Bill Killillay

My Feedback: (18)

Hello,

I won a Supertiger 3000 in an auction with a plane. What I really wanted was the plane and I got it, but now I have a Supertiger 3000 with no home. Can this motor be converted to burn gas? I would never dream of running glow, but I want to run gas. I've never converted a motor though so I have NO idea about the in's and out's and even IF it can be done.

Thanks in advance,
Bill K.

Bill Killillay

My Feedback: (18)

Here are a couple pictures of the motor that I have. I lifted these from the auction. I have the motor and it actually looks much cleaner and much less worn than in the pictures. One more question, IF it could/can be converted, would it put out enough power to carry around a 1/4 scale Patty Wagstaff Extra?

Thanks again,
BK

captinjohn

Why not glow? You can mix your own fuel and save $$$ in the long run. Read all the postings first .....use the search option. Good luck Capt,n

Antique

My Feedback: (4)

Gas 3000-- 18-8 MA prop, 8000 rpm
You could buy LOTS of glow fuel to make up the difference between the price of a gas conversion and the price of glow fuel...[8D]

SilverEagleBW

My Feedback: (1)

I thought you can run the large Supertigres without nitro.Methanol is around $2 to $3 a gallon and then mix around 16% Klotz KL 100 to it and go fly.That will save you some bucks on fuel.

w8ye

My Feedback: (16)

The oil/gas ratio in a Super Tiger has to be greater (more oil) than what you would run in a Zenoah or chainsaw engine.
This is because of the lack of needle bearings on the connecting rod. If the rod is modified for needle bearings, then the crank pin will wear out.

The Super Tiger carb as originally made will be almost impossible to set the mixture on when running gasoline.

With the extra oil needed with the engine conversion, A gallon of gas mix will cost you between $5 and $6.

Enjoy,

Jim

nicholas.t

My Feedback: (1)

the large super tiger engines will run on as low as 12% oil the fuel we use here is called big brute
and is 7% castor 5% synthetic and 88% methanol

captinjohn

w8ye: I think you can mix a gallon of GAS cheaper than $5-$6.

FenceMagnet

My Feedback: (2)

I have two that were converted with needle bearing inserted in the stock rods and the crank pin turned down and a hardened race pressed on.... small walbro carb with machined aluminum adapter.... CH Ignition..... runs GREAT with an 18-8 on 50:1 gasil on an original (heavy) UltraStik 120....

[:-]

Rupurt

FenceMagnet
Did you do the same on the small end?

Volfy

My Feedback: (23)

By the time you add up the cost of a Walbro carb, the carb adapter, needle bearing conversion parts, and the ignition system, you will have enough investment to buy a "real" gasser.

If your question is whether it is possible to do a gas conversion, then yes.

If you're asking whether it is economically feasible, then no.

Also, CH ignition used to sell parts for needle bearing conversion for the Big Cats, but they say the stock rod is not hardened enough to take the needle bearings. Maybe some of the older Tigres have hardened crankshaft. FWIW, I have a newer Chinese-made G2300 and the crankshaft show signs of heat-treating, whereas my older (but still recent manuf) Italian-made G2300 does not.

FenceMagnet

My Feedback: (2)

what you end up with is a reasonably light 30cc gasser that has more power and weighs less than a G-38, for instance.... besides, it's fun !!!

the piston end of the rod is okay the way it is.... if you keep the revs where they belong, less than 8000, the stock rod will hold up fine....

as for the crank pin, again, I installed a hardened race.... and the Italian made crank was hardened, just not hard enough to take the needles... I had to hit it with a torch to anneal it enough to cut it on the lathe.... I think the Italian made engines were heat treated (properly) in an inert atmosphere, so no tell-tale discoloration....

[:-]

Rupurt

FenceMagnet
How do you hold the crank shaft in the lathe?

FenceMagnet

My Feedback: (2)

made a jig from a chunk of 4" AL bar stock.... bored a hole for the crank journal so the pin is on center.... dowel pins keep it from turning.... a friend does his on a milling machine...

[:-]

Hobbsy

My Feedback: (102)

The easiest conversion would to Diesel, it would burn half as much fuel and turn a 24x8, 24x6 or a 22x8, which ever would give you scale like flight and sub 7,000 rpm.

Rupurt

Thanks I wonderd a bit about that. I have a moki 210 it has a hole down the center of the crank pin, which means it is to weak to turn down an press on a race like you did, I thought maybe I could turn it down a little and TIG weld some hard filler rod on then grind it to size, what do you think?

I don't neccesaraly wont to convert to gas but to be able to use a little less than 20% oil would be nice.

FenceMagnet

My Feedback: (2)

the inner races are pretty thin.... don't remember now how much, but it's worth checking...

[:-]

tkg

My Feedback: (1)

The Moki crank pin will break if you put a sleve on it and run it . You have to cut off the rod pin and then drill the crank and press in a solid hardened pin..... Several chances to ruin a good Moki crank.