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First Engine run

Dave -

Congratulations on your progress ... looks like you will be in the air very soon.

Wishing a you a fun and exciting ... but uneventful first flight.

Happy Flying,
 
Try to keep the rpm's between 2000 and 2500 during warm up, the gear box needs the load from the prop to not prematurely wear out the dogs and bellville washers in it and cause a premature rebuild.

Maybe read the Rotax engine owners manual, for more details.


Beautiful new bird, get all the boxes checked off and signed off and you'll be airborne very soon.
 
Just following the checklist.

This is the checklist that I used from VAN'S POH for the RV-12iS.
It was telling me to start the engine with a Throttle Position ? 50% +/-5%. That is exact what I did.

It took me about 7 sec to read through the check list from when I started it at 50% throttle position to get to reduce power to 2500 to let the oil warm up.

Then I waited for the oil to warm up took about 6-7 min, then did the runs at 4000 RPM.

Just following the checklist.



4.5 ENGINE START
CAUTION
Do not start engine when oil temp is below -13? F / -20 ? C or ambient temp above 120 ? F / 50 ? C
 Brakes ? TEST & HOLD
 Fuel Pump 1 Switch (912 iS Only) ? ON
 Lane A & B (or Ignition Switches) ? BOTH ON
 Lane A& B Fault Indicator Lights (912 iS Only) ? Illuminate and extinguish after 3 seconds
 (If, after 3 seconds, a light flashes, illuminates, or fails to illuminate, abort start and refer to 3.2.1 ?Lane Fault Indications?)
 Fuel Pressure ? CHECK above 43.5 psi (3 bar)
Throttle Position ? 50% +/-5%
 Propeller ? CLEAR
 Ignition Key ? ENGAGE (until RPM > 1,500 RPM) (10 second max activation followed by 2 minute cooling period)
 Throttle ? REDUCE as required.
 Oil pressure ? CHECK 12 psi within 10 seconds or shutdown engine
 Throttle (912 iS Only) ? Above 2,500 RPM for 5 seconds.
 Engine Gauges (912 iS Only) ? CHECK SHIFT GEN B to GEN A
 Ammeter ? CHARGING
 Avionics Switch ? ON
 Fuel Pump 2 Switch (912 iS Only) ? ON
Throttle =< 2,500 RPM until oil reaches 120 F (50 C)
 
There was a post by RV2002builder about why the less than 2500 rpm when the oil temperature is below 120F.

The oil pump sucks oil from the sump tank. At lower oil temperatures, when the oil is high in viscosity from being cold, if the rpms are too high, it can cause oil pump cavitation.

Nice to know the logic behind the engine warm up and restricted rpm range.
 
This is the checklist that I used from VAN'S POH for the RV-12iS.
It was telling me to start the engine with a Throttle Position – 50% +/-5%. That is exact what I did.

It took me about 7 sec to read through the check list from when I started it at 50% throttle position to get to reduce power to 2500 to let the oil warm up.

Then I waited for the oil to warm up took about 6-7 min, then did the runs at 4000 RPM.

Just following the checklist.



4.5 ENGINE START
CAUTION
Do not start engine when oil temp is below -13º F / -20 º C or ambient temp above 120 º F / 50 º C
 Brakes – TEST & HOLD
 Fuel Pump 1 Switch (912 iS Only) – ON
 Lane A & B (or Ignition Switches) – BOTH ON
 Lane A& B Fault Indicator Lights (912 iS Only) – Illuminate and extinguish after 3 seconds
 (If, after 3 seconds, a light flashes, illuminates, or fails to illuminate, abort start and refer to 3.2.1 “Lane Fault Indications”)
 Fuel Pressure – CHECK above 43.5 psi (3 bar)
Throttle Position – 50% +/-5%
 Propeller – CLEAR
 Ignition Key – ENGAGE (until RPM > 1,500 RPM) (10 second max activation followed by 2 minute cooling period)
 Throttle – REDUCE as required.
 Oil pressure – CHECK 12 psi within 10 seconds or shutdown engine
Throttle (912 iS Only) – Above 2,500 RPM for 5 seconds.
 Engine Gauges (912 iS Only) – CHECK SHIFT GEN B to GEN A
 Ammeter – CHARGING
 Avionics Switch – ON
 Fuel Pump 2 Switch (912 iS Only) – ON
Throttle =< 2,500 RPM until oil reaches 120 F (50 C)

There was a post by RV2002builder about why the less than 2500 rpm when the oil temperature is below 120F.

The oil pump sucks oil from the sump tank. At lower oil temperatures, when the oil is high in viscosity from being cold, if the rpms are too high, it can cause oil pump cavitation.

Nice to know the logic behind the engine warm up and restricted rpm range.
That is correct, but to automatically apply what is known about one model of engine to another model of engine is not good. As you regularly (and correctly) recommend.... follow Rotax's recommendations/documentation.
As can be seen from the excerpt from the manual, that is what he did.

The 912iS has many differences from the ULS.
One of the major ones is its power generation system.
It actually has 2 built in alternators. One is dedicated to generating power that is exclusively supplied to the engine, the second is used to power aircraft systems.
Without going into deep detail of how it all works I will keep it simple by saying that the engine systems have control over how the power distribution is switched. After engine start, the engine RPM is purposely raised to ~2800 for a few seconds which makes the engine system switch the secondary alternator output over to providing power for the aircraft bus. after seeing the amp meter indicator switch to showing a positive rate of charge, the RPM is reduced to 2500 or less for the remainder of the warm up.

So David probably did do exactly what he was supposed to do (though I confess I didn't watch teh video so don't know for sure)..

BTW, Rotax specifies using 50% throttle for starts. We have found that to be good for most cold starts, but we use 35% for a warm engine. It starts nicely without revving up so high. After the start we push the throttle up just enough to get the alternator on line and then pull it back again for warm up.
 
New RV12is

Good job David, I believe you will enjoy the 12 very much, I knowI do! N40Bf yes I am a legend. Ha! HA! BTW the Rotex IRMT two day school was a great help to me. GL Ben
 
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