how can I tell if my 912uls has softstart built in

by Norman Pfaff in 912 / 914 Technical Questions 12 years ago

how can I tell if my 912uls has softstart built in an if it does, do I have to do anything to activate it? Also is there any special start procedure?

Re: how can I tell if my 912uls has softstart built in

by bill martin » 12 years ago

bill martin

10 757 0

Norman,

If you have softstart, your engine will run at a lower speed and sound differently for 5 to 10 seconds after starting. The difference is quite noticable because the engine is firing at very close to top dead center. After the softstart time elapses, the spark will automatically advance to its normal setting with no throttle input from you. To start, set the throttle at full idle and the choke full on. Roger can probably supply you with the serial numbers of the engines with factory installed softstart. You can also open the installation manual under he SUPPORT tab and check the wiring diagram. The extra wire that actuates the softstart will be wired in somewhere bwtween the start switch and the starter solenoid spade connector.

Bill.

Thank you said by: Norman Pfaff

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Re: how can I tell if my 912uls has softstart built in

by Rotax Owner » 12 years ago

Rotax Owner

1 36 0

The quickest way to check is to look at the top of the electronic modules for the color of the serial number tag.

If this serial number tag is yellow, then the Rotax "advanced Start" system is built in.
The newer electronic modules with the built in advance start have a part number (laser etched on the sides, closest to the 1/3 carburetor) of 966 727.

To activate the advance start module, you need to hook up a wire from the bottom 6 pin connector (purple) to the starter solenoid.
Here is detailed info on how to connect it.
PDF Document

Once this wire is properly installed, there is no special start-up procedure needed. It is all "Automagic".

You should notice that the engine will start up smoothly, then with no other pilot input the engine will rev up by several hundred RPM after 3 to 8 seconds.

This is the "ASM" or advance start modules and new flywheel combination doing their thing
The engine will start up in a low power state at 3 degrees ATDC (AFTER Top Dead Center) timing, holding this advanced timing state for 3 to 8 seconds, then flipping over to regular running timing of 26 degrees BTDC (BEFORE Top Dead Center).

Hope this helps.

Thank you said by: Norman Pfaff, Richard Morawski

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how can I tell if my 912uls has softstart built in

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