R44 RII Hydraulic Reservoir Filler Size
 

On pre-flight noticed the hydraulic fluid in our R44 RII is lower than it was prior to going in for it's 100hr. No leaks found but as fluid is just showing in the sight glass, which is ok for flight, and not the middle area as normal I want to top it up and monitor for usage.


Anyone know what the filler nut size is - all the robbo maint manuals & POH's specify the correct torque setting 100inch pounds (11NM) but not the physical size? Just want to make sure I have the correct socket with me for the wrench. If not I'll have to get the verniers out!


cheers for any help

I would be quite concerned about that. I was asked to help top up a 44 reservoir recently.
A small quantity of oil was visible (just) in the sight glass. Dipping the reservoir revealed that it was virtually empty. This issue is widely known, Eurocopter put paint across the lower part of the reservoir sight glass on the 365's to prevent people being fooled by a small quantity of oil being trapped in the sight glass.

I agree - which is why I want to top it up and monitor. I was a bit surprised when it was flown back how it was!

It may be lower because it is cold and not used for a bit while in maintenance. Check for leaks also.

No leaks evident after extensive investigation. It's not cold. I think it was filled with hydraulics off and not cycled on and re-checked during the service. But that is all academic as they flew it away.


Just need that imperial nut size - anyone?

Just take a socket set, from memory, it is a 5/8" but it could be a size either side, 9/16" or 11/16", 3/4" at the most.

To be fair the rules may be more relaxed if there is no public transport work on that machine (I wouldn't know, as all my machines have been so used), but I don't think I am be allowed to top-up the hydraulic fluid reservoir. It would require a qualified engineer to do that, and I always go get one.


I am allowed to add petrol / Jet A1 (as appropriate) and engine oil: that's the limit.

https://www.easa.europa.eu/system/fi...%20Part-M).pdf

Page 135 (last paragraph) is relevent if you are a pilot owner and the aircraft is not being used for commercial purposes.

Page 140 ATA Section 12 covers Hydraulic top up.

Yes was aware able to do - a lot more on this list than I would attempt though!

Do t you just love regulation document speak FAR/AIM ironically is in plainer English 😱

Thanks for the nut size and other replies. Robbinson replied to a tech email on Friday in the end.