RPM and FF Question

[Janekom]

Yesterday we have done the first engine run and most things seems to be OK.
standard setup on a Lycoming IO-540 connected to an EMS D120.
We have seen 2750 RPM max (static) and I thought it should be about 2700. Did not have time to check everything, but the did check the Dynon setup - it is at 1.5 pulses. Then the travel on the CSU unit is also from stop to stop. Any ideas?
We also have the red cube fuel flow sender unit. The Dynon is set at 33000 (if I remember correctly) and I see in the documentation that for the red cube it might have to be 68000. Again - any thoughts on this one would be welcomed.

 

[Radomir]

I'd suggest 1 full turn on the forward set screw.. and set up max static to somewhere around 2,650-2,670 RPM.. You'll get some RPM as you pick up speed on takeoff roll... so setting static to 2,700 typically produces slight overspeed when you're airborne.

 

[Ron B.]

Before I would mess with adjusting the governor, and before first flight, I would get a optical tack and point it at the prop. There could be something with the Dynon. We have a Skyview and needed to add more resistors to get ours to read correctly. we used an optical tock to find our problem.
Ron

 

[RV10inOz]

On the point of resistors, you will need at least 100Kohm on the tach wire (close to the mag). Best to make up a sturdy piece and heat shrink it.

This prevents erratic readings. You will know if you have them. The resistor Dynon supply works fine on the other engines apparently but the 540's need at least 100K maybe a bit more.

DB

 

[Janekom]

CORRECTION!

We have seen 2750 RPM max (static) and I thought it should be about 2700.

I mean 2570, which is a tad too low.

What about the red cube and the factor for that?