BAC Forum

General Boards => Technical Support => Topic started by: George L Smith on November 05, 2018, 02:42:36 AM

Title: Engine won't start
Post by: George L Smith on November 05, 2018, 02:42:36 AM
I'm stumped.

The Alladin system shows 7.5 volts on the engine status. This seems right since the engine won't start. But, a volt meter on the chassis batteries shows about 11 volts. Clearly I have a problem, but not sure what it is.

Now the slides won't move either.

Not leaving until Tuesday, so I have tomorrow to figure this out. Or, I'm stuck at Lake Whitney RV Thousand Trails.

Any help would be appreciated.

George
Title: Re: Engine won't start
Post by: Gerald Farris on November 05, 2018, 04:04:21 AM
George,
Your chassis batteries are completely discharged, and if your inverter is charging your house batteries, your "BIRD" system is not working. If your inverter is charging your house batteries, you can take a jumper cable and connect the 12 positive terminal on the house batteries to the 12 volt positive terminal on the chassis batteries. This will allow your inverter to recharge your chassis batteries while it is also charging the house batteries. This is a temporary solution only until you can get the "BIRD" system fixed.

Gerald
Title: Re: Engine won't start
Post by: Joel Ashley on November 05, 2018, 04:10:28 AM
Can I assume your ‘07 has a Magnum inverter remote panel over the entry door, or elsewhere?

As a start, what does it’s screen read?  If plugged in to park power, are you sure you actually have power there, and that instead your inverter hasn’t been powering your 110v devices?  At 12 volts batteries are half discharged.  Sounds like the inverter charger hasn’t been working, thus the above questions.

Joel
Title: Re: Engine won't start
Post by: George L Smith on November 05, 2018, 04:22:46 AM
Thank you guys. I do have the MagnumSine Maximum. The house batteries are charging just fine. Its float charging as we speak. I am tied to shore power right now. I will jump the house batteries to the chassis batteries in the morning, and see what happens. Why would the Alladin say 7.5 while my volt meter says 10.5 or 11. Can't remember which.

What is the "BIRD" system?

I would have thought that the slides would be powered by the house batteries, but if not, then that would make perfect sense.
Title: Re: Engine won't start
Post by: George L Smith on November 05, 2018, 04:23:54 AM
I forgot to add that the house battery bank registers 12.65 volts on the same volt meter.
Title: Re: Engine won't start
Post by: George L Smith on November 05, 2018, 04:40:15 AM
I did research the "BIRD" system. Now, I have a new question. If the solenoid "Big Boy" was working properly, the battery "boost" should have connected the house batteries together with the chassis batteries, and the voltage on the Aladin should have shown the increase, correct? That not having happened tells me that that solenoid "Big Boy" is shot. Correct?
Title: Re: Engine won't start
Post by: George L Smith on November 05, 2018, 04:46:19 AM
Is this the one that I need?

https://www.amazon.com/TROMBETTA-TERMINAL-CONTINUOUS-114-1211-020-114-1211-010/dp/B013U62E6I/ref=sr_1_2_sspa?ie=UTF8&qid=1541393041&sr=8-2-spons&keywords=solenoid+trombetta&psc=1
Title: Re: Engine won't start
Post by: Steve Huber on November 05, 2018, 04:58:58 AM
George,
That's a possibility. There are a couple of things you can try though. First, measure the voltage on each of the large terminals on the Big Boy solenoid. If the  Bird is working and one set of batteries is charged, you should see the same voltage on both terminals, showing the batteries are tied together. If the voltage isn't the same, check the voltage at the BIRD controller. You should be seeing coach battery voltage at the "Coach Battery terminal, and if it is 13v or greater, the BIRD should be sending a voltage to the Big Boy to hold it closed. This will be 3 -4 volts on the Solenoid terminal of the BIRD. If this reads OK, the Big Boy solenoid may be acting up. The terminal can corrode if the sealing O ring fails. Try hitting the battery boost switch a number of times. That can cause the Big Boy to start making contact and working. Verify this by checking for similar voltage on the 2 Big Boy terminal lugs.
Steve
Title: Re: Engine won't start
Post by: Joel Ashley on November 05, 2018, 07:27:25 AM
Is this the one that I need?

https://www.amazon.com/TROMBETTA-TERMINAL-CONTINUOUS-114-1211-020-114-1211-010/dp/B013U62E6I/ref=sr_1_2_sspa?ie=UTF8&qid=1541393041&sr=8-2-spons&keywords=solenoid+trombetta&psc=1

I think a better match is an Intellitec like the 77-90006-120 (see Amazon).  But check the model number on your original, assuming it is factory.  Yeah, it ain’t cheap, but skimping on replacement parts for our grade of coach is not something that’s advisable, as many here have learned.  Also, not long ago there was a thread here regarding an owner rebuild of a Big Boy.   http://beaveramb.org/forum/index.php/topic,7961.msg55211.html#msg55211

 As Steve alludes, be sure your connections on the Bidirectional Isolator Relay Delay are solid, and also that wires to and from it haven’t been pinched in the door and damaged;  I have to carefully tuck the ones on mine in when shuttling it.

I’ve often thought that the slideout pump motor was house related as it is on many coaches, but there’s a ground buss bar point and a relay marked slideout in the chassis electrical bay, street side frontmost.  This of course implies the slides are dependent on your uncharged chassis batteries.

Joel
Title: Engine won't start
Post by: George L Smith on November 05, 2018, 05:16:44 PM
Thanks for helping guys. Everything works again. I jumped the house batteries to the chassis batteries as a temp solution, and allowed the shore power to charge the batteries. Although, I checked the battery voltage before I jumped, and the voltage was increased over what it was last night. Maybe the battery "boost" takes time to "boost" a dead battery.

Now I'm still not sure what I have though. I couldn't find a BIRD, though I did find the "Big Boy" in the rear run box. See attached pic.

http://beaveramb.org/forum/index.php?action=gallery;sa=myimages;u=34006 (http://beaveramb.org/forum/index.php?action=gallery;sa=myimages;u=34006)

Does it make sense that there is a "Big Boy" without the BIRD? I checked the voltage across the Big Boy. There is ~13.5 volts on each side of the relay, and something less than 3 volts across the two terminals. The Big Boy is not uncomfortably hot, but is quite warm to the touch.

Does this all make sense?

George
Title: Re: Engine won't start
Post by: Scott Shearer on November 05, 2018, 08:05:34 PM
George,

It looks like your Marquis has an Intellitec Battery Control Center (BCC). The BCC controls the Big Boy relay much the same way as a BIRD module would. It also controls the house 12 volt disconnect relays.

The image that you posted shows your BCC at the very right hand edge. It looks like the green 'ISO RLY ON' LED is illuminated indicating that the BCC is sending a signal to the Big Boy.

There are two yellow buttons on the BCC, one button will energize the Big Boy, the other will cycle the 12 volt house disconnect.

The IRV2 forum has a good write up on the BCC. Search for Intellitec Battery Control Center or Intellitec part number 74-00824-000.

Scott
Title: Re: Engine won't start
Post by: Steve Huber on November 05, 2018, 08:12:17 PM
George,
The Big Boy readings are correct. The 3V at the small terminals is the signal from the BIRD that keeps the Big Boy solenoid closed. Equal battery voltage on the large terminals indicates the Big Boy is closed and has tied the chassis and house batteries together for charging.
Not sure where the BIRD is located on your coach but it is probably not far from the Big Boy. The attached photo shows mine (black box) mounted to the rear elec bay door.

Oops, apparently Monaco decided to utilize different approaches in the same year coaches, depending on model.
 Thx Scott for clarifying.
Steve
Title: Re: Engine won't start
Post by: Scott Shearer on November 05, 2018, 10:17:06 PM
Here's an image of the Intellitec BCC.

Title: Re: Engine won't start
Post by: Joel Ashley on November 05, 2018, 10:32:39 PM
Thanks Scott... I didn’t know there was an alternative to the BIRD controller. 

Joel
Title: Re: Engine won't start
Post by: Lee Welbanks on November 06, 2018, 02:18:29 AM
I would be willing to bet money that the big terminals in the Big Boy are totally corroded, I've taken a few of these apart and cleaned the contact terminals and disk. One of mine actually tested good as far as voltage across, but very so corroded that it would not charge.
Title: Re: Engine won't start
Post by: Scott Shearer on November 06, 2018, 02:33:59 AM
I agree Lee, I've taken ours apart and cleaned it twice. Very corroded both times.
Title: Re: Engine won't start
Post by: George L Smith on November 19, 2018, 10:29:46 PM
So, it's been a while since I reported the final ( at least so far ) solution. Looks like both of my chassis batteries were toast. They are rated at 1050 cold cranking amps. Had them both bench tested, and they tested at 660 and 700 CCA at 12.7 volts. Don't know how old they were. No markings on the batteries. Big Boy seems fine. The button switch on the BCC switches the relay just fine.

I replaced them both, and have been monitoring the voltage for the last week or so. Voltage holding at 12.7 volts. And no problems cranking either the engine, or the generator. So far so good. Everything seems to be working.

Does anyone here think that I have only cured the symptoms, not the disease?
Title: Re: Engine won't start
Post by: Mike Shumack on November 19, 2018, 11:00:41 PM
12.7 V is a fully charged battery. You should wait about an hour after shutting engine or leave headlights on for a couple of minutes to remove the "surface charge" before taking the voltage reading to be accurate.  Be sure to start the engine and measure alternator output too. If you're getting in 13.5V range at batteries with engine running then, I'd say all is good.  Good luck.


Title: Re: Engine won't start
Post by: Steve Huber on November 20, 2018, 12:04:17 AM
George,
IMHO you've nailed the problem. If you are concerned about the Big Boy, randomly check the  voltage on its 2 large terminals. It should be the same if the coach batteries are ~13V. If not, the internal terminals may be corroded and need cleaning. I disassembled mine this year (~11 yrs of use) and found the internal parts to be pristine. If the O'ring is good, there should not be any moisture intrusion and resultant corrosion. If it does act up, using the Battery Boost switch can sometimes get it making contact again as it closes the contacts.
Steve