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What to do with engine... New 1/4 scale piper cub

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What to do with engine... New 1/4 scale piper cub

Old 04-18-2016, 01:43 PM
  #26  
Truckracer
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When those ST engines were popular, quite a few guys just mixed a new gallon of 15% fuel with 3 quarts or so of Methanol to get the desired low oil mix. If you decide to run the engine, don't even try to use the ST glo plug if one is provided. I don't know of anybody that was very successful using those. I preferred a plug such as an Enya 3, OS A-3, OS-8. Some guys liked the OS F plug but I had better luck with the Enya 3. These engines also liked a traditional idle bar plug but avoid a FOX plug if you go this route. If you have a problem with this engine, it will probably be flame outs and of course they never happen at a convenient time.

Another point against those old big ST engines .... I always thought they were real shakers. Especially compared to most any engine available these days.
Old 04-18-2016, 04:46 PM
  #27  
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Originally Posted by fly24-7
Coleman fuel does not contain Ethanol. The Ethanol in the fuel tends to dry out the diaphragm in the carburetor, requiring an occasional carb rebuilds. Put a good quality 20-25cc gas engine in the Cub. Plenty of room for the ignition and additional battery. You'll have a reliable, no hassle set-up.
That was back in the 90's. all the engines of today have ethanol friendly diaphragms
Old 04-18-2016, 06:51 PM
  #28  
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Thanks for the info. I'm lucky enough to still be able to get ethanol free premium fuel around here. Probably not for long tho.
Old 04-18-2016, 06:57 PM
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Thanks for the info. I have an osF plug brand new laying around. I'm looking into a gas engine now for the cub for sure. But A post earlier said I would probably only get 50$ if any offers at all on the big cat. By time I ship it, it's not even worth my time. I will probably just keep it and run it on a test stand and see if I can work on my tuning skills. I have a super Tigre .75 in an extra 300 I flew tonight. Finally getting it dialed in. I thought about mixing some Methanol with my 15% nitro 18% oil wildcat fuel. But I'm not having any luck finding it locally. If I could find it locally and mix it will my current flow fuel I would run the big cat for awhile. It would definitely bring the cost down. If you guys have any ideas on where to get it that would be great.

Last edited by Dan33klein; 04-19-2016 at 06:37 AM.
Old 04-19-2016, 08:20 AM
  #30  
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Coleman fuel can damage your engine due to the low octane. Regular gas with some fuel additive works fine.
Old 04-23-2016, 12:23 PM
  #31  
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PM sent!

Originally Posted by Dan33klein
Thanks for the info. I have an osF plug brand new laying around. I'm looking into a gas engine now for the cub for sure. But A post earlier said I would probably only get 50$ if any offers at all on the big cat. By time I ship it, it's not even worth my time. I will probably just keep it and run it on a test stand and see if I can work on my tuning skills. I have a super Tigre .75 in an extra 300 I flew tonight. Finally getting it dialed in. I thought about mixing some Methanol with my 15% nitro 18% oil wildcat fuel. But I'm not having any luck finding it locally. If I could find it locally and mix it will my current flow fuel I would run the big cat for awhile. It would definitely bring the cost down. If you guys have any ideas on where to get it that would be great.
Old 04-24-2016, 04:34 AM
  #32  
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i think the fuel conditioner HEAT in the yellow bottle is methanol
Old 04-24-2016, 04:37 AM
  #33  
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id say 135.00 with the pitts
Old 04-24-2016, 05:33 AM
  #34  
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Originally Posted by raptureboy
Coleman fuel can damage your engine due to the low octane. Regular gas with some fuel additive works fine.
Relevance of octane is highly overrated for the engines we are using. Colemans works fine in my Zenoah, your results may vary. Do a search for it on the net. you will find many satisfied users.
The naysayers likely have not tried it or just like the awful smell of ethanolated gasoline. The better smell of Colemans both raw and burned is the primary reason I use it. Another reason I like Colemans is that it does not go bad. Non-ethanolated gasoline may be available at marinas, and Pure (look it up) gasoline has blends that do not have ethanol. Another option is avgas, that smells good and does not go bad in the tank. It however, does have lead in it. Methanol can be had at speed shops (take your own container) at about $5.00 a gallon. It may also be available at car, cycle and go cart racing tracks. You have choices, it is up to you to do some research and decide. Good luck.
Old 04-24-2016, 06:01 AM
  #35  
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Thank you guys, yes the yellow bottles of heat are methanol, but that is not a cost effective way to buy it.. I have a lineup on free methanol from a buddy that races modifieds. I've already ran the calculations. Between a gallon of new nitro fuel, free methanol, and a quart of klotz oil I will be able to mix up 4 gallons for a about 34$.. Or 8.50$ a gallon. I Will probably give the big cat a try. It's already mounted Nicely and setup. I ticked it over with a squirt of fuel in the carb and it popped right off. Maybe I wil have some luck.. And now that I received a lot of info on glow plugs and fuel. I might have success

Last edited by Dan33klein; 04-24-2016 at 06:04 AM.
Old 04-24-2016, 07:49 AM
  #36  
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Have read all the replies to your question and find them very interesting.

Based on my experience running a Sig 1/4 size clipped wing Cub for several years and a bunch of ST 2500 and 3000 engines in various planes over more years, here's what I've found.

My Cub flew with an OS 1.08 because that was the largest glow engine that I could get at the time. I did not want a clunky Quadra or any other gasser as I preferred to have everything enclosed inside the cowl. Power was more than adequate. On floats, at instant full throttle from idle, and full up elevator, there was no take off run at all. It was instantly into the air and climbing without hesitation or lack of speed. Most likely I'll build another one day. My preferred engine for that will be an OS FX 1.60. Still want all the engine and exhaust inside the cowl. And I want the plane to be on steroids. The 1.08 was nice. I'd just like more power, ability and excitement.

The ST2000/2500 will fly the plane. But it's much bigger and heavier than the OS with now power advantage.

My large Tigres all ran flawlessly with Fox idle bar plugs. Not an issue or a flame out due to a plug. Some people preferred K&B plugs yet I never had them work reliably. Why? Who knows? My fuel was a maximum 5% nitro. My preference was Byron fuel since it had the right composition and content oil for the Tigre and results were consistent.

The large cats were not difficult to set up. You need to take the time to learn how a Super Tigre works. It's much different than say an OS or Enya engine. As with anything else, once you learn their characteristics, they are very easy to start on the first flip every time - if they don't you've done something wrong - and run reliably with no need to constantly fiddle and adjust. My carb of choice was the OS 7D which gave much better performance though than the stock carb. Fuel consumption was about 1 oz. per minute. To me, with the low or no nitro blends and not excessive consumption, fuel cost was not an issue.

As for gas engines, I run Zenoah, the main reason being that I can get magneto ignition. I despise batteries. They always fail - always at the worst time. They require constant babysitting and still they fail. Doesn't matter what type - NiCad, NiMh, lipo, carbon-zinc, lead acid wet cells, gel cells or whatever they are. So the fewer batteries on which I depend, the better.

As for selling the Tigre, do so before you get too itchy to run it, bench or otherwise, since that will devalue it. The best return comes from new in the box, with the original box and paperwork. Even with just a bench run, it's no longer new in the box and devalued. Forget selling it on this site. Go to the bay. Check what's happening there with current listings and recent sold items. Somewhere about $100 + or - sounds to be about the correct range. Put whatever you get into the replacement engine.

If you don't care about what you'd get selling the Tigre, by all means, run it - first on the bench. It will not come into its own and settle down to what a Super Tigre is until you've got some time on it. You've also got to learn its characteristics. This is easier on the test bench than in the air. Prior to this, you may think that it's a piece of junk and that it will never be worth anything.

Finish the break in by flying it. The ground on a bench is not a good place for that.

Whichever route and whatever engine you ultimately choose, enjoy your Cub.
Old 04-24-2016, 11:28 AM
  #37  
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I would sell it if you could. I am running a DLE 35 Rear Carb in my Giant Hanger 9 cub. Sips fuel and pulls like no tomorrow. Attached is a Video Taken at Warbirds Over Delaware. Starts 2;00 minutes in.

Cut and paste the link!


https://www.youtube.com/watch?v=foodJ1SzaFs

Last edited by LUDS96; 04-24-2016 at 06:51 PM. Reason: Link
Old 04-24-2016, 06:14 PM
  #38  
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Thanks for the detailed post and all the information. Seeing that engine mounted and ready to
go, I couldn't hold back. I had a gallon of 10% nitro and 16% oil fuel laying around so I filled it up and it started first prop flip with an osF plug. I ran about 3/4 of the gallon through it on the ground per the super Tigre manual. it idles great, transitions great, and runs good at full throttle. Swings a 18-6 wood prop at 7800rpm. Seems pretty good for not being broke in yet. I have the radio system done and it's ready to get in the air. I wanted to maiden it today but it was too windy. Picking up a gallon of 5% nitro 16% oil next week. That will be two full gallons of break it fuel. Then I'm mixing my own. A gallon of off the shelf 15% fuel, add 3 gallons of methanol, add 1 quart of klotz oil. Should leave me with a good blend of fuel. Around 3% nitro and 11% oil. Cost should be around 8.50$ a gallon with free methanol. Will the fuel being this cheap I will run the big cat unless it gives me trouble.
Thanks for everything guys, will report back with results.
Old 05-10-2016, 06:16 AM
  #39  
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Just an update guys. I have about 1.25 gallons through the super Tigre. First 3/4 was on the ground, and now I have about 5 flights on this cub and I am really enjoying it. Engine seems to be running good. A little rich through the mid range but it is still being broke in. Once the second gallon is burned I will be Switching to my home brew fuel I just finished last night. I mixed 4 gallons and the final mix is 4.5% nitro
10.5% lube should be a good mix for this big cat. Hopefully I receive reliable performance from it.
Old 05-10-2016, 08:10 AM
  #40  
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Originally Posted by Dan33klein
Thanks for the detailed post and all the information. Seeing that engine mounted and ready to
go, I couldn't hold back. I had a gallon of 10% nitro and 16% oil fuel laying around so I filled it up and it started first prop flip with an osF plug. I ran about 3/4 of the gallon through it on the ground per the super Tigre manual. it idles great, transitions great, and runs good at full throttle. Swings a 18-6 wood prop at 7800rpm. Seems pretty good for not being broke in yet. I have the radio system done and it's ready to get in the air. I wanted to maiden it today but it was too windy. Picking up a gallon of 5% nitro 16% oil next week. That will be two full gallons of break it fuel. Then I'm mixing my own. A gallon of off the shelf 15% fuel, add 3 gallons of methanol, add 1 quart of klotz oil. Should leave me with a good blend of fuel. Around 3% nitro and 11% oil. Cost should be around 8.50$ a gallon with free methanol. Will the fuel being this cheap I will run the big cat unless it gives me trouble.
Thanks for everything guys, will report back with results.
Just an idea. Convert the big cat to electronic ignition, even using glow fuel, and your "miles" per gallon will increase. Enjoy!! Glad your are happy with the ST. I love my Como S90. I would like a big one, will have to check ebay.
Old 05-10-2016, 08:18 AM
  #41  
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I emailed a gentleman about converting it to gas but the cost was just way to high. I wonder what it would cost for the ignition. I thought about finding an OS7D carb for the heck of it. But I pry won't dump any money in this engine other than fuel. If I spending any money it will be towards a gas engine.
Old 05-10-2016, 08:22 AM
  #42  
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Originally Posted by Dan33klein
I emailed a gentleman about converting it to gas but the cost was just way to high. I wonder what it would cost for the ignition. I thought about finding an OS7D carb for the heck of it. But I pry won't dump any money in this engine other than fuel. If I spending any money it will be towards a gas engine.
Sorry, I meant just adding the ECDI and a spark plug and running on glow fuel. Reported to increase fuel economy, performance and user friendliness. If you want to sell your Supre Tiger, let me know by PM. Thanks.
Old 05-10-2016, 08:30 AM
  #43  
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No I understood you, I'm saying to convert it to run on gas was really expensive, I'm assuming the ignition is the most of that... I will send a PM. Of course if I was going to sell it I should have when it was brand new. But it isn't even broke in yet and runs great. So no issues.
thanks

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