I have one of the older versions of this engine. I have finally found time to play with it but, it isn't working like it use to. Everytime I turn over the propellor trying to start it, it acts like it wants to run but it stops and backfires[:'(]. At first I noticed the pressure nipple was leaking so I put some glue on it to seal it, but it still isn't working[X(]. Also, is there suppose to be air or gasoline going through the pressure nipple? Sometimes I saw gasoline running throught the tube but now I just see air or nothing. Guys please help me because I really want to fly this airplane before it gets too cold.[&o]

Bookie,


If you mean the pressure nipple, that is screwed into the right-front side of the crankcase and connected by a flexible tube to the nipple, in the bottom part of the carburettor, on the opposite side from the needles; it operates the carburettor's diaphragm pump.
It is supposed to be sealed by a fiber washer; not with glue.

It provides pressure/vacuum pulses, of mostly gaseous medium, but an occasional drop of gasoline may get there too, from the crankcase. If gasoline appears to flow into the tube from the carburettor, the pump-diaphragm could be leaking.

Could the ignition sensor have moved, changing the initial ignition advance of the engine, causing it to back-fire?

You did not state how old the engine was. Is it pre-red-head, or early red-head? Does it have the film canister ignition, or the flat package Vlach? Single or double magnet?

The pressure line should be void of fuel.

Check your ignition timing. It should fire in top dead centre(Vlach) , or just slightly before that. The film can ignition should fire 15 degrees before dead centre. The sensor must just cover the magnet, and should have the longest part to the magnet collar, without being twisted out of that orientation. The gap between sensor and magnet should not exceed 0.6mm (.025"). Check voltage on the ignition terminals. It should at all times be more than 4.5 volts. Set spark plug gap to .020" (0.5 - 0.6mm)
If all is right, and the engine still backfires, have your ignition checked by your dealer, or replace it with a new one. Depending on engine age, you may have to replace the prop drive washer.

Well I think that the problem is that I have a short in the wiring to the ignition coil. Only because sometimes the ignition coil fires and sometimes it doesn't. Oh and I have the before red-head version of an engine with film canister engine and single magnet. Do you guys know the possible estimates of fixing the ignition coil? I am an electrician but I cannot seem to get the canister open. Thanks for the endless help guys![&:]

Your engine probably has a B- stamped in the engine mounting lug, maybe C, meaning it is 2001 or 2002 vintage. The canister is crimped shut, but can be pried open. These ignitions were very sweet running, but lacked many of the current voltage surge protections. This made them prone to failure when operated without proper spark ground.
I would suggest replacing it with the modern two magnet Vlach ignition. The prop drive washer needs to be replaced as well.

Thanks. How much would all of this cost? Because I bought the engine for a used price and have flown it a few times. THe new version of the engine sounds great but the prices aren't[&o] what I'm looking for right now.

The engine is worth the effort, and when well run in, has the same power level as current engines.
mail me for parts through my website if you want to restore the function.