hydraulic oil level on Jet Star

[flatheads & vacuum tu]

My MM manuals cover the 4-Star and Jet Star, and apparently there are some differences in the hydraulic system which are not shown

The blue arrow in the

The blue arrow in the first image points to a filter which does not exist on my tractor.
The red arrow in the second image points to what might by a hydraulic fill point, replacing the filter? The green arrow points to an oil fill plate mentioned in the manual, but it does not state how full is full.
I assume that my hydraulic level is low as the pump growls when I use the aux. hyd.
So where do I add oil and to what level?
 

[SWMolines]

Take the plate off and fill to about 1" below the plate mounting surface.
 

[J.Wondergem]

[T.R.K.]

Brim full at that street elbow with the pipe plug in it. (red arrow) or you can take the rate/cycle lever plate off and put the oil in
there. (green arrow) About 1" to 1-1/4" below that plate. Just be sure to index the levers back in their slots in the control valve assembly
when you put it back on.

What are you running on the AUX ports? I am thinking there is only about 2 gallons or so in the reservoir. If you are using a single-acting
cylinder you may be using it all.
 

[Alan K]

The photo from the manual is an early system, pre 1961 I believe. Bottom picture which is the later system has the filter off to
the left side. Fill as was mentioned.
 

[shinnery]

Beginning somewhere about the M670s MM went to a fill arrangement that replaced the drain plug at the right rear of the oil reservoir. Remove the drain plug and replace with a close nipple pipe and tee, replace the plug in one end of the tee and about a six inch pipe in other end of the tee. My M670 has a dipstick in the pipe but on others I have changed i just eyeball the front of the reservoir and fill it mostly full, as MM wanted about an inch below the top of the reservoir. Then use a pipe cap to keep the dirt out.
Works for me but use at your option.
Bryce