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Wheels
07-18-2018, 09:59 PM
Called Dynon today to walk through the problem, Oil pressure in the Dynon reads dashes, not numbers. Dynon said configure the DS-10 for the sender on the engine, (Supplied by Rotax) but the panel still shows dashes, not numeric value. The technician on site took the 200 ohm resister out of the circuit on a hunch and voila, the number reads Zero. But
1.turning the prop by hand, top plugs out, no oil pressure indicated.
2. Turning with the starter no pressure indicated,
3. firing the engine up for 5 seconds, no pressure indicated.
4. Zero time engine, Purge complete, oil serviced to specs, oil present at the lifters, yet, no Dynon pressure. I should have stuck with steam gauges, on the Model IV, but hind sight is 20/20. Any ideas other than obviously running a direct pressure gauge in the cockpit and defeating the reason for this electronic whiz bang?

Dorsal
07-19-2018, 04:04 AM
First connect a temporary steam gauge to make sure the engine and sensor are working (I suspect they are). Can you post a diagram of how you have it wired? I can lend you a steam gauge if you need (went through something like this and still have the gauge).

Dorsal
07-19-2018, 04:10 AM
The unit can not work without the resistor, it is a voltage divider showing the ratio of the sensor vs the resistor. Do you have a decent multimeter? if so check the resistance of the sender (I believe that should be ~10ohms at 0 psi) and check the make sure the 200 ohm resistor is in fact 200 ohms. With the resistor in the circuit what is the voltage at the white wire?
Is this how you have it wired ?

Wheels
07-19-2018, 06:32 AM
Thanks Dorsal,
Yes, its wired like that. The power wire (red) reads 12 volts, the white wire reads 5 volts at zero pressure.
The P/N for the pressure sender o the engine is 456180.

Dorsal
07-19-2018, 09:36 AM
is that 5 volts with the resistor in place?

Wheels
07-19-2018, 09:53 AM
Good Question, I don't recall the tech telling me that. I'll call him. I see the part numbers are vastly different between you and I. I"m headed into the city, (we live in a rural area of North Idaho) I will try and find a UNF fitting for the lube pump and I"ll put a mechanical gauge on it to make sure we are ok there. thank you for your offer, I'll put a gauge in the tool box for the next guy in the neighborhood. I"ll check the parts book to make sure of the fitting and thread size.
What are you thinking about the resistor placement and voltage?

Slyfox
07-19-2018, 11:06 AM
Jay, a mechanical gauge would be a real good idea at this point. as far as the sensor you have with the dynon, maybe you should inject air pressure into the sensor to see if it will read. If it does read than you might have air in the oil system on the engine and you will have to get that out. the best way is to inject air pressure into the vent on the tank while cranking the engine(make sure the tank is sealed with the cap on). I generally use a free flowing air blower and limit how much I pull the trigger. Don't run that engine until you know you have oil pressure. you could just leave the sensor out and see if it shoots oil out when you crank the engine, that will tell you real quick if you have pressure or not.

the most important thing is to know your engine is making oil pressure. hope this helps.

Wheels
07-19-2018, 01:03 PM
I just ordered a lube pressure test kit with the right nipple and a gauge. I also ordered the Kavlico oil sender to replace the one that came with the engine. The Dynon install manual recognizes the part number but it also said that they use a Kavlico sensor. I figure if they use it for the Dynon, it's probably what they actually have success with. I"ll check back with you in a few days when I get the parts. I hope after everything is up and running with a smooth pitch and a full RPM at static, that it starts to rain and hail with 40 degree crosswinds over my runway. Then and only then will I believe that I have arrived.

Dorsal
07-19-2018, 04:24 PM
Sounds like a plan, FWIW I also use the Kavlico.

cap01
07-19-2018, 11:30 PM
i was unable to use that fancy oil pressure transmitter that came with the engine as it wasn't compatible with the grand rapids eis . had to install the old vdo xmitter.

Wheels
07-23-2018, 09:51 PM
I installed the test kit gauge.
I did an engine purge procedure by the book.
I got pressure on the gauge in a few turns of the prop.
I completed the purge, checked the valve tappet clearance and buttoned up the engine.
Tomorrow will do a test start with the direct pressure gauge in place. Will do run up and leak check. The Mechanic will sign off the engine and a/c inspection if all goes well. I'll let you know

AirFox
07-24-2018, 06:50 AM
Awesome Jay! Congratulations on a challenging engine upgrade. I have no doubt you will love that plane.

Scott

DesertFox4
07-24-2018, 04:26 PM
Real good news Jay. Oil presure always a good thing.:)

Wheels
07-31-2018, 10:32 PM
Ok, All is going well, I have about 7 hours on the engine and the numbers and temps are settling down to a very normal range.
There was some learning curve going on with just reading the gauge but I think I have it. Not sure if I'm reading the water temp right, but its around 201 most of the time. I need to open the book before my next flight to make sure I have defined the parameters right as 200 is showing yellow and the 912 is going to be at 180 or higher most of the time. I don't think yellow is right.

I made my first real flight mission today and flew the 30 miles to Sandpoint Idaho to replace my broken phone with a new one at the Verizon wireless store. Wife would not sit that one out so we flew in 90 degree heat and landed in 10+mph 90 degree cross wind on asphalt. It wasn't real pretty but it was safe.

All temps in the green,( except water) VNE at 5460 in the smooth part of the ride. No leaks, just fun.

Dorsal
08-01-2018, 03:23 AM
My CHT (water) temp runs consistently around 200, I think I have yellow set to 215.