Small pull engine w/Elec. Start - Want To Do away W/Battery

[kach22i]

I have a 1989 Scat II HP Hovercraft with electric start. Cyuna UL2-02 35 HP, two cylinder two stroke (like a Rotax).

The coil and the little black box (CDI?) never seem to last more than a season or two. I've gone through several in the 85 hours (over 15 years) I've had my craft.

The battery seems to die a lot, and taking it out and charging it is a waste of time and money to me.

I've operated the craft 85% of the time by pull starting, and I don't really need electric start.

How do I remove the battery and perhaps the starter without messing up the other electrical parts of the engine?

Can I just remove the battery and fly away? What do I do with the battery leads?

I don't operate at night, so I don't need the green and red bow lights to work.

I know to some of you these sound like silly questions. I would never run a car without a battery. However I've just come to the point where I'm looking to save some weight. The modifications I've done to my craft have all added weight. Added a fiberglass bottom to the ABS hull, insulated the thrust duct, added buoyancy foam, will install a heavy skirt material soon, and I weigh 40 lbs more than I used to.

While I'm at it, any tips for installing a new pull rope? The old one has seen better days, it's the original one.

[Joeaksa]

One thing that many people do not realize is that the generator/alternator do not power the vehicle, no matter what type of vehicle it is.

On almost every vehicle using a system like this, the battery is what powers everything, period. The alternator simply charges the battery back to where it should be.

Can you start some vehicles like this and drive them without a battery? Yes but not for long or often.

Might get a garden tractor or motorcycle battery to use in the thing. It would take care of the ignition and such and the generator would have something to work with.

JoeA

Pull rope? Good luck, with the spring involved it could be a handful!

[Jeff Higgins]

If there is some way to put a magneto on it you could run it that way. Otherwise, an ignition system with a coil needs a battery for the initial current before the generator or alternator spins up to supply current. I think it used to be called "battery-coil" ignition. I don't think you could spin it fast enough with the pull-start to generate enough current to get a spark. A magneto would though.

Maybe just get rid of the whole starting mechanism and put a very small battery on it? Without having to crank it over, it seems you could run a much smaller battery and keep the ignition wiring the same. I think...

[dhoward]

Well, not really.

You can run it without a battery if the alternator directly supplies power to the ignition. It may have to spin up to a certain speed before it will output enough to power the ignition, though. If it's a generator, less worries. You might want to research the type of alternator it has. Some will destroy the diodes if no battery is present. That's why I have a continous contact battery switch on by boat. When I switch from one bank to the other, it maintains contact at all times.
If you're replacing ignition systems and batteries often, have you checked the voltage regulator (if there is one)?

Geeze, Joe. Haven't you ever been so poor you only had one battery to share between two cars?