Granpooba

My Feedback: (5)

Have been in the hobby for so many years that I do not care to admit, but have never run into this problem before.

Have a Super Tigre .61 mounted on a Bobcat 50, which for some of you, the engine is mounted on the aft part of the fuselage, running a pusher prop.

To start out, I have no problems starting the engine, as long as I prime the carb. It starts readily, but runs for just a few seconds, off the the priming fuel. Engine is not drawing fuel from the tank. [>:]

What I have done to date is to pull the tank and check all fuel lines, placement, clunk placement, pressure line etc. Also, pulled the carb and checked for any blockages, but found nothing wrong with carb, tank, fuel lines, etc, etc. [] Put everything back together for another try and guess what. Repeat of original problem, will start and run on primer fuel but does not draw fuel from tank.

Next solution tried was a completely new tank, temp mounted to fuselage, with all new fuel lines, clunk, etc. Result not good. Same problem, engine will not draw fuel. [&o]

I am now at a total loss fellows, that is why I am here asking for some advise or possible solutions.

speedracerntrixie

My Feedback: (29)

Blow through the vent line with the fuel line off the carb. You should be able to force fuel out the carb line pretty easy. If you can do that I would check the low speed needle. Sounds like it may be closed.

Granpooba

My Feedback: (5)

Checked the low speed needle and it was open approx. 3 1/2 turns. Does not seem likely that should be causing the problem. [&o]

Thinking that I may just be swapping out engines. I have other Super Tigre .61's. Maybe one made in Italy will work.

Live Wire

If you are like me , I put the fuel tank in backwards. Clunk was at the wrong endand I have put the line from the carb to the vent.

Granpooba

My Feedback: (5)

Nope, double and triple checked that for a solution.

When the problem repeated, I tried a second tank on the outside of the plane. That one did not allow fuel to be drawn either.

Live Wire

And you could check the bolts in the rear crank case cover, if loose could have a crank case leak.

SRQFlyer

My Feedback: (17)

Make sure the pressure nipple in the muffler is not blocked. If it is, the engine is trying to draw a vacuum on the tank and will only run a few seconds.

Good luck!

Jim

Granpooba

My Feedback: (5)

All good suggestions guys, but having been in this hobby for quite some time now, I usually check everything during installation. Always have checked all the bolts on a new engine going into a model, and have always checked mufflers, pressure nipples, fuel lines, etc. Have always had great success with my models, having never had a problem, until now.

I will most likely be changing out the engine within the next couple of days.

Thanks for your help and suggestions.

jaka

Hi!
Sounds like the pressure nipple is clogged! Check it one more time!

Granpooba

My Feedback: (5)

Have checked everything twice and three times. Still can not come up with a solution.

Friend of mine states that perhaps just by chance the engine is ported wrong. But I find that hard to accept.

Thus my only solution will be to change out the engine and muffler within the next couple of days.

First time in my life I have ever seen anything like this. Have had engines that ran a little rough, lean, rich, etc., but were all able to be tuned. Never have had one that would not even draw fuel from the tank.

Getting to the point in life, when I am beginning to think that I have seen it all .................

jester_s1

The Super Tigre on my Ultra Stick won't draw fuel through a dry line, but it does fine if I prime it by spinning it with the muffler blocked. It's on a taildragger and can't overcome the gravity to get the fuel from the tank. I even have to be quick about starting it once its primed or the fuel in the line will roll back into the tank and I have to start over. Are you by chance priming it by squirting fuel into the carb from a bottle and expecting the engine to pull the fuel through the line itself, or is the line full of fuel when you go to start it?

JohnBuckner

My Feedback: (1)

If you are priming by blocking the exhaust or the venturi are you first opening the throttle when you do so? Also sometimes the fellow will tend to operate the engines with the midrange screw to far in and this too affects starting fuel draw.

If you do choose to change out the engine just for your information the mounting bolt pattern, spacing and case width requirements of the TT .61 Pro are identical with the OS .61FX, OS .55AX as well as the .65, .75 and .95AX's.

In addition the muffler spacing and fit are also all identical of the engines I mentioned above. In other words all can use the same pipe or mufflers also. I just completed the reengining of a Strega Bronze warbird pylon ship with a TT 61 pro into a Silver cless racer very simply with .95AX and using the long version Ultra thrus pipe intended originally for the TT.

Needle valve provisions in cowling etc. will have to change.

John

JohnBuckner

My Feedback: (1)

Another thought just occured and this I know is the case at least with the older oriinal TT .61 Pro without the rear slanted needle valve of the later Pros. The only two TT 61 pro I have ever used are two I purchased originally from tower before they went to The the California outfit.

What I found was since I operated a great number of TT .40's for certain competition events and it was required, was that even though the TT part number was the same the .40/.46 needle will not function with tt 61 Pro. I must have lost one or mixed it up with all the 40./.46 needles and that second engine became useless at which point I put it in the useless pile.

Now years later I bought an old original tt 61P carb for a buck or so and using that needle was able to reactivate that engine successfully.

I,ve no idea if this applied to the later 61Pros with the rear slant carb or not.

John

Pylonracr

The first thing I would do is pull the engine and put it on a test stand. Use the tank and the muffler from the plane first and then start swapping parts. If you can Choke it with your finger it should draw fuel. Is this an old engine? Has it flown before? If so, it should have run when it was used last, what changed?? Was it involved in a crash that could have damaged something, or was it removed to go into another plane? Have you been out of flying for an extended period of time, making the fuel old?

There is no reason it shouldn't run.
Keep us posted, and good luck

Scott

Pylonracr

Duplicate post, Wow this site is working great now!

aspeed

It looks like you have tried pretty much everything. Try putting your finger over the exhaust outlet while on the starter motor to prime. If it starts ok on the prime, put your finger over the hole to give it a boost. The same effect can be to put your finger over the carb when it is running. Oh yes, Safety Forced.Some worn out motors just need a little help til they are warmed up, or just to suck the crap through the carb. Otherwise I would try it on a test stand to at least see if it is the motor, or the rest of the setup like the previous posts say.

Ed Smith

I totaly agree with Pylonracr.

Before I put any engine in any airplane I set it up on a test stand. If it does not run properly on the test stand then the fault is in the engine. If it runs properly on the stand but not in the airplane then it is the airplane setup that is faulty.

Simple is it not?

Ed S

Granpooba

My Feedback: (5)

A lot of good advise, only problem is that it seems like I have tried everything that was mentioned.

Thus, just a few minutes ago, I finished up changing out the Super Tigre for another Super Tigre. Also, even changed out the muffler, for another new Slimline. Changed out the fuel lines and clunk. Did all of this so that I had peace of mind and know I would be starting from scratch. Just got tired of trying to figure out the problem with the original set up.

One thing that is different between the engine that I removed and the replacement is that the original Super Tigre was made in China and the one I replaced it with was made in Italy. Don't know if that will be making a difference or not. Also, even though these engines have been sitting in boxes in my shop, they are both new, never run engines.

Eventually I will try the original engine on a test stand.

Will be trying to start the new set up within the next couple of days and will report back to you folks with a good or a bad report. If you don't hear from me then you will know that the fellows in the white coats took me away for jumping up and down on a model airplane .

JohnBuckner

My Feedback: (1)

Hm seems I made the common mistake of Thinking Thunder Tiger when in fact you originally said Super Tiger making my reply all nonsense, sorry.

John

Granpooba

My Feedback: (5)

Have given up !! As a matter of fact, I think that I have given up on Super Tigre engine in general. Probably only OS and Saito's in my future.

Sold the trouble some plane to a friend .

But I do want to thank you fellows for your advise and time.

speedracerntrixie

My Feedback: (29)

Sorry if this comes off a bit harsh but if you had the exact same issue with the second engine, it's not the engines fault.

JohnBuckner

My Feedback: (1)

Well heck dare I say I have had and perhaps most modelers have had some sort of engine in our deep dark past that I would not even want to sell to an enemy!

There is no shame in moving along to what is most effective for you.

John[8D]

LesUyeda

"One thing that is different between the engine that I removed and the replacement is that the original Super Tigre was made in China and the one I replaced it with was made in Italy.

Super Tigre was origianlly an Itilian engine. Are you certain the original was Chinese?????

Les

Bax

My Feedback: (11)

OK..first off, when you say the idle needle is "open x number of turns", that's a problem right there. You do not initially set the idle mixture by closing it and then opening it a specific number of turns. That's because you cannot "close" it. If you turn it in until it stops, you're probably 6+ turns in, and opening 2-3 turns won't work.

Whether the engine is an Italian-built one or a Chinese-built one, they would be identical. The Chinese versions were built on the same tooling with the same specifications and used the same grade of material. The only difference is the location of manufacture.

Here's how to set the carb:

To properly set up your carburetor, there are a few steps...

Make sure the spraybar is set so that the fuel slot is pointed straight down the center of the carburetor. You will have to look through the carb from the bottom, with the venturi opened to full. Loosen the two screws next to the high-speed needle valve to rotate the spraybar so that the slot is centered.

The idle needle can be seen in the slot of the spraybar. It looks like a piece of wire that has the end squarely cutoff. It should be less than one-half way across the slot when the venturi is opened to full.

The high-speed needle should be opened about 2-1/2 to 3 turns out from closed.

All of these settings are very rich. You'll have to start the engine at about 1/4 to1/3 throttle. Once the engine starts, advance the throttle to full. You can then lean the high-speed needle until the engine is running just rich of peak RPM.

Once you have the high-speed needle set, you can retard the throttle a bit and use the idle needle to adjust the engine. Retard a bit, and adjust. Keep doing this until you have reached the desired idle RPM and mixture. Remember, since we started out with an intentionally-rich setting, the idle mixture will have to be leaned.

Finally, the midrange can be adjusted by rotating the spraybar a hair. Just loosen the two screws next to the high-speed needle and rotate the spraybar just a tiny bit. Either direction is OK. This will help you get a good transition and midrange.

cap 580

My Feedback: (40)

I have been fightiing a super tigre 61 also. My problem is when the plane is airborne. Runs great on the ground. Idles forever and transitions good but when in the air it dies. Tried 15 and 10 % fuel different glow plugs and still the same. I have renamed the plane deadstick and will most likely replace motor with another brand.