Thread: October Ooops!
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Bruce in Bangkok[_16_] Bruce in Bangkok[_16_] is offline
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First recorded activity by BoatBanter: Aug 2009
Posts: 321
Default Starting issues inside October Ooops!

On Wed, 27 Oct 2010 07:13:45 -0400, "Flying Pig"
wrote:

Hiya,

Thanks for all the useful discussion, as well as some off-list comms.

Just a quickie before I dive into it with a pro today: I also measured the
resistance at the 1-2-all switch posts; the switch has no resistance issues
as questioned in one of the responses.

More later as I have something more conclusive...

L8R

Skip


One additional comment. From your post of the 26th:

Batteries floated for a while, left to rest for an hour (loads still
connected). 6.47 or 6.48 on all 4 6V, 12.8 on the start. Turned over
starter for voltage drop test, attachment points engine ground and starter
positive lug. 4V drop! Following the voltage drop tests, it wouldn't start
immediately; I quit after 5 seconds or so of cranking, cuz my experience is
that it will go in 1 or 2, tops.


However, Trojan recommends that for an accurate assessment of a
battery that it be fully charged and then "left idle" (no charging or
discharging) for at least 6 and preferable 24 hours.

They recommend completely disconnecting the battery; charging is less
then 70% of full charge; left idle for a time period and then the
voltage checked.

A fully charged battery will be 6.37/12.73 VDC
90% 6.31/12/62
80% 6.25/12.5
70% 6.19/12.37
60% 6.12/12.24
50% 6.05/12.10

However, these figures are predicated on the battery having
electrolyte with specific gravity of 1.277.

I find that often times, particularly in hot climates, the battery
sellers will use an electrolyte of slightly under the recommended S.G.
in compensation for what they believe will be higher then normal
operating temperatures.

In closing, your symptoms are exactly what my old pickup exhibits, low
cranking speed and what appears to be excessive voltage drop while
cranking.... In my case it is an old, wore out, battery that is due
replacement.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)