Since, and only since, installing the third partly CKT exhaust having to remove the header pipe on the number-2 cylinder to spin off the filter, and it seems to be related to the issue of the clearance of the CKT pipe from the filter being smaller than the clearance of the former stock Rotax exhaust header. Working on a possible resolution with Chris Piper at CKT, but in the meantime figured I`d throw this out to you other CKT 912 folks.
So I'm curious if you or any owners with 912's you know of have had to remove their exhaust pipe for filter changes, or if that issue is somehow unique to our Skyranger ELSA CKT installation?
FWIW: Rotax does say it has increased the length of its 912 filter by about 4 millimeters.
(825 012 Rotax Oil filter, Replaces 825 706, 3.4mm longer)
Don`t know when that increase took place, or if 3.4mm is enough to cause our issue.
Not that happy with having to remove and replace the number-2 header at each oil filter change. Not significant work to do so, but, even though one of the Skyranger experts assures me the sky (and Skyranger) probably won`t fall if I properly do the remove-and-replace, I just don`t like taking things apart unnecessarily because, as my mother used to say "are you SURE you`re going to put that back together properly?" ;-)
Also FWIW: I note at least one accident in which a contributor cause in fact was the 912 owner having a similar problem with an oil filter not quite clearing the exhaust header pipe and using the same workaround (remove and replace the exhaust pipe when changing filter.):
http://www.tsb.gc.ca/eng/rapports-reports/aviation/1997/a97o0055/a97o0055.asp
www.tsb.gc.ca/.../a97o0055.asp
"Transportation Safety Board of Canada
10 January 1997,
----- with oil filter Rotax P/N 825-701. ... the original filter and, when installed on the engine, reduces the end clearance with the No.2 exhaust pipe. ...
The increased length placed the end of the filter closer to the exhaust pipe;
... When the quantity of oil in the engine became insufficient to supply the oil ... "
Alex