Auxiliary starting, what is the proper procedure?

[mitchellg2241]

I have a 2001 Monaco diplomat Cummins 330. When my starting batteries run low, wondering what the proper procedure is for using the auxiliary start switch, which is on the panel to start the engine using the house batteries. I read once you have to hold it down for at least two minutes but I'd like to know some opinions or processes.

 

Mitchell

2001 Monaco Diplomat 40'

[mitchellg2241]

53 minutes ago, mitchellg2241 said:

I have a 2001 Monaco diplomat Cummins 330. When my starting batteries run low, wondering what the proper procedure is for using the auxiliary start switch, which is on the panel to start the engine using the house batteries. I read once you have to hold it down for at least two minutes but I'd like to know some opinions or processes.

 

Mitchell

2001 Monaco Diplomat 40'

Also, should or can the generator be running?

 

Mitchell

2001 Monaco Diplomat 40'

[Tom Cherry]

Read your owners manual or download if you don’t have it.  Basically, the stock verbiage is that you hold “on” the boost for a certain period….then pause and repeat. The times and frequency and cycles “may” vary by model and year….so follow what was written for yours.

The INTENT is to put a quick surface charge on the Chassis….assuming that your House batteries are good or that you have 50A pedestal or Genny is running.  The caveat is that the  Chassis HAS to have or show some reserve or voltage or life.  If they ran down and are deader than the proverbial “door nail” while in storage, this will probably not work.  

SO, if they ran down over a few days while camping, you can probably use the protocols in the manual.  If they really got zapped and went south and you don’t see at least 12.0 VDC on your chassis gauge or using your VOM, it would be advisable to start the Genny….put a positive cable from the House to Chassis and let them charge for a few hours…..obviously if on 50 A, then let the jumper stay there and your inverter/charger should bring them back….assuming they aren’t toast.  If your House is down to 12.0 or so, it will take longer as they will split the charging amps.

I would caution about trying to use the boost if they were really shot.  An automotive jumper cable between the banks will, assuming the Chassis can be recharged is safer.  If you don’t get a good surface charge and have to pull 1200 Amps from the house and leave the boost on for too long, you run the risk of arcing and burning and pitting the boost solenoid contacts.  NOW…If your engine is running and the Genny will not crank, the boost will work.  BUT, if the House Is totally dead, there will not be any voltage to engage or power the boost.  Mr Jumper Cable Is always your friend and will keep you from damaging your boost.

That’s basically how it works…

 

[bobdinsmore]

My experience with a 2000 Diplomat  to try to start without the Boost, If that does not start on the first try (and what is my normal amount of time), then I push the Boost. I've never had it fail to start in this case. I don't wait after I push the Boost to push the starter.

[Gary 05 AMB DST]

18 hours ago, bobdinsmore said:

My experience with a 2000 Diplomat  to try to start without the Boost, If that does not start on the first try (and what is my normal amount of time), then I push the Boost. I've never had it fail to start in this case. I don't wait after I push the Boost to push the starter.

That's what I've done for years. The boost switch just closes the solenoid to connect the 2 sets of batteries together temporarily.

Gary 05 AMB DST

Edited March 24, 2023 by Gary 05 AMB DST
better explanation