RV won't start

[sf49erfan]

Hello again! Looking for some input on my 2006 Monaco Executive Matterhorn IV. We replaced the batteries in December. We have been parked at a campground since mid-January. I have occasionally cranked the coach and generator up. I have taken the coach out once to get it washed- get snow/dirt off. I cranked the engine up approx 3-4 weeks ago. Approx 2 weeks later, I tried to crank the engine and got nothing. Was out of town and just hooked up the battery charger to the batteries. When I try and crank the coach, it sounds like it is trying to start, the dash gauges register, start flashing and then the lights over passenger seat flash with the cranking of the coach. Coach doesn't start. The battery gauge is showing we have enough juice for the batteries to be working, but still can't get the coach to start. Any ideas/suggestions?



Thanks so much for reading and any input.

Tracey

[Dper041278]

There is a battery cut off by the passenger seat if it is turned off by accident the motorhome won't start but will turn over. Hop r this helps.

[Skip426]

Sounds like a bad/loose connection at the batteries , that connection could be bad enough to stop the charger working properly too.
Remember the gauge only needs mili-amps of power to show a reading, cranking the engine requires full amperage/ power to get the job done.

[RobRoy]

To start, you need to know is the battery state of charge ?

Hope this helps.

https://www.batterystuff.com/kb/arti...-basics.html#6

[RamiDav]

Sounds like weak batteries
Does the campground where you are have elect ?
When plugged in your coach should charge the starting batteries however
you can have problems with that system , so that they may not be charging .
If that is the case then every time you started and didn't run it for quite
a while to charge the batteries you may have been gradually discharging them .
Till you can sort things out a small battery charger hooked onto the start batteries
should get you going .
Having a charger on board is a good idea anyway .

Ray

[vito.a]

If I understand you correctly, the starter cranks the engine over but it does not run?


First, what engine is this? Cummins ISM, Cummins ISX, or Detroit Series 60?


Second, which batteries were replaced in December? The engine cranking batteries or the house batteries? The two large 4D batteries crank the engine over and the smaller 6v batteries (equipped either 4, or 8 with a residential fridge) run the house through the inverter.


Are you depressing the Batt Boost switch when cranking (upper left corner of the dash)? This ties in the house batteries to the engine start batteries. Also run the generator for a few hours to charge the batteries.


Try turning the ignition key to on and crank the engine for just a couple of seconds and then stop. Do this 3-4 times. This should insure the fuel is primed all the way to the injectors. Then try to start it. Make sure you let the starter cool down for several minutes in-between extended cranking periods.


The ISX is notoriously difficult to crank. Motorhomes use less amperage starting batteries than class 8 trucks because motorhomes have the house batteries to assist cranking.
Several owners have installed a newer style gear reduction starter that cranks the engine faster and starts it much better.


http://www.irv2.com/forums/f115/isx-...ue-196364.html


Hope this helps.

[sf49erfan]

@Ray- Yes the campground has elec. My husband had a portable battery charger hooked up for over 24 hours and it wasn't enough. We eventually hooked up our Dodge and was able to get it started.

Originally Posted by RamiDav

Sounds like weak batteries
Does the campground where you are have elect ?
When plugged in your coach should charge the starting batteries however
you can have problems with that system , so that they may not be charging .
If that is the case then every time you started and didn't run it for quite
a while to charge the batteries you may have been gradually discharging them .
Till you can sort things out a small battery charger hooked onto the start batteries
should get you going .
Having a charger on board is a good idea anyway .

Ray

[sf49erfan]

Originally Posted by vito.a

if i understand you correctly, the starter cranks the engine over but it does not run?---correct


first, what engine is this? Cummins ism, cummins isx, or detroit series 60?--yes, it is a 525 hp isx engine.


second, which batteries were replaced in december? The engine cranking batteries or the house batteries? The two large 4d batteries crank the engine over and the smaller 6v batteries (equipped either 4, or 8 with a residential fridge) run the house through the inverter. ---the 2 engine cranking batteries were replaced.


are you depressing the batt boost switch when cranking (upper left corner of the dash)? This ties in the house batteries to the engine start batteries. Also run the generator for a few hours to charge the batteries.---- i tried that once and it didn't help. I tried to run the generator and it shut off after approx 10 minutes, started again and ran for maybe a minute-did this twice and i didn't start it again.


Try turning the ignition key to on and crank the engine for just a couple of seconds and then stop. Do this 3-4 times. This should insure the fuel is primed all the way to the injectors. Then try to start it. Make sure you let the starter cool down for several minutes in-between extended cranking periods.


The isx is notoriously difficult to crank. Motorhomes use less amperage starting batteries than class 8 trucks because motorhomes have the house batteries to assist cranking.
Several owners have installed a newer style gear reduction starter that cranks the engine faster and starts it much better.


http://www.irv2.com/forums/f115/isx-...ue-196364.html


hope this helps.

thank you for the info!

[RobRoy]

So the failure was low voltage if I understand you correctly?

If so?... Why the low voltage?

Not being charged correctly?

Excessive parasitic current drain on the batteries?

Bad / weak Battries ?

Has the situation been corrected?

I see Vito linked to a starter replacement to help with cranking R.P.M.

You should be aware that low battery voltage to the starter motor for whatever reason causes very high current (amperage) loads on the starter motor and can severely shorten the starter motors service life.


Happy Trails

[oldguy70]

Was it freezing where you were parked. If batteries are low and it gets below freezing
they can freeze and that will wreck them. Being able to start your engine buy jumping the
batteries tells you that your batteries aren't doing their job. Take them back to where you got them and have them checked out.

[RamiDav]

If it started with a jumper cable boost , that narrows the problem down
considerably .
If the jumper cables were hooked to the batteries and not to the frame or
to the starter then it pretty much narrows it to the battery area ,
bad batteries or cable problems .
Cables can corrode inside the insulation in a manner where they look ok but will
become resistant with a heavy load .

I would take the batteries back and have them load tested .

Ray

[sf49erfan]

Thank you for the information. Unfortunately, I can't take the batteries back as I purchased them in Abilene, TX and now am residing in WA state. I will check the water level, try and charge her up and take her out this weekend.

Tracey

[RamiDav]

Taking the batteries back was a poor choice of words , taking the
coach to a battery place or a shop that can load test them is a better plan .
An Interstate battery store will check them and many parts stores like Auto Zone etc
can load test batteries but may not have a knowledgeable person to do the testing .

Are you experiencing the same starting problem as before the batteries were replaced ?

Have you checked to make sure they tightened all the battery connections
snugly when they replaced the batteries ?

Does any of the cables / connections feel warm / hot when starting ?

The advise has been really good by everyone but not knowing how knowledgeable
you are about mechanical and electrical things we don't know at what level
to suggest things .

Ray

[Outbound]

It is my understanding that your battery charger when plugged in to shore power will charge only house batteries, motor batteries are charged by alternator. I installed a separate unit to handle engine batteries.

Outbound
2002 Monaco Executive