hard start/ battery indicator needle bouncing

[Scalf77]

Have you had your alternator checked?

[jonyjoe101]

you might have a parasitic drain somewhere in your van. On my astrovan the battery will drain where it can't crank after sitting for 2 to 3 days.

Using a dc ampmeter I found the van is using about 300ma with everything turned off. (max allowable is 30ma)
I have to keep start battery charged with a dc-dc charger from my house battery 24/7. Its been working great so far. The start battery is an 11 year old agm and still cranking.

One source that I read could be draining the battery is the radio, even when off it suppose to use alot of power. I still havent checked it yet.

[boywonder]

One common parasitic draw is the CO detector......not a problem if van sits and you have solar. I think those are about 80ma.

[1der]

Originally Posted by boywonder

One common parasitic draw is the CO detector......not a problem if van sits and you have solar. I think those are about 80ma.

based on boywonder's 80 mA ----> .080 amps,
below is the reality check for the rest of us that think .080 amps is a small draw that can be ignored (spoiler NOT):

Per hour = .080 amps
Per day = 1.92 amps
Per week = 13.44 amps
Per month = 57.66 amps

Add in a few other parasitic and a 100 amp hour AGM is well below 50% in a month with no charging or driving. This is just the wired 12v CO detector.

Add solar (if the van gets sun exposure while parked) or a 3 amp trickle charger to the rig while sitting.

or pull the fuse for the CO sensor circuit while not used!

[doublevan2]

Maybe a parasitic charge hitting the batts !? - while it sets for even a couple of days ?

[REF]

How old is the house battery and have you tested that?
This is the scenario that had me chasing things when we first got our van……
The house battery was toasted and it was back draining the starters via the isolator being stuck in an open state due to the low house battery voltage.

[boywonder]

It's simple enough to determine if you have excessive current draw from your battery due to a parasitic load....

Disconnect either battery cable from the battery

Set your multimeter to current mode (you have to move the leads to current setting on the multimeter as well). Start on the 10A scale...if the current reads less than 1 amp switch to mA scale.

Place one meter lead on the battery terminal and the other on the disconnected battery cable and read the meter.

You are placing the current meter in line with the battery cable, completing the circuit; all the current into or out of the battery will flow through the meter.

If you have a clamp type ammeter.......even easier, just clamp it around either battery cable to take a reading.

[darkstar66]

Yes I have.

[darkstar66]

This is what I was wondering. May be onto something. Twice in the last six months or so I have had the batteries replaced. The only thing I can think of is the isolater going gunny. I have a 400 ah solar system with fairly new lithium so I do not think that has anything to do with the problem

[darkstar66]

Boy wonder. I will do that. Thanks