gr8flyer55

I am in the process of converting a ST 2500 to ignition and gas/oil mix. I will post a Walbro carb adapter drawing that I used on another large ST 3000 to replace the finicky glow carb. It is made from aluminum and uses a crankcase pulse to operate the Walbro pump. Only drilling one hole in the side of one of the beam mounts for a tygon fuel/pump pulse fitting. Vacationing in sunny Florida right now but when I get home Friday I'll scan the drawing and post it for you machinist types out there. It has necessary material removed for a clearance fit into the intake for cylinder fins etc.
Thinking of going with the 20% oil mix as a trial fuel with synthetic oil and a rimfire 1/4-32 plug. My other ST ran beautiful on this combo with timing @ 28 degrees. EI makes everything so easy it's a good choice for this fuel guzzler. Many plane options out there for this size engine. I have a Stinger 120 going together for my test bed. Should be a fun, light combination sport plane package for sure.

John

boisebiker

I am thursting for more information on these conversions but do understand how long back burner projects can take. I have a duramax that needs new injectors and it has been sitting for over a year waiting. Good thing I found a $500 beater to drive to work and back.

gr8flyer55

I'll try posting the picture of my carb adapter drawing..

John

boisebiker

Looking forward to your test runs on this setup. Thanks for the drawing. What carb did you use on 3000 and which will you use on the 2500?

gr8flyer55

Not sure on the 3000 but the 2500 is getting a homelite 25 cc carb, whatever number it is..seems the right size for the displacement. I had sold the 3000 with a plane..Biggest mistake I ever made..loved that engine..

By the way, Adrian (C&H Sparkguy) is reviving the CH ignitions and maybe the Synchro Spark modules..Been testing alot of things here that we make together, (ignitions & advance boards etc.) and it is looking like a go! Adrian is a great guy to deal with..wait till you see what will be available from his site. Website will be up shortly.

John

captinjohn

HEY...that sounds like good news.....Capt,n

nateprice215

My Feedback: (1)

Hey guys;

Ijust finished running my glow to E85 conversion today with great success; Ihave a super tigre 90 that Ijust ran with a glow plug (os #6).Iam running the weedeater 2 stroke synthetic oil @ 20%. It ran well without the glow plug igniter as well. The trick i used was getting my brother to machine down the head to a 10.5:1 compression ratio. It was a bugger getting started as the ratios of E85 were way off on the super tigre carb. Itached a 14x8 @ 8600rpm!! Ithink that is good, right? Thanks for the ideas you guys.

alshere

Wow, almost a 2 year old thread, a shame to let it die, so much valuable info. and the work done here was a great foundation. I began converting all my planes to E85 / glow fuel mix 2:1 with 10% bEnol on a glow plug, so far Im pretty impressed with the results. 1/8 turn on the air bleed and 6-7 clicks in on the mixture screw and she's singing. if any of the original folks that laid the foundation above are still around, I'd love some further input. how are your engines holding up? are you still running E-85? with glow at 26.00 a gallon this is an awesome alternative?

wingspan99

My Feedback: (2)

Wow, almost a 2 year old thread, a shame to let it die,

I made the original post on this thread and I have not flown my conversions more mainly because I moved to a high altitude in Colorado, over 6000ft MSL. My conversions were down in power a little compared to glow fuel at sea level, and it was much more difficult to tune them in the thin air here and they lost another 20% power due to the altitude, and so I didn't fly much for three years after moving here. During those three years the cost of LiPo's and electric power systems went way down and I converted most everything to electric. I also went with a large gas engine the DLE-55 and even an FPE 42cc. There have recently been a number of new small gas engines from Evolution in the .60 and .90 engine sizes at decent prices. There's been some ignition 4-strokes created as well, which was my last project, an ignition Saito 120 on E-85 which fouled the plug at idle a lot. -Tom

Tidnab

My Feedback: (51)

In your earlier posts you mentioned that E85 was 1.99 a gal. What was the price of regular automobile gas back then.I have never checked the price of E85 as there aren't any gas stations that sell it locally,but there are a couple about 45 miles from here. That's weird because there's an ethonol plant about 5 miles from my house.I have a car that will burn E85,but I never went to those places to try it ,if I was in that town,as I've been told that you get less gas milage with it.Also ethonol attracts moisture and I don't need a frozen gas line in the winter.I put dry gas into my tank at each fillup using the regular 10% ethonol gas.I started to use an additive called Star Tron that counteracts the ethonol and according to one of their techs, my gasline won't freeze up while using it.Plus I seem to be getting a little better gas milage with it in my tank. It only takes a little bit of it at each fillup so a bottle lasts a while.
http://mystarbrite.com/startron/

wingspan99

My Feedback: (2)

I doubt you'd need dry gas (methanol) in a fuel tank with 7-10% ethanol since the ethanol will absorb water easily. I'm guessing the Startron may be wetting the fuel, I have heard of people putting acetone into their cars, like 10oz per 15gal and got better gas mileage.

Tidnab

My Feedback: (51)

The ethanol doesn't absorb the water ,it draws moisture to it.Put about a cup of water in a clearish container and fill with one gallon of gas.Shake it up and let it sit for a while.The water is natually on the bottom of the tank, so the ethanol will go to it.Siphon out the liquid which is the water with the ethanol in it and you'll have pure gas.Some people do this to rid their r/c boat race fuel of ethanol.I've had my gas lines freeze up on my vehicle when I didn't use dry gas in the winter.The enzymes in Startron,counteract the ethanol and make it so it doesn't attract moisture and also doesn't corode older vehicles fuel systems.My 2009 HHR can burn E85 and it's fuel system is made to not corrode,but people say the poorer performance and lessened fuel milage makes it not worth using.Some guys that race or just play with r/c boats use camp fuel with their favorite oil mixed in instead of gasoilne.I've tried it and it works great and smells better,but the cost of the camp fuel is expensive.

Desertlakesflying

My Feedback: (28)

Why would anyone want to run ethanol. The power to fuel ratio sucks, and it reduces engine life span.

1QwkSport2.5r

Coleman camp fuel is primarily naphtha based and has a very low octane rating; somewhere around 75-85 IIRC. Fine for lower compression Zenoahs and the like, but anything with a compression ratio above 8.0:1 will have problems on it. Oil has a lower octane rating than the camp fuel so the mixed fuel has a lower rating yet.

Methanol is far better than ethanol for making power, but at the expense of burning 30% more of it. I don't believe ethanol has the same benefits as methanol other than it has a much higher octane rating than gasoline alone.

I have not had had fuel lines freeze in my trucks or my wife's car and we have lived in Minnesota all our lives. I used to use Heet™ Fuel additive but I never really needed to. The key with ethanol laced fuel is preventing phase separation. Easy ways to do that is add stuff like Sta-Bil Marine or not letting it set too long. When it absorbs a reasonable amount of water (as outlined with the add water and shake test mentioned earlier) it separates and then causes issues like was mentioned previously. Ethanol laced fuel is not a good way to rid us our dependence on foreign oil. It's a good way to increase repair shops profits IMHO!

alshere

well, this thread seems to be going off topic, I dont think were trying to solve the worlds energy problems, and no one is disputing the chemical properties of an alcohol base. I'm continuing this to not only lower the cost of my flying addiction, but also to attempt to see if it can be done effectively. so far I have 2 small test platforms, an OS 46 LA and an OS 60 running with a stable idle, good transition characteristic's. running head temp.'s 250-280 degrees and front bearing temp 170-180. Im also getting longer flight times. at a 2:1 ratio of 15% nitro and 20% mix of synthetic and castor oils. by my math, Im now paying just $9.79 a gallon for a 5% nitro mix.
On the down side, longer spin time with starter (especially cold) 5-7 seconds. Ive also found that abrupt transitions while inverted can cause a dead stick in the 46. but the 60 is no so susceptible. thats what I've got so far, weather permitting I'm going to fly my Enya R1.20 4 stroke this sunday on a similar mix with less oil.

wingspan99 nice to hear from you.

captinjohn

Let me/us know how the Enya 1.20 works out. I have one...never been run...new in box. Thanks, Capt,n

1QwkSport2.5r

I run my R120-4C on normal 5-10% nitro 20% castor glow fuel ($7-8/gal) and find it spits an obscene amount of oil from the breather. Last time I had the front housing off there was a teaspoon of oil in the crankcase. Less oil is needed for sure, I'm gonna drop down to about 14-16% oil for the R120 until I fit a Bowman ring into it. The factory ring has large ring gap that lets a lot of oil blow by. Do let us know how the R120 runs on this 2:1 mix. It's a real powerhouse on regular glow fuel.