Red Max

I just purchased a used Super Tigre 3000 engine, it has 325 stamped below the 3000. Does anyone know anything about this engine, H.P., displacement, how it would compare to a gas engine of its size, etc? It does not have the carb on it. I want to get another carb, and I was reading on another forum where the ASP 91 two stroke carb works really well, or does anyone have a carb for this engine, or know where I can get an upgraded version? I have read where the old carbs gave some problems. Any info would be greatly appreciated. It was mounted on a Stinger 1.20 airplane, and I was thinking about putting a gas engine on it. I dont know how well this Super Tigre engine flew this Stinger, and I want to make sure it has plenty of power. I dont do 3-D, but I dont want it to be underpowered.

spaceworm

Have you thought about converting to gas or glow gas? Since you need a carb anyway, get a walbro, fit an electronic CDI and a spark plug and "get your gasser" for your 120 plane. Just a RANDOM rational thought.

Good luck

Red Max

That sounds really interesting. I have a Walbro carb. How would you mount the carb? The head would have to be fitted for a spark plug. How would you do the glo/gas conversion?

spaceworm

Here are some links, both pro and con comments. Take a look. I plan to convert a COMO .90 and an ASP 91 and 1.08 to gasoline with a CDI and 1/4-32 spark plug. I am not looking for max performance and will use plenty of oil and NOT replace my connecting rod bushings for bearings. I need to source an adapter for converting the carb adapter to fit a Walbro to the engine. I will use an RCEXL CDI. Good luck on yours. Where in VA are you? PM me if you wish.

Sincerely,

Richard/SPACEWORM

spaceworm

Uh, let's try the link thing again:

http://findarticles.com/p/articles/m...g=content;col1

http://www.rcuniverse.com/forum/m_92...tm.htm#9278744

http://www.rcgroups.com/forums/showthread.php?t=1004344

Starting & Running Big Super Tigre and Moki Engines
By Ed Moorman
If this is your first big glow engine, and by that I mean a Super Tigre 2300, 2500, 3000 or 3250, or a Moki 1.35, 1.8 or 2.1 you might find it intimidating to operate. You also may have heard they are hard to run and require a lot of special care and feeding. Nothing could be further from the truth. The big engines are easy to operate after you know how. They run well and seem to last forever. You will have to do a few things differently than you did with a .40 or a .60. But they aren't hard. Think about moving from a little Cox .049 to an OS .46. There are some differences, right? Same for moving from an OS .46 to a Moki 1.8.
FUEL LINES: The little Cox uses small fuel tubing and the OS .46 uses medium tubing, so it is reasonable to expect the large engines will require the large stuff. Large fuel line, large brass tubing and a large hole in the fuel pick up clunk. Using medium fuel tubing on a big engine is like sucking a thick shake through a small straw. The engine will lean out in maneuvers and have an inconsistent and sensitive needle valve settings when using medium fuel line. Here are my recommendations:
Use a Sullivan or DuBro fuel tank, or some kind with replaceable brass feed lines
Drill out clunk or replace it with chain saw or brush cutter type filter clunk. A lawn mower shop or hardware store will have these. Take your tank so you get one small enough to go through the opening in the tank.
Drill out the holes for the fuel feed line in the two plastic caps and replace the brass tubing and the fuel line inside the tank with large size tubing, 5/32 instead of 1/8. Zip-tie the tubing on.
Use large fuel tubing from tank to engine.
If you use a DuBru filler valve, use the large one
Super Tigre engines have a small fuel nipple on the carb. Use a short length, about 1 inch, of medium tubing to attach to carb and splice it to the large fuel line. If you don't plan to remove the tubing from the carb to refuel, you can zip-tie the large tubing to the carb nipple.
FUEL:
Break your big engine in on regular 10% model fuel for 2 gallons, running slightly rich. After 2 gallons, you can switch to a low oil, big engine fuel such as Morgan Fuels' Omega Super-T or FHS Red Max ST3000 fuel, 10% nitro. Both are formulated for big glow engines like the Tigre and Moki.
Use no more than 10% nitro. These are high compression European engines, originally design for FAI, no nitro fuel. Anything greater then 10% nitro is a waste of money. You won't get you any more power, and it will cause the engine to run hot and detonate. In hot weather if your engine "crackles" you probably have detonation-not good. You need to run a lower nitro fuel or add a couple of head shims. The engine distributor will have them.
High oil, regular fuel does not idle as well as the low oil fuel. The Moki runs better on regular fuel than the Tigres.
If you were wondering why you need less oil in the big engines, the fuel/oil mixture a volume which is a cubic function. The parts to be lubricated by the oil are areas which are square function. You know cubic inches and square inches. As displacement goes up, the volume increases proportionally faster than does the area, so the need for oil percentage becomes less. The fuels are around 14%-16% oil, about like 4-stroke fuel for oil content.
CARBS: The original carb on the Super Tigre engines worked very well. It was the same one as used on the .60, so it had a fairly small diameter throat. Many people found the OS 7D carb from the OS .90/1.08 would fit and it had two advantages. First, it had a larger diameter throat and would give more power. Next, the 7D could also be fitted with an in-flight mixture control. This feature is popular on scale planes with tightly cowled engines. Later, the carb from the ASP .90/1.08 became popular even though it didn't have in-flight mix since it was cheaper than the OS carb. I currently have ASP carbs on all of my 3000's.
Later on, Super Tigre designed a new, larger diameter carb. This one didn't work very well at all, and many people had trouble running the engine. After the Moki started becoming popular, Super Tigre designed a new, much larger carb. It was used on the last 3000's and the new 3250. I haven't run one on a 3000, but the one on my 3250 is excellent and there is no reason to buy a replacement carb.
The carb on the Moki is excellent. I don't recall ever changing the low end adjustment. The top gets tweaked a quarter turn or so on very humid days, especially early mornings on foggy days with low clouds.
MUFFLERS: My choice for either Super Tigre or Moki engines is the Bisson muffler from Canada. Gerard, who imports the Moki engines, also is the importer for Bisson. Their Pitts style muffler is compact and takes very little power from the engine. The Slimline also works well. J-Tec makes a muffler which can be hidden in a scale plane fairly easily. Bisson also makes a very compact Pitts muffler for the OS .40 & .46 engines for a clean installation on those small Extras and other planes with side mounted engines.
PROPS: These engines, although all are about the same size, have different power bands and run differently. The ST 3000 & 3250 are high torque engines, the Moki and ST 2500 like to rev. If you still have the instructions which came with the ST engines, check out the rpms for best horsepower. The old 2000 got its max hp at 13,000 rpm, the 2500, at 10,000 rpm. Both these are revving engines. The 3000, on the other hand, is rated for best horsepower at a low 7900 rpm. This should tell you the 3000, and likewise the 3250, are high torque engines that ought to be loaded down. They should normally be propped for about 7000-7200 on the ground so they will unload in the air to their best operating rpm. Here are my suggestions for a normal application. For a big radial cowl, you will probably need a longer prop.
-ST 2500: 16-10 or Zinger 18 6-10
-ST 3000: 18-10 or Zinger 18 6-10. On my planes, an 18-8 turns up but the plane doesn't seem to go anywhere. If you are flying a sport plane and want to pep up your 3000, try a Mac's tuned pipe and long header. This combination will really turn a Zinger 18 6-10.
-ST 3250: 18-10, 20-10, 18 6-10. The 2 cubic inch 3250 will turn the 20-10 all day long. Loads of torque.
-Moki 1.8: 18 6-10, 18-10, also 16-10, 16-12. Likes to turn, but will also turn a big prop. With a tuned pipe and a 16 inch prop, the Moki will really turn. Many people like the 16-12 prop and Bisson muffler combination on the big Moki.
18-8 props: Although many people like this size prop, I have not had good results with it. High rpm, no speed.
STARTING: Never, never, never flip the prop through compression on these big engines like you do a small engine. These are high compression European engines made for no-nitro fuel. If the engine is even slightly wet, it will try to tear your hand off. Here is a procedure for 1-flip starting:
Open carb & choke 3-4 times.
Flip prop over 8-10 times to get fuel up into cylinder. You will hear a squishy sound when it is wet enough. If you don't get the pop-squish when you flip it over, choke it again.
Close carb, set idle trim up and hook up battery.
Put prop up against compression, then slap it BACKWARDS.
The engine turns backwards until it hits compression, then backfires, which kicks it forward. Normally, this starts the engine. If you use a spinner, you can grab the spinner and twirl it backwards to start.
RUNNING: There is a tendency for many people to run these big engines too lean. Fliers used to the sound like a screaming .46 try to adjust their big Tigre or Moki to sound the same. None of these engines will turn an 18 inch or larger prop that fast. Tune for max rpm, then back off a few hundred. If you are trailing a little smoke at the first of the flight, the engine is probably set correctly. It will lean out slightly as fuel burns down. If you have set the engine for full lean at the first of the flight, it will go too lean as fuel burns down and more than likely over heat by the end of the flight.

Gabrielsande

Hi there here is a video of my ST 3250 gas conversion, used a Walbro carb,and an autoadvance CDI ignition system, on the bench it runs smooth and it drops 6400 revs with a menz 18-10, I should use a 18-8 as with glow the power pick is 7,700 with a 18-8 so I think is not bad for a conversion, I made a ring to mount the sensor, and a flange to fix the carburattor, Im using amsoil dominator at 25/30-1, temperature at full throttle for a couple of minutes goes around 280F transition is good so let see how it flyes! and how long it last! [link]http://www.youtube.com/watch?v=pzYmPsxzoVc[/link]

Red Max

Your engine sounded good. Let me know how it does. Right now I am planning on using mine on nitro fuel. I purchased an ASP .91 carb the other day. I had to make a tube from a piece of aluminum tubing to fit over the carb base and to make it fit into the engine block. It still lacked a little bit to fit tight, and I wrapped a couple of rounds of aluminum tabe around the tube and put silicone sealant around it. I hope this will work. I tried to get an O.S. 7D carb on e-bay last weekend and I was outbid. The os carb would probably have fit without a flange. It just went for more than I wanted to give at this time. We are covered up with snow and it looks like it is going to be quite a while before I can get out to check out anything.

Gabrielsande

Hi the engine sounds very good, I fitted it to 70" edge 540 today, I think this plane is to small for it but I used a 90 ic, 120 ic ,26cc petrol (wich was very heavy and slugish) and it can cope with the weight, today I just mounted the engine and fitted the wing just to check how violent the engine will be to the frame, (petrol engines shakes a bit more than ic) started it and it was very smooth, it was vibrating less than with the crrc pro 26cc, holded the plane up and it was pulling a lot, the frame is an old cmpro on the heavy side, im using it just as a test bed.

One thing about this conversions is the fact of petrol engines uses a neddle bearing on the conrod I think is not just for the difference on lubrication, just based on my previous attempts (I burned a couple of engines trying), at one point I was trying with a TTpro 120R with the ignition on ,walbro carb and the timming right it was idling ok and pulling a lot but the strokes were vilolent and despite having removed 3 mm from the compresison chamber, I know these TT 120r they are tunned to the limit they go well over 10k while ST are around 8K, less revs more torque, thath's wy Im trying with this one now.
Anyway, when I was trying the TT120 and the strokes where very sharp like a machine gun, I switched to glow fuel, swaping the carb for the stock one but I left the ignition on, aaaand it was doing the same,running nice but with violent strokes, so put the glow plug back and it was very smooth!, so I think because the glow fuel ignites more progresive, ex, the glow plug is glowing and as the piston goes up compressing the mixture it starting burning earlier and progresive, using the spark ignition piston goes up and spark fires the mixture all at once, that's wy (I think ,is only my theory ) they shakes more, I think they must have a difference on the porting timming, and I think that's wy the normal brass bearing will not survive much on petrol, Im used up to 20% oil on the TT120R and it was ok on the bench like te ST but in the air didn't last 5 minutes. I know if you are flying a scale model purring around the skyes it will be ok, but abusing them on 3d machines or acrobatic planes don't know I want to hear more about this of people flying them for long periods of time without problems or burned conrods!.

Just browsing in to a bearings website I found a needle bearing which mesures 8mm in 12mm out and 10mm long, almost the same size of the ST 3250 conrod big end, Im going to order a couple and a new conrod to modify and see if will be ok.

Wy all this hassle?? well, one some of us enjoy getting our hands greasy, Im a mechanic and had enough of doing cars during the week! and doing a model engine overhaul is much easy!, but the thing is Im flying a 70" goldwings 3D sukhoi su26 im love this plane to bits, at the moment Im using a CRRCpro 26i 26cc, and the power and weight is more than adecuated, but Im not happy with the engine quality it cost me under 130 euros new with ignition exhaust etc, is very good looking comes with a walbro carb and cdi autoadvance unit , but after 4 hs running it started nocking a bit, so took it apart and for start, 2 of the 4 cranckase bolts were lose,allowing the mixture to get lean when pulling, because the threads were stripped from factory, becasue they used big washers which where dragged down the bolt location betwen the cranck ribs, putting more pressure on the threads.

Also found on the cranck shaft under the prop hub, by the spares manual should have a oil seal a cricle clip and then a bearing, and other bearing on the back, this one has instead the oil seal an other sealed bearing then the clip and then other sealed bearing (both sides sealed), they confused one oil seal with the bearing (same diameter), but being these bearings in no contact with fresh oil and being spaced for the circle clip on the outer rim when tighening the prop hub, the ball bearings where extra loaded on they tracks, so having just few hours running they where allready rough, so order a new cranck shaft assy,bearings and oil seal, spares where cheap, re-tapped the threads and got rid of the washers, used just locktite on the threads, it runs very nice and smooth again, but saddly I discovered on these engines crrc pro use very cheap neddle bearings in fact they are roller bearings, they are very spaced betwen them only 9 rollers where could fit 15, so the pressure of the piston going down is just on this 9 rollers and the pressure is not eaven on the journal, so I think this engine will not last much! if goes again will replace the cranckshaft again its only 10 euros. and sell the engine. it put mi mind on an evolution 26gt, they are light and they comes with proper neddle bearing on the rod yes they are twice the price of crrc pro, but it will last few years!!.

Please keep me informed on any progress with conversions.

have a look to the just engines website [link]http://www.justengines.unseen.org/acatalog/Customer_Feedback__and_Our_Experience.html[/link]

there are few people doing conversion here


Regards!


Luis

Red Max

Do you think the Super Tigre would have more power running it on nitro instead of on gas? I know nitro costs more and does not last as long (flight time). I just dont believe I would have enough experience to do the conversion to gas. I used to work on chain saws in my spare time and used to run a go cart on chain saw engines. I have seen the first go-cart that was introduced in the 1960's. They all ran on re-furbished chain saw engines at that time. I still have the first go-cart I have ever owned. I have had it since around 1964 and it still is in great shape. I hope to locate a good chain saw engine to put on it , around 7 h.p or more. I would love to find two engines that are exactly the same, as I have two engine mounts on the back of the cart. By the way, you have some really nice looking planes.

Gabrielsande

thanks dude! yes sure You lose some power, but here in uk a gallon of glow fuel it cost around 12 euros ,running the engine on glow it consumes about 450cc in 10 minutes,about 10 flights per gallon, petrol cost is 4.5 euros per gallon and you do nearly 30 minutes on the same tank+having a ignition system means no more dead sticks and more reliable lower speeds and transition

w8ye

My Feedback: (16)

When you fit a needle bearing to the Super Tiger crank pin, you will have premature failure of the crankpin as it is not hard enough for the needle bearings.

Red Max

Let me tell you what I did to my 3250 ST. I got it at a swap meet, did not have a carb and no sleeve in the engine block where the carb goes in. I bought an ASP .91 carb, which was recommended as a good carb for this engine, and it was too small where it goes into the block. I found a piece of aluminum tubing and it fit real tight around the carb base, but it still lacked a little to fit tight in the block. I wrapped a couple of turns of aluminum tape around it, and then cut some aluminum strips from an aluminum pan and wrapped it, lettint it overlap at one point. It then inserted fairly tight, and I put some muffler glue around the top. I tightened the bolt that goes through the carb. If I try to put sealant around the carb flange that I made before I insert it, it just pushes the sealant (glue) out. Do you think this set up will cause any problems, or do you have a better suggestion?

w8ye

My Feedback: (16)

As long as it is sealed, it should be OK

spaceworm

Is the crank pin of the COMO C90 (ST S90) hardened or not, and if not can it be suitably hardened with Caseite(?) to hold up to needle bearings? Is Caseite still available if that is the name for what I recall of a surface hardening material? Or, how can you harden crank pins? TIA

w8ye

My Feedback: (16)

I'm not an extreme authority on this but have the opinion that the crank is essentially 4340 steel forging at a hardness of Rc @ 44. To be good for the bearings it should be at a Rc of 55.

This is a oil hardening steel and to heat treat it will ruin the finish, As it is already to size, this presents a problem.

Maybe someone else has been through this already with a solution such as a hardened sleeve or something?

Gabrielsande

Hi there, right the easy way to attach that carburator is just get the carb diameter, then the cranckase diameter (where carb goes) and just ask an engienner to make a sleeve on the lathe, I paid just $15 for the big flange he done to fit the walbro in to it, I guess a small sleeve will be cheaper, and at the end it will be as the original one, you want to keep it simple and with less weak points, then what im learning about conversions you need a needle bearing on the conrod, and a hard pin on the crankshaft, I think they must use something like piston pins to machine and press in to the existing one.
Anyway I found this guy here in few forums, Ken Lambert who is doing these conversions, Im just waiting to see how much will be to mine, if is not too bad I might do it before sending my conversion to the sky.

keep in touch!

w8ye

My Feedback: (16)

Ken Lambert is good and has a lot of experience with this

Look here

http://www.rcuniverse.com/forum/m_5550647/tm.htm

Gabrielsande

sorry guys I just bought a new saito fg30 to cure this problem (found it on ebay still on the box bagged of someone who gave up to a big project paid under$500 , so the st3250 converted+the cmpro edge+ a crrc pro 26i+an other cmpro edge 540 frame will be on ebay soon to pay for this one ,funny enough the petrol saito don't use needle bearings on the conrod, could someone explain this to me!! the other problem Im facing with this engine is because the carb is on the back ,[link]http://www.macgregor.co.uk/saito/fg30.htm[/link] the engine will be way foward, so two choices using a normal plastic mount, so I can slide the engine back and cut a hole for the carburator,in the firewall, doing this I cant use the nice supplied alloy mount which they say it helps cooling, or cut the firewall completly and re glue it an inch 1/2 back, I migh post few pictures so You can help me to decide .


Cheers


Luis

spaceworm

[quote]ORIGINAL: Gabrielsande

"..,funny enough the petrol saito don't use needle bearings on the conrod, could someone explain this to me!!"

20:1 gas to oil mix (as recommended by SAITO) apparently allows no needle bearings??


"...the other problem Im facing with this engine is because the carb is on the back ,[link]http://www.macgregor.co.uk/saito/fg30.htm[/link] the engine will be way foward, so two choices using a normal plastic mount, so I can slide the engine back and cut a hole for the carburator,in the firewall, doing this I cant use the nice supplied alloy mount which they say it helps cooling, or cut the firewall completly and re glue it an inch 1/2 back, I migh post few pictures so You can help me to decide "

The metal mounts I use (for my 120 ABC and 180 AAC) have enough beam to allow mounting the engine with the carb behind like the Saito has. Does the Saito thus mounted cause the weight (and cg) to be too far forward? Or, is the problem with the fit of the cowl with the engine this far forward? Is the existing firewall completely adequate as far as strength? If not, perhaps moving it back along with reinforcement would be the answer.

I would use the metal mounts as recommended by Saito for both cooling (additional heat sink mass) and for rigidity to reduce vibration and shaking. That's what I do.

Best regards, SPACEWORM/Richard/SAITO Club #635

Gabrielsande

Hi yes it will be nice to leave the original mount, but the, prop hub sticks about 60 mm further out of the cowllinethan with the crrc pro 26i, and the crrc pro is against the firewal, I can move the cowl 20mm foward, but will need to drill more suporting holes and still 40mm to go!, so I have to work out how to move the firewall back the tank is nearly over the wings so there is nothing on the box, but is one of those light frames, and I have to be careful not to add too much weight to it it flyes very well with the crrc pro, Imswappingit just to have a tad more of power and I know the saito it will sound better and last longer. I will post more pictures once I have the engine to compare against the crrc pro26i thankss

I bought this plane from china, www.cyclonetoy.com ,sold in uk also from www.globalrc.com.uk, and if you want to see nice pictures and videos of this plane flying go to www.axarmodel.com

spaceworm

After seeing pics of your plane, what I would do is just make a hole in the firewall to clear the Saito carb and then use the metal mounts. The structure looks very light so i would reinforce it as much as possible without adding too much weight. Carbon fibre purhaps? Just curious, does the FG30 produce that much more power than the 26i? Of course no stinkin' 2 stroke is gonna sound like a 4 stroke. ( I have both!!) Good luck

Gabrielsande

Hi there, the saito mount ends just after the carb so there is no way to use the alloy mount, to get the carb in, only if I use a 2 normalplastic separated mounts, or probably machine the alloy one to allow me to move the engine back. saito is 158mm from the back of the mount to the prop hub/cowl line crrc pro just 95mm

About power crrc pro vs saito fg30

Crrc pro 26i

weight 1150 including mount and ignition
power 2.4 ps at 9000
practical rpm 1600-8000
prop range 16-8/10 used a, 16/8 on the sukhoi goes fast, but just pulls from hover with a 18-6 goes slower pulls better from hover still to try a 17-7 I have, ground revs 18-6 prop 8400
Done the conrod bearings allready in just 3 hs now using more oil than recommended, the conrod needle bearings is a roller bearing with just 9 very spacedI don't think it will last abusing it.
Very stable, idles for ever, no dead sticks
not easy to start by hand despite priming or using the choke, if you kick the blade against the hub to reach more flick speed it starts after 10 attempts, not possible on the sukhoi for the big cowl, so electric starter allways,and starts in seconds
cosumption Im flying on a 350cc tank and it does nearly 30 mins mixed fly


Saito fg 30

Weight with mount,ignition and exhaust 1480g
practical rpm 1700-9000
prop range 16-8/10 17-6/8 18-6
ground speed on a 17-6 8700 rpm


I think it will be almost the same, but probably more reliable. good looking and better sound and better torque at lower rpm.
is a bit heavier, but at the moment Im using a 2cel lipo regulator for the ignition and two separated 4,8 2500mah packs trough 2 switches separated leads in to separated channels for a level of redundancy, and these batteries are against the firewall, to get the cg rigt and still a notch tail heavy, with the saito I have to move them back and I could get just one 6v battery pack instead th two 4.8s, to compensate for the difference.

Thanks!!

mike31

My Feedback: (67)

I have run ST 2k, 3k and 4500 sizes all on medium fuel tubing with no problems. The fuel is limited by the opening in the inlet nipple at the carb anyway. If there is a larger inlet nipple available please let me know where I can find one to try. Large fuel line does get more fuel to the carb but again is restricted to the opening in the nipple. Drilling the nipple may allow more fuel but leaves the nipple wall thin enough to break through. Just my observations.

Hobbsy

My Feedback: (102)

To add to whats already been said, the big Tigres are not high revvers and there is nothing wrong with that. They are strong mid range torque engines which is perfect for turning propellers. The 3000 will last longer than just about any other engine and when you think its worn out get a new Frank Bowman piston ring for about 11 bucks and it will be as good as new.

flyingagin

I drilled my fuel nipple out, and tnen soldered a couble or so turns of copper wire over the end to make a nice lip. I then used large fuel tubeing from the clunk t o the nipple and replace the brass lines in the tank with bigger ones. That was a pain as I had to rework the cap to allow them to fit thru it. I also soldered a couple of turns of copper wire around both ends of the brass lines inside and out. All fuel lines connections were then saftied with Some stell safty wire over the tubing in front of the lips on the brass lines and and clunk and and engine fuel nipple. I made very sure I had NO BURRS OR SHARP EDGES ANYWERES. The fuel tubing ain't comming off with out tools.
11% oil.
I Lost the muffler in a cow feild so made one from a hair spray can. Can is to big and I will replace with an aluminum Pepsi bottle like the long neck aluminumBudwiser bottles. I think the LARGE hair spray can is not only butt ugly but is way bigger than needed. The aluminum Pepsi bottle has a volume (if I calculated correctly) of around 15 times the engine displacment, and the hair spray can is at least double that.
Power went up markedly and noise was much lower.

A lot of work over all but then I love to tinker with these things If I could not tinker it would not be any were near as much fun or satisfaction.