anonymouse

I have a BT-32 in my 1/4 Rearwin and have about 20 flights over a period of two years. The engine, other than being a bit hard to start by hand runs fairly smooth and has adequate power for the installation. The engine is relaible and has never quit or stalled. The first flight this season exposed a problem that I cannot come up with a reason for, nor a solutiion to. I did my normal engine off range check and radio was fine. Fired up and took off, and set up for a trim pass and had violent flutter in both elevator and rudder with a bit of surging in engine RPM. Throttled back to idle and made an emergency landing without incident. On performing a range check with engine running and antenna collapsed I could only get about 30 FEET away before getting flutter in all control surfaces and surging in throttle, obvious interferance......Here is a list of the things done to trouble shoot. 1. Checked all metal to metal contacts for tightness (no rubbing or chattering). 2. Changed crystal in reciever. 3. changed recievers (on same channel). 4. Changed frequency with new crystal and different transmitter. 5. Changed plug. 6. Wrapped plug lead with foil. 7. Made sure no wires (kill switch) ran near reciever or antenna. 8. Checked battery for possible problems, found none. 9. Bypassed switch ( plugged battery directly to reciever). 10. Disconnected kill wire from mag (ground). 11. Disconnected servo leads one by one and did range check each time. This problem has ocurred at three seperate locations so interferance from an out side source is pretty much ruled out. Engine RPM makes no difference in my mind. I am at a total loss as to what is causing what seems to be engine generated electrical noise... HELP ME ..HELP ME....Short of buying a new engine whata I does to fix it?????? I've kissed a pig and whistled Dixe and neither helped!!!! Mouse NEW QUESTION: IN REFERENCE TO 9. Engine kill switch is located just below radio on-off switch, , big NO NO or no big deal?

Bax

My Feedback: (11)

All of the radio components should be routed as far away from the engine and ignition wiring as practical. If you're getting ignition noise all of a sudden, it could be a bad plug wire, a bag ignition unit, a bad spark plug, or even a bad component in the radio system. Everything needs to be checked carefully. Try a new spark plug first. It could have a crack in its shielding that's allowing electrical noise to get out.

anonymouse

Mr BAxter, Thanks for the reply. The first thing I did as spelled out in my 1st post, was to eliminate the reciever and radio possibilities. I replaced the spark plug, and made sure ALL mounting hardware at engine, bolts screws etc were tight. Tried wrapping coil wire with foil. This problem started SUDDENLY, with no warning glitches , etc. I am leaning towards a faulty ignition unit. Is there any way to verify other than unit replacment?

Bax

My Feedback: (11)

If the ignition unit is bad, it needs to be replaced. No way around that. The only way to test is to try a new one. If you send the engine here, we can check it for you.

anonymouse

After a month of diddling with this problem I got a suggestion from an R/Cer in England who had the same problem, and using his suggestion I cured the problem... Fuji could, if they wanted to,, keep this from happening in the future, by changing spark plug lead to a shielded lead grounded to the engine. That is what cured my problem and the price was minimual.....