Have about 4+ tanks through Thunder Tiger .61 PRO and WHEN it runs - it runs GREAT!!!!

Problem is that it is almost impossible to start - can't seem to prime the engine as it won't pull fuel from the tank. I have a tail drag SIG 4* 60 with DuBro fuel tank - I've checked everything 3 times and the fuel line system is air tight.

When it FINALLY starts - runs perfectly for one tank and then after refueling leads to dead sticks - runs fine until right after takeoff and then quits.

HELP????

Make sure your clunk is not stuck at the front of the tank. Disconnect your fuel and vent lines, insert a brass tube into one line. Pinch one line and blow into the other, then pinch and connect the other line to the brass tube. Let it sit for 10 minutes or so, then unplug the lines. You should have pressure still in the tank. If not you've got a leak somewhere. Also check the carb to engine seal. It may be leaking as well.

Is the tank a lot lower than the carb ?

If all else fails you might consider replacing the carburetor (weak link in Thunder Tiger Engines).

I HAD the .61 and finally gave up and sold it. I replaced the .46's carb and it ran pretty well after that. I still have two .36's.....the older runs great, but last night I had to go retrieve it two times out on the runway after powered landing. The newer one has frequent dead sticks in the air.......Never again Thunder Tiger!!!

Sounds like you are leaking air through eithe the base of the carb or the needlevalve. Check the O rings on both.

Laefd,
Yep sounds like an air leak some place. I'm reading all the TT Pro .61 threads to get an idea of what people are up against since I bought a TT pro .61 for my Aero tug Kadet sr Arf.

Same ole same ole, people cant start them, some people say they run hot some people cant get an idle or a mid range, nobody complains about the top end infact everyone says the TT pro will out turn the OS SX. Interesting.

I guess these engines are like anyone eleses engines it all depends on what you like and how you learned to run and care for model engines.

Good luck

JDS

I have the TT 61 pro im myCAP 232 and love it. Starts up and runs great. Maybe got lucky.

Ditto me skyking424. Both TT 46 and 61's have been very easy to start, and run very dependably for me. The TT in my 4*60 barely gets hit with the starter and it's running!

ANYONE that has ANY problems with ANY modern glow engine (Yes, that is VERY inclusive) needs to learn a bit more about engines BEFORE they start whining about an engine brand/type. I have NEVER had ANY engine perform unsatisfactorily for me after I made sure it was ready to run and tuned properly...all of that with stock parts!

In otherwords...where's your sign?[X(]

Hi!
Agree with Gene!
It sounds as if you just run the engine too lean....
Too high temperature will make the engine hard to start (cylinder have expanded away from the piston wich reduces compression ).
Some advise.
Before each flight ..hold up the nose of the airplane and set the needle somewhat rich from max rpm....hold it upp for 5-15 seconds...dont shake the airplane... Just hold it still with the nose pointing upwards.....rpm should be stable!

Jan K

Are you using an inline filter???...sounds like something is floating around or stuck somewhere close to spray bar. Take out the needle valve and pump a short burst of fuel to back flush it...install a high quality inline filter...I use the Sullivan Crap Trap but there are several very good filters on the market.
I amy be wrong in the diagnosis but it sure does sound like junk in the carb...

well this is good news, i have the same engine the TT 61 pro BB ABC and put it in my tower trainer 60 and flew for the first time in about 2 yrs. and all was good but same with me as well, very hard to start - i had to prime it like all get out and finally got it to run, but then sure enough it dead sticked on me, it seems to run well, when it runs but doesnt last long and then just peters out, i noticed mine seem to like to run on the rich side, maybe i need to make it more rich.

im about ready to pull it out and put an os in it but i here some of folks seem to have great success with it, so im going to keep it in and give it another couple whirls.

Sounds like these engines are running too lean, and maybe not broken in yet. Till broken in the engine needs to run richer. Engines may not have good fuel draw till broken in. The TT 61 should be equal to a FX 61 except they take longer to break in.

I agree with Sport_Pilot on the running lean. I have the TT Pro 61 in my CAP 232 and the TT Pro 46 in the VMar Apache III trainer and both engines run great! I ran them on the rich side for about half a tank of fuel then adjusted both needle valves and went flying. I just bought another TT Pro 46 for a BF-109.

Sounds like to me your low ends needs to open a bit more. I had the TT 61 and it ran like a theif.

I had one and loved it. Sorta hate that I sold it. The .61 likes a rich low end setting and a somewhat rich high setting as well. They do take a bit longer to break in than other brands. Run the engine on the rich side for a while, but not too rich. You do need a higher heat level to break in the engine correctly. When running a bit on the rich side, the engine isn't going to have tha power as it would if it were more lean, but in time it will accept the leaning of the needle and not dead stick on you. Give it time, it'll come around.

John

I have a TT 61 PRO and love it!! I have had it for 3 years now and it has been in three different planes and it is still running strong. Even after I had a hard crash it seem to run better. The only problem I have seen with them is they like to run backwards when they are brand new. Besides that they are great running engines, as far as I am concerned Thunder Tiger is the only glow engine I will buy.

Scotty

I really hate it when someone needs help and we all try our best to help and then they never pop back in to give the results.

Scotty...I have a new TT.61 PRO and it is very solid, runs very well and seems to never need any tweaking. Evertime I fire it up and start to adjust it is already running as good as before. I have a CG Ultimate 300 bipe I am finishing up and I am thinking of buying the TT 1.20 instead of my Saito 180. One of the club members had a CG Ultimate with an OS 1.08 and it was very good in vertical so I may just get the TT 1.20.

I am new to R/C airplanes, however not new to nitro engines. I have been running nitro cars for several years now. The situation I am in right now has to do with a TT Pro 61 that I recently got. It was used, for about 10 flights, when I got it. I put it in my Ultra stick 40 which made the plane scream. I was told that proper break in procedures were followed and from the performance and condition of the engine I would have no doubt about that.

The problem I am having with it is this. It primes with 1 flip of the prop, starts right up and idles great. On the ground it transitions perfectly, once warmed up that is. However the first time I went to take off it hicupped a little between 1/2 to 2/3 throttle but the took off. Then after flying for a few minutes at a constant throttle it hicupped and died when I went to quickly transition. I got it down in one piece and leaned it out about 1/4 - 1/2 turn. She ran great for a couple of flights after that. I then went to test the vertical abbilities and she hicupped towards the top. And during the same flight hicupped again on a quick transition but didn't die either time. I am used to cars and in that case it is saying that it is too rich. Is this the same concept with planes? The thing that I am not getting is that it runs and transitions great while on the ground or a buddy holding it at any attitude but when she gets in the air it starts to hicup. Am I missing something here? I am affraid to lean it out too much in fear of destroying what appears to be a great performing engine.

Hello!
Well ! It sounds as if you have the idle needle screwd in to much!
When an engine is hard to start and everything else is correct then 99% of the time the idle is set too lean!
Try open it half a turn and see what happens!

Regards!
Jan K
Sweden

One thing you could check that no one else has mentioned, sometimes when installing the fuel tank the odd person gets a pinch in the fuel line right behind the firewall, it's easy to do.

I have 6 TT's. They all run great, including two .61's. Run TT46's on spad 3D's and practice my hovers, so you need a good reliable engine. The only problem I ever had with one was just recently. Was breaking in a brand new TT46 and after two tanks went flying. The bushing on the connecting rod got totally demolished, eaten away and out the ehaust. Got me stumped. Great hobbies here in Canada has great sevice and replaced the engine free of charge. The only thing that I can figure was that the bushing for some reason held on the crank shaft and turned within the connecting rod, eating itself to pieces. The engine looked brand new (it was) and was not over heated in any way. Anyway......... great engines and not the last one I buy.

Peter