Cold Cranking.

[NickRobinson]

Depends on what "heavy duty" means. .

Indeed- When I rang round for battery prices when I was in the trade, often the seller would reply to my sharp intake of breath by saying 'It is a heavy duty one sir...'

So I would sometimes ask to be quoted for a 'light or normal duty' version, suitable for the vehicle specified.

The reply was always that there was no such thing (with a side order of 'we've got a right *&^%* here !)

Nick

 

[wotayottie]

I fitted a Red Flash 900 as a starter battery, very small and has sufficient CCA but its capacity is quite small, 13Ah. It will start the engine when fully charged, the engine starts first turn of the key anyway. I imagine that if the engine was at all reluctant the battery would not cope. It was an experiment that was not totally successful. Next time I will go for a battery about twice the size of the 900.

Interesting comment. My motivation is to be able to use the 300aH of leisure batteries that the boat has solely as a domestic bank and therefore increase endurance. But my concern about a small engine starter would be the heater plug consumption as well as the CCA to start.

In theory, a 5 second burst of a 1000watt starter motor should be something like 0.12 aH so a 13aH capacity should be more than enough. care to expand on your experience?

 

[Pete7]

Interesting comment. My motivation is to be able to use the 300aH of leisure batteries that the boat has solely as a domestic bank and therefore increase endurance. But my concern about a small engine starter would be the heater plug consumption as well as the CCA to start.

Like Vic we have a Redflash, (1100) but it doesn't work for us. The volvo 2003 turns over really well for 10 seconds then slows down but still turning. unfortunately the 2003 won't start in the first 10 seconds and the slower turning speed after this isn't enough to get it to fire, so end up switching in the house bank to give a bit of umph. I will revert to a big flooded battery when the Redflash is due replacement.

Pete

 

[Sniper]

Three years ago I bought a second-hand battery out of a diesel car from a scrap yard which had been drop tested. I think it cost me about £20. It has started my 1GM faultlessly ever since. However, I keep it fully charged and have a pair of 75ah 'leisure' batteries for domestic/navigation use. This way I think I have the right battery doing the right job at the right time (although with some flexibility in extremis)

 

[vyv_cox]

Similar to Pete7 I guess, but not the same. The Yanmar starts almost instantaneously every time. If the Red Flash voltage is 12.6 or more there is no problem. Our normal practice is to start the engine on the domestic bank, so the starter battery tends to be neglected somewhat. Our dual bank solar charging regulator should keep it topped up, but it doesn't due to some minor fault. The RF voltage gradually drops and when it reaches 12.4 it will not turn the engine over fast enough to start it. Just tried it, reading 12.3, and it would not turn the engine at all.

 

[ditchcrawler]

I also have a Red Flash 1100 starting a Volvo 2003 28HP.I have had no problems but I do make sure it is kept well charged.A cheap solar panel kept it around 12.7 over the winter.I have a voltmeter permanently attached on my electrical panel.