aps f4u

This is my second Supr Tigre 4500. The first one that I had ran great, though I didn't have it very long before I sold it. This one however is having trouble when I idle for a while then go to full throttle, it wants to puke out on me. I have heard of putting four stroke plugs in these larger two strokes to help them idle a little better? I didn't know if this would help, or if it is even my problem. I seem to be getting good fuel travel and no air bubbles in the lines, I am running a bisson pitts muffler and a 20x10 as called for. This 4500 is on it's fith tank of fuel and I never ran in to trouble like this with my other one. Any of you guys out there with these 4500's please give me some feed back on how you get your 4500's to run tip top. My engine didn't come with a manual, so from what I can remeber from the last one is, you run them with alot of oil content, then after break in, you run lower nitro and oil such as 5%-10%, if I remeber right? I t has been a while since the last one. I am running 10%nitro with 17% oil.please correct me if I am wrong on any of this. Your info is kindly appreciated. Thanks

A

DarZeelon

Corsair,


I believe these engines need less, much less oil than what you are using, for general running.
Only during break-in do you need higher oil contents.


From the manual for the ST 3250:
------------------
High Quality Fuel: During the break-in process, your large
SuperTigre engine requires fuel with a minimum of 15% oil
content by volume. The exact type of oil is not critical...it can
be all-synthetic, all-Castor, or Castor/synthetic blend, but do not
go below a 15% oil content. If the oil content of the fuel
cannot be determined, use a quality 2-stroke fuel with a
nitromethane content of 5%-10%. The break-in fuel must be
used until the engine is well broken-in. Since an engine will
break-in over the first few gallons of fuel, run your engine on
the 15% oil fuel for at least two gallons worth.
After the engine is broken-in with 2 gallons of fuel containing
15% oil, you can use a fuel that has as low as 10% to 12%
oil content by volume. The oil can be all-Castor, all-synthetic,
or a Castor/synthetic blend. Many fuels blended as “Super-T”,
“S.T.” or “SuperTigre” fuels are fuels with low oil content. Be
careful in selecting your fuel. Some fuels contain less than
10% oil. You must be careful setting the high-speed needle
when you use fuels with low oil content, because there is less
margin for error if you get a slightly-lean run. Nitromethane
content can be 5% to 10%, but 15% can be used if attention
is paid to the high-speed needle setting so that the engine
will not detonate.
Do not use fuel with low oil content for break-in running!
If you use a fuel with low oil content for break-in running,
there’s a good chance that the connecting rod will seize to the
crankshaft from lack of sufficient lubrication. This will almost
always require replacement of the connecting rod and
crankshaft, which is not a warranty repair.
-----------------------------------------------

Please contact your local dealer for the fuel your ST 4500 will like best.

I believe Tower sells special fuel for large Super-Tigre engines.

aps f4u

Thank you much Dar!!! This helps me out alot. This is my first WWII giant scale(TF P-47) build that this is going in, so I want to get this running right and hopefuly no problems occur!!I knew that you had to run high oil content to break in, just wasn't for sure what to go with for fuel once it is broke in. Thanks again.

f4u

jaka

Hi!
I think you use too much nitro, try 5%!
Regards!
Jan K
Sweden

KEITHW

My Feedback: (2)

I run 10% Klotz,no nitro and use an O.S. #8 plug. For inverted use an O.S. #F plug. I do this for all my big Tigres From the S2000 to the S4500.

Good luck

Keith

aps f4u

Hey KEITHW, I will be running this in a TF GS P-47 Thunderbolt and it will be inverted, so a O.S. #F plug will do the trick? and of corse less oil and nitro. I have heard this before of running a four stroke plug in these bigger two strokes, but wasn't sure. Also, what kind of pitts muffler are you using and did you plugg one of the exhaust stacks? I was told once that if using the Bisson pitts muffler, to plug one of the exhaust stacks for better back pressure?
Thanks for the feed back

a

KEITHW

My Feedback: (2)

f4u
I am using one of my 4500's on a giant Midwest Sweet and Low. I have a Bisson Pitts muffler on it. I don't have any of the outlets plugged off and it runs great!

Good luck

Keith

Cuzlikedam

My Feedback: (22)

there are a number of "tricks" to try.
of course large fuel tubing from the tank all the way to the carb.
use a f type glow plug
plug one hole off in the muff ( not always necessary)
use 0- 10 % nitro and atleast 17% oil content
make sure there are no air leaks anywheres. check around the carb and make sure muffler is tight
and if all that doesn't work then take the carb off flip it upside down, see where the cats eye is located, and losen up the spray bar and rotate it ever so slightly either to the front or back. this stops the carb from spitting to much fuel strait in the motor and flooding it. i run nothing but super tigres and have for years and never had a problem. just take your time and be persistant . thanks David