spare battery to carry for yanmar 2gm20 starting

[UK-WOOZY]

im off on the boat this weekend. i want to bring a spare battery just incase the main engine battery fails for whatever reason, water ingress or whatever.
would this be enought to start the 2gm20?

300CCA
Hankook MF896 (U1MF-X) Lawn and Garden Battery

thank you

 

[fredrussell]

Why not buy a lithium jump start pack? They’re tiny these days and much easier to move around.

 

[Tranona]

Yes, but at the minimum so make sure it is fully charged. Assume you have one rather than buying one specifically for the job because for similar money you can buy a 45Ah car start battery with a higher CCA.

Do you not have a dedicated engine start battery and a means of paralelling to the house bank in the unlikely event the start battery is flat?

 

[UK-WOOZY]

Do you not have a dedicated engine start battery and a means of paralelling to the house bank in the unlikely event the start battery is flat?

I do, i have an engine battery and a leisure battery for the boat electricals. both wired into the Blue Sea Add a Battery relay kit.

was wanting to carry backup power lighter than another car battery.

 

[Tranona]

What else are you going to use it for? It is lighter because it is only 30Ah which is not a lot of use for starting anything other than a small engine and will not last long as services battery. Unless you have both batteries knackered can't see the need for a third. As soon as the engine starts you will have usable power from the alternator. The suggested start pack seems a lot more useful if your concern is that you can't start the engine with either of your on board batteries.

 

[colind3782]

Why not buy a lithium jump start pack? They’re tiny these days and much easier to move around.

Absolutely! I have one on the boat and one at home, no bigger than a large phone. The one on the boat started our Sole Mini 34 with no problems after six months on the hard.

Slim 20000mAh Car Jump Starter Engine Battery Charger Power Bank Portable # | eBay

 

[salar]

I use one of those jump start packs also. In fact I keep it in the car and take it to the boat when I go out. Just make sure it has enough grunt to turn your specific engine over.

 

[UK-WOOZY]

i do have a modern jumpstart in the car so will just bring that with, thank you all for the advice

hmm, how would i jump start with them, onto the starter motor terminals? OR like a car, onto the car battery terminals.

 

[Gixer]

I use a portable jump pack also as mentioned above. Used it many time to jump other peoples cars, charge phones/tablets even has a torch built in . I keep it in my car all the time, really useful.

 

[RogerJolly]

Be careful that the jump starter might not do dead flat batteries.

Eg there's a Halfords one that says it needs to see at least 3V.

Noco are saying it's 2V minimum, but there's an override option for dead flats.

 

[PaulRainbow]

i do have a modern jumpstart in the car so will just bring that with, thank you all for the advice

hmm, how would i jump start with them, onto the starter motor terminals? OR like a car, onto the car battery terminals.

Battery terminals. If they are really awkward to get to you could fit a pair of terminal posts in a convenient location.

 

[Macka1706]

What's wrong with the cranking Handle. They's all I ever used on my 2QM for around 30 yrs. Up to compression. Half a swing and away.
back in the '50's we used to swing the 60hp 2 strokes on the fishing boats. 3 men on piece of rope . Compression. Half a crank and away. Poof----Poof----Poof. for first 2 min's. Old 65/70ft Solid Pitch Pine and doing 7 or 8 knots.
Forward/Backwards on a variable prop. Winding like hell as they came up to the Fishing Wharf. I was 9 yrs on my first trip (mate's dads boat.) First pay on 11th Birthday.

 

[PaulRainbow]

What's wrong with the cranking Handle. They's all I ever used on my 2QM for around 30 yrs. Up to compression. Half a swing and away.
back in the '50's we used to swing the 60hp 2 strokes on the fishing boats. 3 men on piece of rope . Compression. Half a crank and away. Poof----Poof----Poof. for first 2 min's. Old 65/70ft Solid Pitch Pine and doing 7 or 8 knots.
Forward/Backwards on a variable prop. Winding like hell as they came up to the Fishing Wharf. I was 9 yrs on my first trip (mate's dads boat.) First pay on 11th Birthday.

My great grandad had a horse.............

 

[UK-WOOZY]

What's wrong with the cranking Handle. They's all I ever used on my 2QM for around 30 yrs. Up to compression. Half a swing and away.
back in the '50's we used to swing the 60hp 2 strokes on the fishing boats. 3 men on piece of rope . Compression. Half a crank and away. Poof----Poof----Poof. for first 2 min's. Old 65/70ft Solid Pitch Pine and doing 7 or 8 knots.
Forward/Backwards on a variable prop. Winding like hell as they came up to the Fishing Wharf. I was 9 yrs on my first trip (mate's dads boat.) First pay on 11th Birthday.

read its a good way to break the bones in the hand as the handle can snatch, i need my hands

 

[RupertW]

read its a good way to break the bones in the hand as the handle can snatch, i need my hands

My dad broke his wrist on one and although he sailed for another thirty years it was never without pain and never as strong. He used to compliment young waitresses on their strong wrists (to my teenage acute embarressment)

 

[Blueboatman]

What's wrong with the cranking Handle. They's all I ever used on my 2QM for around 30 yrs. Up to compression. Half a swing and away.
back in the '50's we used to swing the 60hp 2 strokes on the fishing boats. 3 men on piece of rope . Compression. Half a crank and away. Poof----Poof----Poof. for first 2 min's. Old 65/70ft Solid Pitch Pine and doing 7 or 8 knots.
Forward/Backwards on a variable prop. Winding like hell as they came up to the Fishing Wharf. I was 9 yrs on my first trip (mate's dads boat.) First pay on 11th Birthday.

I think you’re overcomplicating things ?

Just fit a mahoosive variable pitch propellor and bump start the engine under spinnaker

I always fancied having a non electrical, second, spring starter
( video here )
SureStart S30

 

[stuartwineberg]

Why not buy a lithium jump start pack? They’re tiny these days and much easier to move around.

Absolutely. I have a gooloo one and it kick starts my 2L diesel x trail no problem, get one rated for your size of engine. It doubles as a very useful phone charger and recharges itself from the cigar or USB socket on board while you are motoring.

 

[stuartwineberg]

Be careful that the jump starter might not do dead flat batteries.

Eg there's a Halfords one that says it needs to see at least 3V.

Noco are saying it's 2V minimum, but there's an override option for dead flats.

Mine has an override. It flashes if it can't sense a voltage, you press a button and it goes anyway but there are warnings about the fact you are bypassing some safety circuitry

 

[Macka1706]

I think you’re overcomplicating things ?

Just fit a mahoosive variable pitch propellor and bump start the engine under spinnaker

I always fancied having a non electrical, second, spring starter
( video here )
SureStart S30

"""I always fancied having a non electrical, second, spring starter"""

Hi.
On my 30ft fishing boat back in erly '60's. I had a new Ford engine from a site compressor. Then bought a new in box "recoil starter." Sold the electric one for more than Recoil cost me.
Wind handle till it clicks, Loading the spring. Hit the lever and it uncoils spring, Cranking the donk.
Magic things. I think I paid 15/20 UKpounds back then.
They were taken off new site Compressor for electric ones. around 6 from memory. I bought 3 sold 2. Nice profits.

 

[Iliade]

I have both an old fashioned lead acid car starter and a modern lithium one. The lead acid one never let me down until the battery inside started to deteriorate, after maybe ten years use, and it can be replaced. The lithium pack has failed to start my motorbike at least twice when the trickle charger(s) died and the battery discharged too deeply for the lithium starter to turn itself on. (Mine has no override that I'm aware of.)