OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines Using a Victa to power a 12 volt alternator

I'm thinking of making up a portable engine driven battery charger and thought a Victa engine would suit that sort of application but would replacing the cutter base plate with a V belt pulley provide enough flywheel inertia to enable it to start & run without any alternator load?

The alternative would be to use a 'proper' 1990's Briggs & Stratton Quantum or a horizontal shaft engine, but the Victa is very light compared to the other 4 strokes, which makes it a lot easier to cart around.

Hi LRT, no problems using a Victa, just would have to use the early full cranks so that you can turn the motor on its side and then using say a G3 carb rotate it so the carby stands vertically, don't think you could do it with a plastic carb because rotating the carb would require a manifold modification. As for flywheel weight you could use a heavy pulley for the belt or fit a heavy disc to the pulley. The alternative is to retain the blade carrier, minus the blades and make a belt cover to cover it and the belt

I tried this experiment years ago using a J A P 4 stroke and a 35 amp alternator ,It
was a wast of time the motor did not have enough power to run the alternator over the idle
speed.Now old alternators are 85 amp and up and yes you will need a flywheel or a heavy
cast iron pulley.Easier just buying a second hand generator for $40.

The Victa roller mowers (Victa Imperial was the name I think) of the 1970s had a 125 with modified G3 carbutettor, mounted with shaft horizontal. I think it was called a Victa power unit with red cowl instead of black and VC 160 style starter.
Were these ever used in other applications?

When I look up the specs,a little bit of conflicting information.

An alternator typically takes about 1 HP (horse power) for every 25 amps of power generated. So, a 100 amp alternator will require about 4 HP at full output. Most alternators do not operate at full output for very long.

The alternator can take up as much as 35hp.

Here is a 4 stroker, but I think he is dreaming a bit.
http://www.ebay.com.au/itm/Subaru-generator-12v-robin-4-stroke-/152610530571

Looks like 5 HP powering a 45 amp -60 amp alternator.

Another site had this information.
I simulated a test with a Summit one-wire, 100 ampere alternator and tested it at several RPMS. I loaded the alternator down with what I thought a fair representation of typical application of 65 DC amperes output at 13.65VDC. At 4500RPMs the alternator averaged over the 4 tests a measily 1.28 hp loss. It was really consistent with the high being 1.29 and the low 1.26 over the testing pulls.

These were the ones I was talking about,I see a couple are about $50 each,
sometimes they are only $20.

https://www.gumtree.com.au/s-850w+generator/k0

We only run a small battery bank to run a few lights at night as we are not on mains power. (The SEC want $70,000 just to connect.)

We use a 1963 and 1982 Lister diesel generators for the bigger electricity loads and running a 5kVa generator just to charge three deep cycle batteries isn't very efficient compared to an alternator or forklift battery charger.

I found this article which seems to have a lot of info:
https://www.homepower.com/sites/default/files/uploads/webextras/mark8.pdf

As long as the alternator can cool properly, the motor could be mounted vertically in a frame as on a lawn mower.

I've got a Honda E300 that just did the crank bearing but it only puts out 8 amps or so. It would take a week running 24 hours a day to charge the batteries unfortunately.

I do have one of these from a DC3, but it runs at 14,000 revs so would need some gearing up and a much bigger motor to run!

https://www.ebay.com.au/itm/321825898759

I was at a bloke place today and he had a number of old stationary engines that just plonk along and with their big flywheels run on the smell of an oily rag. One he started up and ran today was originally used on a generator. That aside, apart from the $70,000 for a fraction of that cost you can set up and go completely off the grid, so why would anybody go down the path of spending all that money so the power companies can go and rip you blind with their never ending price rises. You don't know how well off your are without having those mongrels getting in your back pocket

LRT I'm a little confused the thread started out that you were wanting a small portable genset, I assumed you wanted to use to charge up a battery on a machine you might be working on to now wanting to run the lighting in the house etc. Has to be a way somehow, how do your neighbours do it?

Yes the Lister diesels plod along at 1,500 rpm and last an awful lot longer than the modern diesels of half the cubic capacity as they are under stressed.

I've got my grandfathers c1910 Lister petrol J1 to restore at some stage and it is rated at 2HP @850 rpm.

Yes I'm wanting a portable 12 Volt DC battery charger
(Not a 240 Volt AC generator. The Listers run the power for the washing machine and the wool press. The battery inverter runs the lights at night to save fuel.)

I need to make up something to charge the batteries as we can't afford to put on solar at this stage. (We are not eligible for the solar rebates as we are not on the grid)

The neighbours near here are all big NZ owned dairy farms but there's at least 3-5 km from our place to a power pole.

Isn't it great in this day and age that places in Victoria (it is a well populated state and not very big) still has pockets that are not serviced by the power grid, but I guess the people of Garvoc don't rate too much on the grubberment radar

My suggestion on the use of a cheap generator is good for running a few different power tools
but not a good option for charging batteries to run a house off.It helps to have all the facts now.

That is a good document explaining the facts,a 35 amp alternator can be driven by a 3hp engine.
A 100 amp alternator needs at least a 5 hp engine.For alternators between 100 and 200 amps the
use of a 8 - 12 hp engine is recommended.

These figures I would say refer to a motor in peak running condition so if you use a old
second hand engine that is well worn you may need the use of a bigger worn engine to
get the horse power requirements.

Sorry I probably wasn't as clear as I should have been!

If I used a Victa, I'd definitely use one with a set of new rings but if I went the 4 stroke route I'd probably just buy a Chonda.

What horsepower does a Victa full crank 160cc theoretically produce?

Our battery bank is 550 amp hours so divided by 20 gives a C20 rate of 27.5 amps.

That means I only need a 3hp motor.

The HP specification was never included in the Victa 160 cc motor Manuals,I have
read that go kart enthusiasts say the Victa 125cc two stroke Lawn mower was designed
to cut grass at 3000rpm and gives 3hp. The old 125cc Victa mower ads say 3.6 HP.

The 160 cc Victa two stroke will be over the 3 HP mark that is required for the 35 amp
alternator.

And I have plenty of full cranks here if you need any to play LRT, only problem is that drive to Garvoc