John Deere H oil pressure issues

On startup the oil pressure comes up to "M" then it slowly drops off to "L" and then a little below is where it stays. I can bring the RPM down to idle and then speed the engine back up. It will then go back up to the "M" and slowly drop off again.

I changed the oil and filter on the H I just acquired before I got it running. I thought there should be a spring in the filter assembly but i couldn't remember if there was Spring in the Filter Assembly on my A. I have since confirmed per the Parts Book there should be one. I'm going this weekend to check on a Parts H in a local parts yard to see if it has the items i'm missing. I wouldn't think that the lack of spring would cause the issues I stated above. Sorta figured that It just prevents oil from going around the filter. Would you guys agree with this?

I'm waiting on my manual, per tractordata, the oil capacity is 4.5 qts and thats what i put in it. I was thinking maybe it was low but per the level check it has plenty.

Any idea what the problem is if its not related to the lack of the spring?

I'm not sure that adjusting the oil pressure will fix it since it seems to actually provide ample pressure to begin with.

I would turn the adjusting screw until it has high pressure at startup and it will probably settle back to M when warm. Mine does that. When warm, if I idle it down it stays just above the L.
I use 15-40 Rotella in mine year round.
Richard in NW SC

Probably not affecting pressure so much but running w/o oil filter
spring allows dirty oil to go around filter.

(reply to post at 12:34:40 09/29/15)

Click to expand...

Oil pressure adjustment only affects max oil pressure . Has nothing to do with oil pressure being too low.
This would be the time to find out the actual oil psi recommended and test with a known accurate gauge. The dash gauge could be out of spec.
The engine could also be just worn and looses oil pressure sun the viscosity drops.
Try straight 40 weight instead of a multi weight .

I got the spring and changed the oil and filter to install the spring.
My problems went to worse. No Oil pressure. I removed the plug to adjust the regulator and was able to get it to show on the gauge, but no better then M. It would drop off eventually. I have a known good gauge but I didn't have the proper fittings to install it. I removed the line going to the gauge while the engine was running to check oil flow and i get oil but alot of Air. I wouldn't think that I should see that. Any idea what maybe the cause of all the Air?