Oils aint oils...

[Planechaser]

So I had Aeroshell sports plus 4 10w-40 in the 912 uls for the first 25 hours, and the oil pressure bounced between 45 psi and 69 psi at 4800 rpm. I was told this was because of my choice of MGL digital oil gauge being too acurate.... They actually had to put an adaptor in the system at Morrabin because it was fluctuating enough to set of the alarm!

 

I just put in VSX 4 15w-50 ( on the general advice of Bert Floods) and the pressure bounces between 43 psi and 47 psi!!!

 

So is anyone else having any oil pump or pressure issues with the 10w-40?

 

And thanks to the team at Floods for the tip.

 

 

[Guest Maj Millard]

I think they are correct about your digital guage being too accurate. Too many people get excited about 912 oil pressure flucations. The range is small but as long as you are in it per Rotax recommendations you'll be fine.

 

I personally chose the Valvolene range after initially using Castrol GPS for many years, until it became non-recommended by Rotax. I don't like Shell products although the VSX seems to be fine. I currently run Valvolene Durablend 15w50 and it performs very nicely. I don't like running a 10 wt oil up here in the North due to expected high temps in Summer months. Hope this helps.....................................................Maj...

 

 

[denmit]

I understand that Rotax OP fluctuations are an irritant for many using digital instruments. US based Rotax operators are installing a restrictor between the oil pressure take off and the sender unit which smooths out the fluctuations.

 

 

[denmit]

Also, see this post on the RV-12 Forums at VAF if you are also seeing fluctuations on other engine readings as well.

 

http://www.vansairforce.com/community/showthread.php?t=56156

 

 

[BPN]

There is a Rotax service bulletin on this very issue with deals with both instrument error and other possible causes .

 

BPN