ZDZ 80 Tuning

[moose]

Need your help guys....I have had a trouble free ZDZ 80 since I got it but after a dead stick landing ( due to running out of fuel ) and getting the firewall ripped out of place.....I have finally repaired all and seem to be having some trouble tuning the engine.

I know this sounds really silly but I have also forgotten which needle is L and which is H ( want to try to avoid removing the the prop and cowl ).

Since my repair nearly all my landings have been dead stick !!.....getting really good at those !!

I am using a bambula 26/10 prop and still using mineral oil.......just about getting to 4 gallons.

What rpm are we looking at for the idle and max settings....how should I go about getting an even mid range.......just tell me what ya got.

Thanks in advance guys !!

[Jaybird]

If it has the walbro carb, the low end needle is closest to the engine, towards the front of the plane. Try them at about 1.5 turns out from closed, that should get you started.
Brian

[Boulder]

First, the low speed is the screw closest to the motor and the" hi" is towards the carb intake.

To be honest I don't know where my settings are, but my idle is 1500 to 1600 rpm and my top speed is currently 7200 with a 24 x 8 Bolly CF prop. I know that hi speed runs me out of the best power range, I just won't be running full speed until my new props get here.

With my Menz 26 x 10 I ran between 6200 and 6300 rpm.

I'm going to guess your running too lean and your motor is getting hot. With any 26 x 10, unless it's the narrow Menz Ultra, you shouldn't be getting over 6300. If you're getting some mid-range burble, I've been told that's normal. Mine is tuned so low and hi are smooth with a smooth transition, and I live with the little burble in the mid-range

[moose]

Well I'm getting a pretty stable idle at 1250 and a max of 5700....but then i richen it a bit to run at 5400rpm......is that to low ?

I am using the recommended prop ( RCS recommends this prop for break in ) which is a 26x10

Thanks for your quick replies guys!!

[plaster93]

I have a zdz80 also,does anyone know how to sweetin up the midrange?My hi and low are good but the mid range is laggy and when your doing rollers and such its hard doingit at the top end of the throttle. Does adjusting the timing help at all? I know its at 7mm but if I move it closer will that make a difference?

[Boulder]

I haven't tried the timing, but if I'm not mistaken, ZDZ recommends 6mm at TDC.

[madmax]

Plaster, the best advice I can give anyone on the 80 is to CUT THE TIPS! On the muffler that is... Knock about 1/4" off the tip of the mufflers with a dremmel tool. You will absolutely notice an incredible amount of midrange power. Doo it!

[Boulder]

	Quote: Originally Posted by MadMax
	Plaster, the best advice I can give anyone on the 80 is to CUT THE TIPS! On the muffler that is... Knock about 1/4" off the tip of the mufflers with a dremmel tool. You will absolutely notice an incredible amount of midrange power. Doo it!

Maxie,

Why in the hell didn't you tell me that earlier!!!! I've been living with "just enough power" in my Yak for weeks now...

[moose]

Max, are you referring to the supersonic muffler.....cutting off both tips ?........If it don't work you owe me one

[madmax]

On the pitts muffler, you will notice that the tips come inwards and restrict the flow.. If you lop off 1/4" off the bottom, you will start to see the motor come alive. This is an incredibly common, and age old mod for these motors. If you don't like it, my name isn't colonel sanders.

[Jaybird]

	Quote: Originally Posted by plaster93
	I have a zdz80 also,does anyone know how to sweetin up the midrange?My hi and low are good but the mid range is laggy and when your doing rollers and such its hard doingit at the top end of the throttle. Does adjusting the timing help at all? I know its at 7mm but if I move it closer will that make a difference?

I have the same midrange burble. It transitions really well but the sound just aggravates me. I had it adjusted out but the motor had no power so now I just live with it. I have wondered about adjusting the timing but was afraid to fool with it.

[ilovemetro]

	Quote: Originally Posted by moose
	Need your help guys....I have had a trouble free ZDZ 80 since I got it but after a dead stick landing ( due to running out of fuel ) and getting the firewall ripped out of place.....I have finally repaired all and seem to be having some trouble tuning the engine. I know this sounds really silly but I have also forgotten which needle is L and which is H ( want to try to avoid removing the the prop and cowl ). Since my repair nearly all my landings have been dead stick !!.....getting really good at those !! I am using a bambula 26/10 prop and still using mineral oil.......just about getting to 4 gallons. What rpm are we looking at for the idle and max settings....how should I go about getting an even mid range.......just tell me what ya got. Thanks in advance guys !!

what size tank you using? me and my dad are running a 32 oz i think and we fly for about 12 mins and only use 1/4 of the tank... you must have been flying a long time or something isnt tuned right, on yours or maybe even ours.