XPS oil for 912iS

Peter,

I would guess that an oils ability to run cooler is based on the its “thermal conductivity”. This is the property that allows an oil to absorb heat from the engine components, and then conduct that heat to the oil radiator.  I found a spec sheet for the XPS aviation oil on flyrotax.com, but it did not list the thermal conductivity value.  

Hi All

The oil is a full synthetic.  The base stock is special and had to be blended to tolerate high peak temperature without breaking down so it will maintain the oil qualities needed.   

So the main problem with oils in aviation has always been how to deal with lead in avgas.  Synthetics in general do not like to suspend lead which leads to high lead drop out when it is saturated.  Regular petroleum oils will absorb a lot of lead as we know from experience,.  The Shell is a semi-synthetic and blended oils like it were often used in Rotax.  It took a long time and a lot of testing to get the XPS to suspend the lead and maintain its properties,  XPS will have some tech talk on the oils soon, like they did at Oshkosh last summer.  

I will try to get some data ifM you like.  The  oil has a lot of customo things that were developed to work in the Rotax, even the oil dye is for ease of viewing the level on the flat dipstick of the dry sump can.  it is a high vis yellow-green so that even with clean oil you can see its level correctly.  Nice touch i think.

Cheer

XPS

XPS

Anyone found an equivalent oil supplied by a major (reputable) brand??

OR

For non AvGas users, an equivalent oil, that may not have the lead scavenging of XPS,  but confers all of the other benefits of a synthetic for us ULP only,  Rotax owners

There won't be a full synthetic that will suspended the lead from 100LL with other full synthetics. This is one reason we have used semi-synthetic all these years. The XPS was completely re-formulated for this amongst other things. I really don't know that much about all the details, but it will be interesting to see how it all works out in the future under real time and long term use.

Hi Roger,

I may be interested in a full synthetic engine oil for my 912ULS. 

I fly in Australia, where ground temps can be up to 45C + but more challenging airborne temps can be as high as 26C at 5500 ft. When flying (not often) in these conditions, it can be struggling to keep my engine oil temperature below 120C - a full synthetic oil might be very useful.

I don't need to have the lead scavenging ability of XPS, as in 15 years of flying behind a Rotax 9, I have only had to resort to AvGas two times and then only as a top up (shandy with ULP) to get me to the next airfield with accessible ULP.

Is there a full synthetic (less lead) that meets Rotax standard?