Is this a REAL Big Boy? Help with ID and Troubleshooting. Thanks.

[gjh2916]

On the high current plate their is a Battery Boost Solenoid I am pointing to it, and per attached drawing. Is this what everyone refers to a Big Boy solenoid? I'm having trouble keeping my chassis battery charged when plugged into shore power. I just replaced chassis battery and when plugged into shore power the chassis side of battery boost solenoid reads 12.78 volts, and the house side of solenoid reads 14.5 volts.

[Doug and Nicki]

See the following comments.  These guys obviously know their stuff.

Edited Sunday at 12:07 AM by Doug and Nicki
Clarification

[Tom Cherry]

Actually NO.  The ORIGINAL Battery Boost Solenoid was called something different…even Isolator.  Whatever is on your prints.

Later on when Monaco started using the INTELLITEC brand, they were called BIG BOYS….as that was the product name.

You do NOT have an Intellitec BIG BOY.  BUT you do have an older version by a different vendor.  But the control circuitry is totally different.  NOW THAT’s NOT CONFUSING?.?  LOL.

You have either a White Rodgers or a Trombetta solenoid.  I don’t know if they can be cleaned.  

The BIG BOY Solenoid in the 100 A size works off a continuous 12 VDC signal to the control wires (small terminals).  But, just to make it confusing, the 200 A, which is the mainstay and most commonly called BIG BOY is only rated for 15 - 30 seconds of FULL 12 VDC.  It will start to overheat the coil and burn it up.  There are specific control devices to reduce the control voltage to 8 or 4 VDC….then that puppy will stay happy.

Without having the print you have, I can, factually tell you this.  The solenoid IS supposed to be engaged and the internal high current contacts carry up to the rated level and it IS a a continuous duty…so the voltage to the control wires can stay on.

Two ways to test…do both.  Have someone hold down the BATT BOOST switch.  Don’t know without your circuit, which “system”, House or Chassis provides the control voltage.  Try it KEY OFF.  Check the small terminals.  Then KEY ON…test again.  Should be 12 VDC.  Finally…no joy.  Remove the one wire.  Do a continuity test to ground.  If NOT a ground….try the other.  ONE has go be ground.  What does the print say.  Once you have a good ground connected to a terminal…then any 12 VDC source should energize or lock (CLUNK) in the solenoid.

ONCE engaged….read the voltage to ground on each side.  Should be exactly, probably less than 0.1 VDC difference.  Then put the probes on the two studs.  ZERO Volts or less than 0.1 VDC. IF so….coil is good and contacts are good.  If coil is bad….need replacement.  If high resistwnce….such as more than 0.2-0.3 VDC difference or reading across the studs…bad contacts.

BUT if the coil works and the testing shows good contacts…and your boost works…now a matter of chasing the circuit.

BUT, most folks with rigs like yours and that big 3 stud device are replacing the whole system.  They are installing a Blue Seas ML-ACR.  Really inexpensive and you will or might spend more trying to put in “new” parts on a totally outdated system.

Use the search here.  Put in ML-ACR or ACR or Blue Seas….then click on everywhere.  Choose topics.  Skim.  Scads of topics and how to and info.  Do the search again….this time use files.  I think someone wrote up a paper on it,

EDIT….look in your manual.  Probably in section 9 Chassis electrical or maybe section 9.  There is usually a diagram or pictorial.

MY GUESS….from the connection points and trying to blow up the print….yes…that is the BATTERY BOOST Solenoid…trust me….but VERIFY yourself….

That’s it…good luck…let us know…

[Frank McElroy]

2 hours ago, gjh2916 said:

On the high current plate their is a Battery Boost Solenoid I am pointing to it, and per attached drawing. Is this what everyone refers to a Big Boy solenoid? I'm having trouble keeping my chassis battery charged when plugged into shore power. I just replaced chassis battery and when plugged into shore power the chassis side of battery boost solenoid reads 12.78 volts, and the house side of solenoid reads 14.5 volts.

You do not have a big boy in your model year coach.  You likely have a failed battery maintainer.  Here is a link to a set of wiring diagrams in our Downloads section.

 

[gjh2916]

Frank is there away to test the battery maintainer. the green light on it lit.

[Frank McElroy]

Measure the voltage to see if the House batteries while being charged is passing through to the chassis batteries.

[gjh2916]

I'm going to test my battery maintainer tomorrow, I found the testing procedure for Lambert LE-415. Also has anyone used a Xantrex Digal Echo Charge 82-0123-01 If my LE-415 is bad the two choices are the Echo Charge or Blue Seas ML-ACR. Looks like Echo Charge is easier installation.

[joefromperry]

15 minutes ago, gjh2916 said:

I'm going to test my battery maintainer tomorrow, I found the testing procedure for Lambert LE-415. Also has anyone used a Xantrex Digal Echo Charge 82-0123-01 If my LE-415 is bad the two choices are the Echo Charge or Blue Seas ML-ACR. Looks like Echo Charge is easier installation.

I used the Echo Charge in my 2003 Signature while I had my Big Boy out to clean / repair. It worked as it should, and I keep it connected, minus the fuse, in case I have Big Boy problems again.

[georgecederholm]

14 hours ago, gjh2916 said:

I'm going to test my battery maintainer tomorrow, I found the testing procedure for Lambert LE-415. Also has anyone used a Xantrex Digal Echo Charge 82-0123-01 If my LE-415 is bad the two choices are the Echo Charge or Blue Seas ML-ACR. Looks like Echo Charge is easier installation.

I installed a Xantrex “Digital echo-charge” in the front run bay when I added a dedicated starting battery for the generator. Working fine for the past 4 years.

[gjh2916]

My battery maintainer is defective that's why my chassis battery is not staying charged when plugged into shore power. I just had another thought other than the Blue Seas or Xantrex Echo. Buy a weatherproof NOCO 5amp smart charger, plug it into the duplex Block Heat outlet, unplug block heater which I never use. Then control the NOCO charger with Dash block heat switch. Anyone see any problems with this application.