Mandatory ALERT Service Bulletin: Inspection and Replacement of Oil Spray Nozzle for ROTAX® Engine Types 912 i, 915 i, and 916 i (Series) SB-912 i-016 / SB-915 i-016 SB-916 i-006

When this scenario of failure happens does both A and B fail at the same time or does just one fail and you get a Lane light?

For anyone who wants to make accurate stator winding resistance measurements but lacks a precision meter capable of 4-wire measurements, here's an article and tool design from Bob Nuckolls that makes it pretty easy.

http://www.aeroelectric.com/articles/LowOhmsAdapter_3.pdf

Here's a link to a parts list on Digi-Key with all of the necessary components.  You'll just need wire and some sort of enclosure; Digi-Key has plenty of those in stock as well.

https://www.digikey.com/en/mylists/list/4U5M8OOEVE

Note that the Digi-Key parts list contains two 25-ohm resistors instead of one 12 or 12.4-ohm.  If you put two 25-ohm resistors in parallel you'll have a 12.5-ohm resistor, which will make this device as accurate as possible.

Hi Eric

The adapter you posted seems well suited for a low resistance test through the stator windings, but since it operates at 1.25 volts I don’t think it would be effective at looking for leakage to ground at higher (operating) voltages.  I believe the open circuit voltage of these stators is >35 volts. What do you think about using an insulation tester on the lowest setting (50 volts) and testing each lead to ground?  In my industry insulation tests on larger generator stators are routinely done at 1.5x the system voltage, so 50 volts should be about perfect for the Rotax stator.  I’m not recommending this, just thinking out loud.  

Yep, it's only intended for low-ohms resistance testing.  I think your idea to use a "Megger" type insulation resistance tester at 50V is sound.  If I had one, I'd do the same thing.

EVERYONE!

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