Super - Ultra Capacitors For Engine Starting

[Photolomy]

Would a 12v starter start a DD 8V71TI? Sounds like it would from the description. Could replace 8 batteries with 2, and then set up a different 32v house bank. Wouldn't consider it till I needed to replace the 8v batteries, which is quite a ways off.

 

[krush]

Guy on here has 8v71n (which probably has higher compression) that starts with two 8d 12v batteries. One 8d might do it, but probably wouldn't get a lot of crank time.

 

[chuckbullett@gmail.com]

Besides using the Ultra Capacitor scheme to assist, does anyone here have experience using 16V Racing Batteries?

Our Hat has 32 Volt mains and I still have to replace the starboard bank beneath the Settee in the galley. I replaced Port last month with traditional 4D 8-Volt batteries which are getting harder to purchase in a high Ampacity version.

I have to do this soon... the 16 Volt batteries are high current, and about a third of the weight of the 4D's. Two, in series, will get the job done I think. The Interstate battery rep i was speaking with is really encouraging me to try this... and to his point, the 8Volt 4D's will not be made forever. Additionally, the starboard bank isn't used for house.

In their intended application, racing cars, they're typically not charged on the car, but our Hat has 32 Volt alternators.

Comments anyone???

Many Thanks

 

[DCMY #92]

Sorry for the delay in updating the capacitor installation. It's been finished and working great for several weeks. In order to use a smaller footprint than the old 8Ds I built an aluminum rack to stack the new group 31s (paralleled) one above the other. I also replaced all of the 55 year old 4/0 battery cables. KBI does not recommend a disconnect switch between the capacitor and starter. I was not comfortable with no disconnect on the battery, so I installed one of the existing ones between the batteries and the capacitor.
KBI provides a new DPST momentary starter switch with the intent that one pole will close the internal disconnect in the capacitor module and the other will simultaneously energize the starter using the original starter circuit. Since my boat used separate SPST momentary starter switches and I was using the momentary "start" position on the ignition key switches to activate my starting battery parallel relay, I rewired to use the existing switches to activate the starter and capacitor. I have to operate them simultaneously, but that has been no problem. It also gives me the option to crank only on the batteries occasionally to test their performance.
The capacitor takes several minutes to recharge fully, but it's not necessary to wait before starting the second engine. In fact, I discovered that the capacitor will start the 6V53 3 or 4 times with the battery disconnected.

So far I have no complaints with the system. The engines spin much faster when cranking and fire immediately. We'll see how they start cold when winter comes.

 

[zigzag930]

Very interesting idea and I will be following this for future updates. Would be nice to build a 32v version of this, which appears to be pretty straightforward.

The thought of not having to lug 120 lb batteries out of the boat brings a smile to my face. Even if soley used as a emergency starting bank, it would be a very nice setup - provided they are SAFE and work reliably.

 

[DCMY #92]

So far so good.