inverted engine tank height question
 

HI, i almost have completed a older 1984 top flite red box kit called a top flite elder .20 , unlike what the plans call for
I've decided to canter the engine over , so its not totally inverted, with the cylinder at say a 8 oclock position
I've heard the more ya rotate a motor over, you basically raising the tank by a couple of inches
so where should the center of tank be located,, about level with the carb?
its a NIB O.S .25 FP going on plane with a airbleed carb , , Ive included a pic of the new top flite
Elder 40, showing the same engine placement as mine to give a idea as mines similiar
also i should mention, in the plans they show the engine totally inverted
curious more is they show a slant style tank, inverted also, with vent tube
facing downwards, wouldnt that just bubble up the fuel lol

RE: inverted engine tank height question
 

Centerline of the tank should be even with the spraybar in the carb, to about 3/8" below that.

RE: inverted engine tank height question
 

As shown in the picture, you cannot lower your fuel tank enough to have that engine run properly as mounted unless you use a device that will decouple your engine's carb from tank height issues. These devices are known as fuel pressure regulators and are sold by Cline and Iron Bay. They require that you pressurize your fuel tank with either crankcase pressure using a check valve and a crankcase tap (preferred), or muffler pressure using a check valve (not the best for a two-stroke engine). Bite the bullet and buy one of these two regulators and install it. Otherwise your experience will be one of misery. Do NOT buy the Perry pump in their place - just more miserable experiences.

RE: inverted engine tank height question
 

Actually, it would appear you could set the tank quite low. My experiance is that you can get away with the centerline slightly above the carb, especially on a TD. Also I have had good results with a Perry Pump, except that one lasted only a couple of years.

RE: inverted engine tank height question
 

Tony If the tank gets too high you have the siphoning effect which will flood the engine when not running. Nothing wrong with the 8 oclock position . The exhaust now goes down more (GOOD) The igniter is easier to put on. And it raises the carb a tad. The muffler will provide good presure. The center of the tank level or just a little below center of spray bar is good. Even if it is a slant tank it can be mounted any which way it is up as long as the vent tube is long enough to point straight up and touch top of tank.

RE: inverted engine tank height question
 

Where do you get the scale looking prop hub? I could use that on my Fokker. It's a .91 sized engine though.