meps

My Feedback: (10)

I have a mk4 that has lately been flaming out when slowly advancing the throttle from idle to half stick position . It Belches and proceeds to throw a large flame before shutting itself down . I noticed that it normally does it when the humidity is relatively high . Has anyone else experienced this and if so, what did you do to fix it . I have a friend who use to own one of the large kingtechs that was doing the same thing . He was told to adjust something in his ecu due to high humidity and itfixed his prproblem . I don't think the wrens have that option . Any help would be greatly appreciated .
Thanks ,
Steve

joeflyer

My Feedback: (48)

Mine doesn't like hot humid weather either. You need to increase the ACCELERATION DELAY parameter, and you may also want to increase DECELERATION DELAY a bit. This will slow down the throttle response. I normally have both parameters set in the 15 - 20 range. During July and August I increase ACCELERATION DELAY to 45 - 50. You may have to go higher depending on the temperature and your engine.

I've learned to initially advance the throttle slowly on taxiing and takeoff when its hot out. Once the plane is moving and air is forced into the engine it's fine. Usually the only time I have an issue is taxiing back after a flight on a really hot day.

Also check to see that one of the tailcone bolts hasn't fallen out. If one of those bolts comes out it will bleed off combustion pressure and act that way even when its not hot out.

Joe

meps

My Feedback: (10)

Thanks Joe. I'll definitely try that tomorrow and will let you know the results .
Steve

meps

My Feedback: (10)

Joe, your recommendation works ! Thanks a million !
Steve

joeflyer

My Feedback: (48)

Great!
What value did you end up with for ACCELERATION DELAY?

meps

My Feedback: (10)

I put it at 45. I bought the engine from Ron Ballard over a year ago. He had it set at 20. Down here in NC it gets very humid.
Steve

joeflyer

My Feedback: (48)

You might notice a little bit of a delay in throttle response. When temps drop down into the 70's you can probably set it back to 20.

meps

My Feedback: (10)

I did notice more of a delay in throttle . I had to do a go around on one of my flights today and noticed it very quickly , lol.
Steve

brianw

I just got my engine back from Wren UK and flew it yesterday, it has the same hiccup between 0 and 50% throttle then cleans itself out. almost like it was being flooded with fuel. Any recommendations, its not very hot/humided in canada right now.
I was thinking the pump auto +2 setting but also dont know what increasing or decreasing the accell or decell delays do?
Thanks

joeflyer

My Feedback: (48)

Don't change the Pump Auto +2 setting. That affects fuel ramp up during start and has no affect on what you are experiencing.

I don't know your engine's history or how much time is on it. Acceleration Delay does exactly what the name implies; it delays the acceleration. The higher the number the more it delays. If it seems like it's getting too much fuel then try increasing Accel Delay in increments of 10 to see if that has an affect.

Good luck,
Joe

dmattmul

I am not sure if you are using V10 for the ECU but seems possible it gets "confused" especially after a air pocket goes through and flames out. Did not make much since but Xycoy confirmed that this could happen. When I get this problem i very very slowly advance the throttle to full one time. THen shut it down and refuel it and I can push the throttle up as fast as possible after that. The Xycoy needs to relearn the running conditons or so I was told.