Do I really need a separate starter battery

[Pitchondesign]

Originally Posted by Frankly

Those that carry a spare starter motor/ solenoid please raise your hand.





Frankly

I do. But it came with the boat and I never took it off.

[AndyEss]

Originally Posted by Frankly

Those that carry a spare starter motor/ solenoid please raise your hand.


Frankly

I do - now.

My starter failed while I was on a short cruise with a lovely, though somewhat unstable, young woman. The starter on my Pathfinder engine is in an almost inaccessible spot - and was likely original to the engine installation in the early 1980’s. My boat was then relatively new to me.
It took me two days to get that $&@$ starter out, and required me to cut off mount bolts with a Dremel type tool held at arms length to reach the bolt heads.

Whilst I was striving to get that starter out, my lovely crewmate drank all the liquor on my boat (not too much), got angry at me for requesting some help, and asked to be put ashore to hitch hike back into town (we weren’t far from La Paz). I didn’t have a spare starter, and myself had to hitch hike back and forth while the original starter was re-built.
Since then, I have bought a spare starter and know I can turn the starter mounting bolts.

Moral of the story - knowledge, redundancy, and not dating women 1/3 your age are good guidelines in owning a boat.

[Rucksta]

Originally Posted by Frankly

Those that carry a spare starter motor/ solenoid please raise your hand.

Frankly

Hand raised

[sailingharry]

I get the question -- from both sides.


My last boat had a Volvo MD11C, so fairly small (100A rated starter). My battery setup was A/B/Both (cause that's how it was built in 1979), but I used it as "Main" and "Emergency." "A" was a pair of Trojan GC batteries, and it did EVERYTHING. Start, house, the works. "B" was a Group 24 (??), charged by an ACR, and I used it once (I think) in 10 years. The point is that a single bank works very well.


My father's boat has a HUGE Perkins 4-236 diesel. His only bank is 4 GC's. Starts the engine, runs the inverter, runs the instruments, the works. With that arrangement, he has done the full length of the ICW 18 round trips, 3 trips to the Great Lakes, a Down East Circle, and a Great Loop. No problem. His "backup" is an installed generator with its own battery, which can feed the inverter/charger. He also carries jumper cables to cross connect the generator battery to the engine start. Not sure he has ever used the backups, but it would be pretty seamless. Point being, 4 Trojan CG's (so about 250 Ah of flooded LA) works very well without a start battery, even on a brute of an engine.


A pocket power pack would provide the appropriate backup, cost very little, take very little room -- and allow you to rescue a fellow boater in the anchorage.

[vpbarkley]

We have two banks. One bank is dirty. One bank is clean.

The dirty bank supports high amp, short duration loads. These loads include starters, bow thruster and windlass. This bank sees voltage variations as loads in excess of 100 amps are switched in and out. This bank is primarily charged by an alternator and is well suited to AGM batteries.

The clean bank supports low amp, long duration loads. This includes electronics, refrigeration, lighting and various water pumps. This bank provides relatively stable voltage for these loads. This bank is primarily charged by solar and is well suited to lithium batteries.

Either bank can stand in for the other in an emergency.

[guyrj33]

No, you do not need a separate starter battery if you can tolerate the increased risk of no being able to start your engine.

[Cheechako]

No you don't. Two banks is a great way to go instead IMO.

[nuku34]

My hand is up. I DO carry a spare starter with solenoid for my Bukh DV20. Starters do die and you might not find a replacement in the 3rd world.

[Frankly]

I have one also (spare starter motor).

Going fwd I am going to suggest my set up is a three separate starting bank configuration. One bank starts the engine, one bank starts the windlass, and one bank starts the autopilot. Just to keep everyone confused.


Frankly

[Shrew]

I have been sitting on my house battery for 2 years. I spent around 10-11 weeks between anchoring and moorings this summer. Every time I started my engine, it starts just fine.

1) I run the generator for 2-3 hours in the morning and 2-3 hours at night

2) I would still keep a starting battery just in case

[Dockhead]

Originally Posted by Frankly

Those that carry a spare starter motor/ solenoid please raise your hand.


Frankly

I have spare starters with solenoids for both main engine and generator.


Also spare alternators, fresh water pumps, sea water pumps, injection pipes, injectors, hoses, belts, lift pump, many other bits.


But my use case takes me sometimes months away from civilization, so, YMMV.

[Grattaway]

and no one has mentioned having a crank handle on board

[Bowdrie]

Originally Posted by Grattaway

and no one has mentioned having a crank handle on board

Interesting that you mention that.
A friend has a boat with an ancient Volvo 2cyl., and you can crank it, another guy has a single cylinder Sabb that you crank.

[Grattaway]

Lots of outboards use to have the ability to put a pull cord on a flywheel
And the likes of quad bikes and motorbikes still have pull or kick start often with decompression levers.
My Bukh DV20 has a crank but it would be a real witch to use - same as my old 1980's landcruiser - good for building biceps and wrecking wrists and sometimes starting vehicles.
I have seen old timers using a partly flat battery and a crank handle to start a truck when the battery wouldnt do it by itself

so sometimes an option but now I carry a starter pack because nostalgia only goes so far :-)

[Chris Cringle]

If, God forbid, you lose your house bank charge at about sunset, just as an onshore gale rolls in, you will have to wait until at least 1000 hours the next morning to begin to "wait a couple of hours for the solar panels to charge the batteries". Yeah, you can save about one cubic foot of space and a few feet of heavy wire, but......you bet your boat.