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Posted: Tue Jun 12, 2018 5:32 am
by Duane
On the oleo oil, If you have the original springs, p/n 4015B, then just some good quality tractor oil. However if you have the newer 4161B springs, then you must use API GL-4 or GL-5 85W-140 gear oil.

Posted: Tue Jun 12, 2018 8:00 am
by Andy Young
Duane wrote:On the oleo oil, If you have the original springs, p/n 4015B, then just some good quality tractor oil. However if you have the newer 4161B springs, then you must use API GL-4 or GL-5 85W-140 gear oil.
This is first that I’ve heard this. What is the rational behind needing the different fluid with the new springs?

Posted: Tue Jun 12, 2018 10:23 am
by Duane
It came about by the way we had to do the drop test with the new springs. The thicker oil helps by slowing down the compression and in dampening. Our friendly FAA had changed the way we had to test them over the way it was done originally.

Posted: Tue Jun 12, 2018 11:35 am
by Andy Young
Ah. In other words, if one was to inadvertently use the old-spec oil in an airplane that had the new springs, it would function and react more or less like they always had prior to the new testing regime.

Posted: Tue Jun 12, 2018 12:32 pm
by Duane
LA LA LA I didn't hear anything. 8)

New rules

Posted: Tue Jun 12, 2018 8:48 pm
by VA Maule
Now play nice Andy you know they only make new rules to protect us from ourselves :roll:

Posted: Wed Jun 13, 2018 1:54 pm
by crbnunit
The MAN is just trying to keep us down! :lol:

Posted: Wed Jun 13, 2018 4:13 pm
by UP-M5
i have the new 4161B springs with synthetic 85W-140 gear oil and i don't notice any difference in compression or rebound. i do notice that the new springs sit up taller than the 10 year old ones they replaced. and the extended landing gear makes seeing over the cowling an entirely new challenge :)

Posted: Wed Jun 20, 2018 10:01 am
by freedom
finally the landing gear is back on.. 21yrs since the last time!!! a milestone has been reached.

Image

on a side note, is it correct that where the main gear and the oleo strut join, there is no bushing_ the hole seems quite large. only thing I can think of, is that the bolt has to be thighten quite a lot, for the 2 bushing inside the oleo to fit in the large hole.

Imageimgupload

Posted: Wed Jun 20, 2018 10:16 am
by maules.com
Something wrong with that picture. The hole is too big.
There should be a swivel bushing but I see no way it can be captured.
The hole must have been opened out for some unknown reason.
At this point I would advise getting the extended gear, though that does mean extended oleo struts too though you can use your existing spring packs as long as you have the latest type.

Posted: Wed Jun 20, 2018 10:27 am
by freedom
:x :x .. just found it.. it's the same part number for the oleo ball bearing.

does it normally need to be pressed in with force?
what is the correct hole diameter?

Posted: Wed Jun 20, 2018 11:15 am
by maules.com
I am not at hangar but according to memory it fits up against a shoulder and is either peined in four places or held with circlip.
I don't know outside diameter of bearing or inside of hole.
The upper bearing in top of oleo is positioned with thick spacers on each side of the bearing between the landing gear lugs. The nut is torqued on the bolt at 225 inch lbs. Be sure correct amount of washers are used to prevent torqueing against the shank, easy mistake as the lugs are slightly splayed and are pulled together prior to achieving torque value. Cannot be acurately torqued with bolt head.

Posted: Wed Jun 20, 2018 11:26 am
by Duane
That hole size should be .810 dia.

Posted: Wed Jun 20, 2018 4:21 pm
by maules.com
I looked, there is no shoulder, the bearing is held in by pruning four points on both sides at the lower attach point. However the upper attach does have a shoulder and the bearing is held in with a spring circling.

Posted: Thu Jun 21, 2018 1:21 pm
by freedom
upper attach is properly installed.
Have measured the bore size today and is within specs, so tomorrow will press in the bearing.
Today have also cut the central tube in the from doors and welded in a curved bar to increase cabin size. Pics to follow.