88 22'
Reply #5 –
Quote from: mrfixit454  - 
Here is where mine was on an 85.
Yours is easy to find, but nothing resembling that on mine . Mine has that same circuit breaker on the firewall behind battery...
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette
Re: No battery Isolator on my '88 22'
Reply #6 –
Quote from: Steve  - 
If it was removed, look for the output wire from the alternator. That would have gone to the input of the isolator, with one output on to the chassis battery, and the other to a junction where the radio fuse, the cable forward from the coach batteries, and other accessories are connected.

Steve
Thanks  Steve, I'll start from the alternator wire and go that direction
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette
Re: No battery Isolator on my '88 22'
Reply #7 –
Quote from: Dazed  - 
Interesting! My chassis battery is on the driver side

Our 83's starting battery was on the passenger side, with the coach battery on the driver's side,
LD mounted the isolators on both sides through the years, eventually sticking with the driver's side for both the isolator and the later battery relay.

Larry.
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: No battery Isolator on my '88 22'
Reply #8 –
Larry, is the 'relay' a booster to momentarily connect the house/chassis batteries for emergency starting? Mine does have a 'boost' switch either.
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette
Re: No battery Isolator on my '88 22'
Reply #9 –
Quote from: Dazed  - 
Larry, is the 'relay' a booster to momentarily connect the house/chassis batteries for emergency starting? Mine does have a 'boost' switch either.

In the mid-2000s, LD replaced the battery isolator with a relay, which connects the starting and coach batteries together when the alternator is generating.
LD never included a 'jumper', that uses the coach battery to start the engine if the starting battery is dead. If you have one, it was added by a previous owner.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: No battery Isolator on my '88 22'
Reply #10 –
I think Bob (Dazed) meant to say 'doesn't' instead of 'does'.   "Mine does have a 'boost' switch either".  
    Back in the day relays weren't always as reliable and the contacts would weld shut and leave you with a depleted chassis battery along with depleted house batteries.  The diode isolators (new tech at the time) are more reliable devices. At least they usually fail in the open condition, which still allows you to start the engine.
     Bob does need to trace the wiring and figure out exactly what he does have. Deep cycling the chassis battery isn't good for it, and you end up needing 'jump starts' too often.

 [My rig does have one now.  The heavy duty isolating relay I got for free from Kent when he had his solar conversion done, now resides near my battery box, and I can 'boost' the chassis battery from the lithium's with a push button near the dash should the need ever arise.]      RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: No battery Isolator on my '88 22'
Reply #11 –
Quote from: RonB  - 
I think Bob (Dazed) meant to say 'doesn't' instead of 'does'.   "Mine does have a 'boost' switch either".  
RonB you must be psychic 8)
Could you explain or draw a simple diagram of your relay and boost?
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette
Re: No battery Isolator on my '88 22'
Reply #12 –
Hi Bob (Dazed);  Situations that might discharge the chassis battery are leaving the headlights on too long, trying to start the engine too often in a 'no start' or not letting the engine run long enough to make up for the energy used to start it. Gas station lineups for instance, or something wrong with the alternator, etc.
   My #4 wire from the alternator to the battery box is now connected without a diode isolator. I replaced it with a 150Amp circuit breaker.  I have a 20Amp ($20) pwm solar controller repurposed to back feed (charge) the lead acid chassis battery, and run the stereo radio, GPS, TPMS CB radio and dash 'power points' including added USB charging ports.   That #4 cable at the battery box will feed my new isolator (still not hooked up) a 60/30 Amp DC to DC converter with a LiF battery charging profile. 
   That DC/DC converter needs a control wire from the engine, to only operate when the alternator is producing power (engine running).  I'm running a wire to do that now. I'm also running a wire coming from a momentary push button at the dash, to a surplus charging relay donated to me by another member here when his solar system was installed by AM solar.  Later model Lazy Daze stock relay:  https://www.supplyhouse.com/White-Rodgers-586-108111-Solenoid-SPNO-15-VDC-Isolated-Coil-Normally-Open-Continuous-Contact-Rating-200-Amps-Inrush-600-Amps?gclid=Cj0KCQiA0eOPBhCGARIsAFIwTs4gQws6LzxHDOujEFj9i1F0ccfuzbDUgO1hi70607__L02wturKK7kaAju_EALw_wcB    This relay is located at the Lithium batteries. They are protected by two 100A breakers (one for each battery) and their BMS's and the relay is good for 200 Amps (600A surge).  I'm adding this because it was free, and there is room at the battery box area. In addition I could use it to charge the LiF batteries from the alternator (engine running) in case something goes wrong with the fancy DC/DC Renogy converter. (I'd have to hold down that push button). Another possibility is if I need to 'wake up' the LIF batteries if they had shut down because of low charge status or cold temperatures. Or if the solar had shut down/ failure of the converter. Also to start the Onan generator if the LIF batteries were too low to do that. 
   Like LD, you could use this relay, to short your chassis and house batteries together while the engine is running to charge all of your compatible lead acid type batteries.
   Pictures of my setup in this regard wouldn't help you any, and I don't have them of my set up yet. Thanks for reminding me to get more busy with my camera.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: No battery Isolator on my '88 22'
Reply #13 –
Years ago, a marine battery switch was installed in our LD, along with a 2-gauge jumper cable running to the starter.
This allows shutting the coach battery on and off or jumpering the coach and starting the battery together when needed.
It sure beats using jumper cables.

Larry.
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: No battery Isolator on my '88 22'
Reply #14 –
Hi Larry;  I quit carrying my 20' #2 jumper cables. Too heavy and bulky.  I do carry a Li jump starter for the towed, which I rarely tow. The jump starter mostly is for other people at Caravan Club meetups. I do have a 50A Anderson plug paired red/black wire (with 50A circuit breaker) to give other people an assist on their house batteries or chassis battery.  As you know on a good sunny morning the LIF's shut off by 8-9 AM. Plenty to spare. The 13.6V is good to charge a depleted lead acid battery.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: No battery Isolator on my '88 22'
Reply #15 –
Quote from: RonB  - 
Hi Larry;  I quit carrying my 20' #2 jumper cables. Too heavy and bulky.  I do carry a Li jump starter for the toad

My heavy jumper cables have been hanging on the garage wall for many years, ever since reliable jumper packs became available.  A lithium booster is carried in the Jeep.
We also carry a 6-amp battery charger and extension cord for field charging.

Switching to the Blue Sky 3000i solar controller, with its ability to charge the starting battery has reduced how often we need to replace the battery and the need for jumpering.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: No battery Isolator on my '88 22'
Reply #16 –
Quote from: Larry W  - 
Years ago, a marine battery switch was installed in our LD, along with a 2-gauge jumper cable running to the starter.
This allows shutting the coach battery on and off or jumpering the coach and starting the battery together when needed.
It sure beats using jumper cables.

Larry.
That sounds like a simple solution. Where is the switch mounted?
I try not to break the rules but merely test their elasticity.  '88 22RL converted to Rear Dinette