lyk2fly

My Feedback: (3)

The only symptom left from a really hard crash is my vmax7 has a "miss"...for lack of a better word. It sounds just like a spark plug fired engine with an occasional miss. Under full throttle all is smooth. It is during the hovering throttle levels that it happens. It still flies ok but I just wonder what happened to cause it. In examining the engine (still on the heli) the only thing that I have found is that the metal venturi is slightly loose. I found this as I removed the air filter assembly. It will "spin" a small amount. Is this normal? Or am I looking in the wrong place for my problem? My old vmax6 venturi came completely loose from that engine. Anyway all you vmax7 owners....help!!!!
Mark

eegadsman

Hrmm..
The only problems I have with my Vmax7 is that it really really doesnt like it idle.. I generally have to set the heli down with a little 'extra' stick, just before hovering.. or it dies as soon as I stand back up. But it's always done that..

What percentage nitro are you using, etc?

I havent noticed my carb/venturi being loose, but then I've never taken off the screen that's on it.. guess I could check it for ya...

About the only the I can suggest, and I realize this is a DUH answer, but play with your needle valve a bit, and see if your running just a click or two too rich perhaps?

Also, change the glowplug.. seems to me like the vmax-7 plugs dont last very long.. I've had my 7 for about 4 months, and gone through 2 plugs allready.

lyk2fly

My Feedback: (3)

Thanks for the help......I did find the problem. It was "slop" in the throttle servo linkage. The slop was allowing the plunger in the muffler to move.....thus the irregular engine rpm that sounded like a skip or miss. A piece of fuel tubing tightened the slop. I forgot to mention that I strapped a pair of needle nose pliers to the landing gear (just goofing around). They weigh 5 oz. The heli lifted them with the 4 degree grips....I mean it flew! You could sure tell they were there but it flew high and far (not just a simple lift). I think that is pretty good. With the 6 degree grips I bet it would lift a lot more.
Mark

eegadsman

Good deal.. I've been concerned about my throttle linkage.. no the servo, but just the wire link that I have installed.. it hasnt interfered with anything yet, but it's caused the response to be somewhat slow at times.. i probably outta fix it before it becomes a problem, tho...