I have a moki 2.10 and i wanted to know if there are any benefits when converting glow to spark ign.
I recently got a ch ign for my homelite and i was really impressed by the size and weight of the unit,
so i figure if the system could help with reliability or something(any excuse to get another one) that would be cool.

thanks Kevin

A good lick is to convert the engine but continue to use glow fuel with the ignition.

If you run gas, you will have to run more oil than normal.

Enjoy,

Jim

like Jim said you will still need lots of oil if going to gas and you will also lose power. you will also lose the cooling effect of methanol, many glow engines will overheat when run on gas.

best to stay with 0% nitro glow fuel. the big benefit will be that you are now in total control of ignition timing so a lean run will be less prone to causing deadly detonation. you might also gain a bit of power and have a lower reliable idle.


dave

Cool thanks.

Does any one have any experience changing the bushs for needle bearings to run lower oil

Now there's an interesting question I'd like to see answered. Also, has anyone converted a four-stroke model engine to gas? Why? Because Saito is about to release it's "220". A 36cc lightweight four-stroke. Wouldn't that be sweet on gas??!!

AV8TOR

Yes all BAD. The crank pin is not hard enough to run needle bearings on. The crank pin is hollow so if you turn it down to press a hardened sleeve on it breaks because its now to thin.
If you cut off the pin and machine the crank so you can press a a solid pin, the balance is off. MAYBE you could press in a hollow hardened pin but you would need a good machine shop to weld the pin and make sure it was STRAIGHT

Well, good points but I think any good machine shop could handle that part. But how would it be without oil in the crankcase? Would you still have problems because of that?? Without an oil control ring on the piston you couldn't run oil in the bottom end, and having to mix oil in the gas would defeat some of the purpose of the whole exercise. Just thinking out loud here; maybe just not feasible, but a nice dream...

AV8TOR

We're talking Moki here. A Saito 220 would be a whole new bag of worms.
ANYTHING is possible with enough $$$, look at the two model that have flown across the Atlantic. Both gas fuel 4c, an ENYA 155 and an OS 60. The Enya had a bushed rod with a dry sump oiling system, the OS just used $300 a gallon oil with a bushed rod. It only took 3-5 years to develop the engines.

What about machining it down and welding it oversize with something hard enough then machine to size

I have a Moki 2.1. That engine runs so good on 0% nitro fuel that I don't know why anyone would want to mess with it.

Mine runs well so far, I haven't built the plane yet so i have only run it on the bench. One of the reasons i was interested in converting it to spark is that the only way it seems to start is by flicking it backwards(so if you flick it forwards it runs backwards). With spark ign you are able to retard the timing on ign which would help with starting. The other reason is that the engine is going to be used on a scratch built sea fury and having a little more reliability would make me feel a whole bunch better and of course its fun to stuff around with things you probably shouldn't.

Kevin

I have several gas engines. The Moki is the most reliable engine I have. It idles so low that at times I have had to plug the exhaust pipe to get it to stop. It was sitting there ticking over at about 1200 RPM with the throttle closed as far as I could get it. I threw my handkerchief in it to stop it and it just threw it back at me and kept right on running.
Yes you have to flip it back wards to start it. Thats the beauty of it. Get enough fuel in it and one flick and its gone.

If you unscrew the throttle barrel stop screw a little it should stop easily when you close the throttle all the way. Just out of interest how did you run yours in? I am still in the process.

I ran four gal. of 20% castor oil/alcohol thru it on the bench just like the instructions call for. I coated the entire back yard of my daughters house with castor oil. She don't let me run engines there anymore. With that engine 4 gal don't take long.

Cool thats pretty much what i am doing except its the neighbors house getting oiled

Again it becomes to thin, the hard surface weld is to brittle and the pin will snap off.
The easiest way is just run gas with 10% oil and it will be OK. It will run hotter so proper baffling is needed. The Moki does not have a lot of fins like th3 big ST engines.
If you are running 20% oil now, running gas at 10% would reduce the oil on the plane to about 25% of what is there now. 20% vs 10% and fuel flow of 2oz per min(glow) vs 1oz per min (gas)
www.ch-ignitions.com has the conversion kits $170 for ignition and $80 for walbor carb and adapter.

Do you sell the walbro carbs i find it difficult to find them here in South Africa. The last one i got was built up from different second hand carbs from a lawn mower shop and its only 9.5mm and it cost close to 20 dollars

Hold on, I bought an ignition from you about a month ago and it was only $100 with a pulse switch and magnets. Does the one you mention have syncro spark?

The Moki kit has a syncro and a new prop hub, sensor, mount, magnet, switch and a 1/4x32 spark plug.
The cost of Walbro carbs just about doubled in the last 2 months, time will tell if we stay in the carb business.

Rupurt....What walbro carb do you want? I may be able to get you a used one for $5. What does it cost to ship one to your home town? You would have to pay shipping. Capt,n West Mich

tkg
I not really that interested in converting moki to gas but the electronic ing really appeals to me. Unfortunately i just blew all my cash on a world models extra 330 which will be the home for my moki for the time being. So I will probably order the ing next month thanks for your help

captinjohn.
thanks for your offer but unless you take credit cards it would be nearly impossible to pay you and still be worth while, In SA when you buy stuff from other countrys on a credit card only the government rips you off. When you make transfers the bank has a chance to rip you off to.(and they really know how)

Check out http://www.model-engine-sales.com/indexang.htm. They have web pages for m135B rc & m180B rc set up for ign. and gas carbs. the web page for the m210B rc is under construction. Might be a big savings on fuel being set up for gas. If it can convert my 210 I am going to consider doing it.

Glow engines run pretty hot when converted to gasoline operation, several years ago I bought a Merco .61 gasoline engine that had poor ignition system, Terry put a CH SynchroSpark on it and it runs very well now. When I first got it back from CH I tried to run gas with LawnBoy ashless oil mixed at 32 to 1. It would overheat and quit after about 30 seconds at full throttle. I finally came up with a cure by running the LawnBoy oil at 40 to 1 plus 4 OZ of castor. The taper on both needles in the carb are so slight they almost look straight.

Thanks oldtimer i hadnt seen that before, unfortunately they dont say if it has needle bearings on the crank if it doesnt it will have to be run on 10% oil like tkg says but if i does the maybe it could be a source of conrods and crankshafts which are needle bearing compatible.

Ok i just checked the instructions and they recomend 1:25 oil for breakin and 1:40 amsoil for genral running. Very interesting