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Have things to tweak and I need a lot more landing practice.
Congratulations on your completion and first flight from a 750 scratch builder with a Viking. I want to talk to you about your cold weather start technique.
Jerry in WI
It's pretty basic, 1-have well charged batteries and 2- cycle the master switch off & on a few times to prime the injectors before starting. Some times I have to do the switch cycling a couple times.
Thanks for the info Tom, I have tried to 2 cycle the Ecu switch a few times, and have not had much success yet. Perhaps more than twice is needed. My engine is the most hard starting thing I have ever encountered. I am within a couple of days from requesting my Airworthiness inspection and sure would like to figure out how to get the engine started more easily. My Batteries are well charged and sometimes I have to crank/cycle/crank more than 30 seconds to get a start. During cranking, I get several "kickbacks on the starter due to over advanced timing. Do you see any kick backs on your engine??
When I first got my engine I was giving it too much throttle and was getting back-firing and kick-backs.
I talked with Jan a couple times and tried his suggestions but was still having trouble. He actually flew here (NC) from Florida and checked the engine out (it would start on the first time when he was here) but he did a little "tweaking" of the ECU and it's been reasonably easy to start since then.
My most difficult starting was with 14 deg. of pitch on the prop, it's now at 12 deg. and starting better. At 12 deg. pitch I still get good climb and the engine will run up to 5900 rpm at climb. See attached Screenshot.
Thanks again Tom for the info. I have been giving no throttle, leaving it at the idle position,(16-1700) rpm when it does start. The kickback issue is visible on the "turbo" post at the Zenith factory video at the 15.5 minute mark when Jan was flying the turbo with Sebastian. Do you know if he tweaked the fuel ratio or the timing at start? Perhaps I will try an electronic manual primer to see if I can match the fuel needed while cranking. The chances of Viking flying to
WI to help me out are probably pretty slim so I'm most likely on my own here. I'll bet that you and I are not the only ones that have had problems with cold weather starting.
The engine runs well once it starts. 12 degrees of prop is the recommended pitch for a 750, It would seem that your first setting of 14 deg. would more suit a 650.
I'm not certain what changes Jan made to my ECU, he did mention increasing fuel on starting.
I doubt you could expect a trip to Wisconsin but I'm sure he is dedicated to getting all Viking owners satisfied with the product. Just keep calling Jan about your problem, I even mailed my ECU back to Viking for checking. (guess they could put the test engine in a freezer).
Sure hope you get yours starting soon. The weather in NC has been ratty lately so no test time.