Hi,
Well I have a waco bi-plane and its a smaller plane so I have a magnum xl .28 on it right now and i have it mounted upside down and a little to the left at a slant and the gas tank is in the right side up. I cant seem to keep it running it dosnt pump the fuel thru the line if i cover the muffler and it pumps fine and I have put a check valve on it and that gives to much pressure. I have a .40 motor and im thinking about putting that on there but that may be to much. I have also put a baffle in the muffler and that didnt do it as well.
If anyone can help that would be sweet!!!



KEP HER IN THE AIR!!!!!!!!

May want to try a glow plug with an idle bar and lean it out a little on the low side. 2 strokes don't like to be inverted and can be a little tempermental. The case will load up on fuel and cause them to flood easily.

you put a check valve on it where???? in the line between the muffler and the tank??? if so remove it

Definitely remove the check valve.

My first thoughts reading through this is that there may be issues with the tank. You'll need to figure out if the tank is set up properly. Look at the diagrams attached and double check that your tank is setup in the same manner. Also, you will need to check the tank position in relation to the carb of the engine. The neck of the tank needs to be approximately at the same level as the carburetor of the engine.

Note on the diagram. The stiff tubing shown in the tank isn't necessary, but in my experience it helps to keep the clunk from going forward and getting stuck in the tank.

Ken

In addition to RCKen's advice, check the actual fuel flow.

Make sure that it travels FREELY...

Connect a piece of CLEAN tubing to a small bit of brass tube and use this to blow into the tank pressure intake.

Do this with the output tubing from the tank over a receptacle..

Just a little bit of pressure from you should result in ample flow... also make sure that your lines are as short as possible.

It sounds like there might be too much restriction to fuel flow...

THE GUY AT MY HOBBIE STOR TOLD ME TO DO THE CHECK VALVE BETWEEN THE MUFFLER AND TANK. I WONT PUT IT ON THERE ANYMORE i TOOK IT OFF CUZ OF ALL THE PRESURE. IM NOT SUR I KNOW WHAT A GLOW PLUG IS WITH A IDLE BAR? I WILL MOVE THE TANK A BIT TO SEE IF THAT HELPS AND THE FUEL DOES FLOW FREELY WHEN I BLOW ON IT. THANKS FOR ALL THE HELP.

PS SORRY ABOUT THE CAPS JUST SAW IT WAS ON. LOL.

You should NOT need an idle bar nor to move the tank at all.

Check valves typically produce too MUCH pressure as there is no pressure relief.

But you DO need ample and free fuel flow to the carb.

Too long of a fuel line, or other resitrictions can prevent fuel from flowing freely.

Here is an example of an idle bar plug
http://www3.omnimodels.com/cgi-bin/w...I=FOXG1470&P=0
The idle bar is supposed to keep big drops of fuel from splashing on the glowing element.

<< Edited to add text below >>
I have no idea if an idle bar plug will help your engine run better. I am thinking "No" since you're having fuel draw problems. The idle bar would be more likely to help if you were getting too much fuel at idle.

Getting the tank height "pretty close" to optimum and making sure you have proper flow is probably the best approach.

yeah... remove the check valve. i'd return it to the hobby store owner and complain because i think he really didn't give you good advice.

then i'd check the tubes. i wouldn't be surprised if you had an air leak somewhere and that's why you're not getting any fuel.

if it still doesn't run, maybe remove the top wing, turn it over on a stand and start it up right side up. see if that works. a little unconventional but at least you know if maybe it's the engine that's not running right.

upside down engines generally flood. i'm surprised that yours is starving for fuel.

I believe his engine is NOT inverted, it is mounted with the head at a downward angle to one side instead.


I run most of my engines inverted, and all I do is replace the regular glow plug with a "long" plug to keep the element from fouling with fuel.

I've tried IDLE bar plugs ad-nauseum, but I get much better results with long plugs instead.