[bshock]

Hi All,

I'm scheduled to launch on April 17, and when I made the drive to the boat this past weekend to test the batteries, the starting battery (Group 31 lead acid) showed 12.52 on the multimeter, which according to a chart I found online is 85% charged. The battery is only a year old, and was topped off before winter storage (indoor heated), and ALL the batteries were disconnected from everything. This is the only battery that has dropped significantly, albeit slowly, during the winter. The two 4D's are still showing more than 12.7 on the multimeter.

Is the Group 31 at 12.52 enough to start the engine (Westerbeke 30b3 diesel) in a couple weeks?

As always, thanks so much for any help!

 

[Markwesti]

My bet would be yes , it will be enough . We keep a emergency jump start battery on board , the type you can get from a auto parts store . We haven't had to use it yet though . Good luck and happy sailing season !

 

[MarkSF]

The Magic 8 ball says yes.

 

[PitApe]

That should be plenty. A Westerbeke 30b3 isn't a huge engine. I would think that even a 50% charge would be plenty, as long as there isn't something else wrong with the engine that makes it "hard starting". If worse come to worse you can always use that 4D bank get her started. Starting a little diesel with a deep-cycle bank won't hurt anything.

 

[bshock]

Cool, thanks all. I love that Magic 8 Ball too! Good idea about the jump starter. I forgot I had one of those, but will definitely be taking it along just in case.

 

[Maine Sail]

If that battery can't start a 30B3, even if it were at 11.9V, it is toast.....

 

[Bob142]

More than enough unless as mentioned there is another issue keeping the engine from starting thus needing a lot of cranking...the booster is practical just in case...after everything up and running you could check the cells to see if it was a equal discharge or one weak cell...

 

[MarkofSeaLife]

Yes u will be fine. But don't recharge your vibrator till the engine is going.

:laugher

 

[Minnewaska]

Are they flooded wet batteries (all common battery types are lead acid)? I'm betting the start battery is. That would seem to be normal self discharge. Next winter, I would stop by to top them off a couple of times. If they had been exposed to freezing temps, that might have been problematic. Better for the battery to stay more fully charged too.

Be sure to check acid levels and top with distilled water if low.

I also don't expect you'll have trouble firing her up.

 

[Delta-T]

You don't want to top off your batteries in the winter with water unless you are going to do a charge that will create a bubbling of the batt. acid. to mix it. Otherwise the water can freeze on the top. If the batts are fully charged in the fall and are disconnected, there will be no discharge. As Main Sail has drilled thru or heads now for many years.

 

[Maine Sail]

You don't want to top off your batteries in the winter with water unless you are going to do a charge that will create a bubbling of the batt. acid. to mix it. Otherwise the water can freeze on the top.

Excellent point !!! This point can not be emphasized enough!!

Once topped up with water batteries need a good "rolling" charge, usually well in excess of 14.6V in order to properly mix the electrolyte and prevent stratification of the electrolyte.

If the batts are fully charged in the fall and are disconnected, there will be no discharge. As Main Sail has drilled thru or heads now for many years.

I like to see all flooded batteries charged to "full" (14.6V - 14.8V to at least 1% of capacity in accepted charge current) then equalized before winter.

The odd battery out on this one could just be a bad/weak cell or the fact that it was not sufficiently charged in the fall, for a long enough duration or at too low a low voltage.

Also this was indoor heated storage where the battery self discharge will be higher that sitting outside and stored colder. Either way it should easily start the motor...

Hi All,

The battery is only a year old, and was topped off before winter storage (indoor heated), and ALL the batteries were disconnected from everything.

 

[bshock]

Thanks folks! I'll be sure to check the starting battery once we get into the slip. I really appreciate all the advise of the friendly people of the Sailnet think tank!

 

[Delta-T]

Although a battery may have a full charge, in real cold weather the amp output can be as low as half. I was taught by my old man that if a car won't start in the middle of the winter, cranking slow, and you know you have a good battery. Turn the headlights on for 30 sec to a minute, this will start a thermal reaction in the batt and create heat. Then the car will start. Point being, it will help to warm the batt up before putting it under a load. Warm day would be good. That goes for the engine and oil in the engine, when cold, it is harder to crank.

I assume this is a diesel, (I know very little about them)? When you turn the key to the run position before starting the engine, does that not start the glow plugs? Keeping the key in this position for 15 seconds before starting will heat up that batt giving you a better kick when cranking. Also, does the glow plugs draw the most power when starting a diesel? Diesels needing more power than a gas engine to start? And are diesels higher compression than gas engines? This being harder to start a diesel? Is there a compression release for a diesel? Can you some how create a compression release?

 

[Don L]

Yes u will be fine. But don't recharge your vibrator till the engine is going.

:laugher

Doesn't that depend on size, because size really does matter?

 

[jrcanoe]

And are diesels higher compression than gas engines? This being harder to start a diesel? Is there a compression release for a diesel? Can you some how create a compression release?

Yes diesels are higher compression and without spark plugs it is that compression that ignites the fuel air mixture.

 

[PitApe]

Yes diesels are higher compression and without spark plugs it is that compression that ignites the fuel air mixture.

Actually, it's the heat from that high compression, rather than the compression itself, that ignites the fuel-air mixture. The difference may seem a somewhat trivial point, but that is why the engine has to crank fairly fast, otherwise the heat will dissipate too quickly (in addition to the compression bleeding past the rings) and ignition temps can't be achieved. Of course, some diesels also have glow plugs to help the situation.

 

[nccouple]

Doesn't that depend on size, because size really does matter?

Always charge ours at the dock, while shore power is still connected.

 

[Don L]

Always charge ours at the dock, while shore power is still connected.

WOW, a vibrator that requires shorepower

 

[jrcanoe]

Actually, it's the heat from that high compression, rather than the compression itself, that ignites the fuel-air mixture. The difference may seem a somewhat trivial point, but that is why the engine has to crank fairly fast, otherwise the heat will dissipate too quickly (in addition to the compression bleeding past the rings) and ignition temps can't be achieved. Of course, some diesels also have glow plugs to help the situation.

Yes you are correct. I was just trying to point out that a compression release would be counter productive tactfully.