Douglas Kupersmith's Comments

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At 3:55pm on August 28, 2019, Robert Riat said…

Thanks Douglas for responding.  I ordered aluminum fittings for the inboard end and will have them TIG welded in.

At 8:21pm on August 26, 2019, Robert Riat said…

Hi Douglas,  I saw your post from back in 2016 where you installed the return fuel line for your UL engine on the same end as your supply line.  I built a 750 with the UL engine and the fitting was on the outboard end of the tank and easy to plumb.  Now I am building a 650 and it will be much easier to plumb if I copy what you did.  I had heard some discussion that it was better to put the hot return fuel on the opposite end from supply to give it more time to cool.  Can’t think that is a problem, but wanted your opinion on how it has worked?

Thanks,  Robert inKansas

At 5:35pm on February 9, 2017, Theodor Galdi said…


Many thanks. I think I am going through the same process you set out in the last three sentences of your reply.

Since I don't know how to add an image to this comment, I am adding an image of the Composite Designs UL Power Panel  to my original post about the Kavilco cylinder head probes to see if the panel looks familiar to you.

At 10:59pm on February 8, 2017, Theodor Galdi said…


Here is what was behind my post to you:

There are all of these leads coming from the UL power ECU (see page 40 of the UL Power Installation DVD), some of which, I presume will be used by the Dynon.Then you have the Dynon EMS sensors some of which will have to rely on UL Power information. Finally you have the Composite Design UL Power panel and regular SP 2 panel.

What added to my confusion was--which I finally figured out--was the role of the Dynon oil pressure, oil temperature and fuel pressure sensors. I think I have figured out that those sensors are solely for Dynon use, and that UL Power has similar sensors that are controlled by the FADEC but are not accessible to Dynon

However, having understood (I think) the role of the Dynon sensors, I still do not have a way of figuring out how the fuel flow information from the UL Power ECU is sent to the Dynon. In Jon Croke's UL Power/Zenith 650 DVD, Gus Warren adds two red Dynon fuel flow sensors to the engine. Roger Dubbert says that those data are now available for use by Dynon . I don't know which of the two UL Power leads to connect to Dynon.

So, with this as background a few questions: Is there a preferred method of connecting the small diameter wires to each other?

2)On page 40 of the UL Power DVD is says to pull all five ground wires together. Does this mean they stay together, or are they distributed further. Do they go the the aircraft ground to to the Composite Design UL Power?

3)  "Pull all six positive wires together to a switch, install a 20 amp fuse and 14 ga wire?

Do these wires go to the Composite Design UL Power panel?

4) Is it possible to use Dynon wire lead to the oil temperature switch without a heat covering?

5) I presume the items in number 6 also  go to the Composite Design UL Power Panel.

As an aside, unlike Jon's DVD an the Zenith pdf. insructions, I think it would have been better to mount the voltage regulator on the firewall using using the same SCAT cooling ducting from the cylinder head baffles since the length of the alternator wires would allow this and the + and - wires would have been much shorter.

So, I am slowly figuring out these things, but thought I would let you know where I am.

Ted Galdi

At 1:22pm on February 6, 2017, Theodor Galdi said…


What sort of instrumentation are you using? I, as noted, have a UL Power 350 is for my Cruzer and am putting together a  Dynon Skyview panel.

What I am having trouble with it the interaction between the UL Power ECU and the Dynon EMS. There is an overlap in functions that I have not figured out how to wire.

At 5:58am on April 28, 2014, Larry Winger said…

Thanks, Douglas. With the lack of activity for over a year, I'm surprised that anyone is reading my Kitlog any more.  It feels good to be back in business and closing in on completion.  Larry

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