Genrally speaking, how much run time should I get per ounce of fuel on a ST3000?

Thanks

Loopman

It seems to me that when I started running them several years ago, I got 10 minutes from a 16 oz tank. Now I run at least a 20 oz, and preferrably a 24 oz.

I get around 15 minutes on a 20oz tank. Ed is right go with the 24oz if possible. That is what I am putting in my new PT-19.

I had an ST3000 in a quarter scale Fleet biplane, used an APC 20 X 10 prop. The engine will swing this big prop just as happy as a clam and the idle was wonderfully slow. My St3000's were wonderful engines, very easy starts, ran great on 12% lube 5% nitro fuel. I used the standard ST carb with decent size lines and a Perry crankcase pressure actuated pump, and never had a problem. I would use as much as 2 oz of fuel per minute depending on how much throttle I would use. I had a 24 oz tank, and after 10 minutes of flight I had better start getting her down before it ran out of fuel. I think the large prop increased my fuel consumption, so 2 oz a minute may be a little high for props in the 18 inch range.

I will use a 24 oz tank after hearing y'alls recommendations. I do have a perry pump but will have to drill a pressure tap and an access hole in the back of the bell mount. How do you adjust these pumps if you don't mind me asking?

Happy Flying!


LOOPMAN

Loopman,
I used a Perry osillating pump that way I did not have to drill the crankcase. Also I use a 18X10 prop. What are you going to put this on? Cubfan

Cubman,
The Super Tigre's going on a Northwest Hobby Technologies Corsair. I was contemplating using gas but I want to keep overall weight below 17 lbs. The pump I have requires a pressure line and it's no big deal to drill the backplate for a pressure fitting.

Cheers!

LOOPMAN

You adjust the pump via the small brass screw in the end of the thing. If my memory serves me correctly you turn it out to lean and inward to richen. In another words backwards from what you would think. I had this combo in a 1/4 scale extra and it ran very well. Probably one of the easiest starting engines I have owned once I got it tuned in correctly. I had a 20 ounce tank and was getting around 10 min. flights. Hope this helps!

What fuel do you run in the st3000......I plan to mix....I understand they do not like castor or a lot of nitro...
comments welcome
5x5

ST 3000, and all Super Tigres, seem to take a very long time to break-in. I usually run mine rich on the bench for about a gallon of regular fuel. Then I fly with regular fuel for another gallon before switching to a low oil fuel. The Omega Super T fuel is about 12% oil and 10% nitro. 5% works OK, too.

Run your engine where it leaves a smoke trail at the first of the flight. It should lose the trail by half tank. If you run them like this, they'll last nearly forever. You should only have to re-set your needle valve if the humidity goes way up, like a foggy day. I usually just accept a slightly rich run. I mean, the needle should stay set for years! Get it right and don't mess with it.

I like an 18-10 prop. The 3000 will turn a 20-10, but the needle gets critical, at least on mine. I have had 6 of them, 1-2500, 4-3000 & 1-3250. The 20-10 works on the 3250. The 3000 & 3250 get max hp at 7900 rpm, so prop for 6800-7200 on the ground. It is a lugger.

It should also start in 1 flip, 2 max.

Thanks Ed,
I am bookmarking you so I can ask more later.....You are very helpful..
Regards
5x5
Daniel

Thanks for all the info guys. I bought a case of Powermaster 15% Nitro/18% oil at the Perry show. I called my local propane service and they are going to sell me some methanol. I plan on cutting the Powermaster fuel 50/50 with the methanol and that should give me 7.5% nitro and 9% oil. That should work. The ST3000 is already broken in so I should have no problem with the lower oil content.

Thanks

Loopman

Loopman,
Be careful with only a 9% oil content. I personally will not run below 12% oil content. I homebrew my own ST fuel. The recipe that I use is 20oz oil, 6oz. nitro, 102oz of methanol. This gives you a 15% oil content and a 5% nitro content. I use Klotz Techniplate synthetic for methanol. You can get the Klotz from Sig. The St will run well on no nitro just cut the oil back about 2oz
Cubfan

Lots of good information listed but my experience with about 4 of the ST3000/3250 size engines is overheating which leads to lose of power and if you do not land soon the engine stops. I cannot get it to run rich enough to prevent the above weather the engine is cowled or not. I realize that I have not listed any where near all the info that would be needed to diagnose a problem but has anyone experienced any situations similar or have suggestions of possible causes or solutions. Thanks

What size fuel line are you running? It sounds like high-speed fuel starvation. I had this same problem until I switched from medium to large fuel lines and replumbed the fuel tank to accept larger brass tubing (don't forget to drill out the clunk too).

I personally never ran a fuel pump, but opted instead for a main tank (on the CofG) and a header tank under the cowl. It started easy, ran great and kept the same needle settings from the start of a flight to the end. I also always ran it with a fuel and air filter (and after-ran after every flying session), so the piston/sleeve is still as smooth as day one (some carbon build up, of course), without any scoring.

Daren