Farmall 706 Multi Control Valve pump-no steering

Since it has warmed up I thought I would get back on the Farmall 706 with no brakes or steering. Last fall while running an auger I found the oil light blinking. Knew it wasn't the engine and sure enough no power steering or brakes. So, I pulled the tractor aside and put another one on the auger. During a wet spell when I couldn't combine I started the tractor again and just happened to back it up a slope and the pump started. Steering and brakes were normal. Before I finished beans the tractor had lost its steering and brakes again. I had sort of blamed it on transmission fluid with too much water in it.

So, here is what I have done to try to remedy the problem:

1) changed filter
2) air temperature well above freezing for several days - nearly 60 degrees the past couple days
3) made sure the transmission oil was at "full"
4) pulled 5/8 inch bolt on the lower back side of the MCV to help prime pump
5) put compressed air into transmission filler neck - enough to get a big gush coming back out when I take the rag away
6) oil looks to be in pretty good condition
7) 2 point hitch and hydraulic valves work

Still no steering or brakes. No oil coming out of the 5/8 inch head bolt taken out to help prime the system

Don't know what else to do!!! Possibly increase the oil by another 5 gallon????? It is full to slightly over filled. I thought compressed air would push it to the MCV pump.

Do both the MCV pump and hitch pump get their oil through the casting cavity where the filter goes??? If so I assume the pumps have to create a vacuum to get the oil into the cavity and through the filter or does the hitch pump pump some in there? Since the hitch pump works the filter cavity must be filling. I would think that would easily make its way to the MCV pump.

Any ideas appreciated. I suppose the next step is a new MCV pump???

A simple and cheap fix might be to overfill the Hytran by 5 gallons. It hurts nothing, and causes no leaks that aren't there already. Putting the oil in covers a failed suction Oring in the pump supply. The fact that it started to work after it was "down hill" is an indicator. Jim

I will second trying extra oil before tearing it down. The suction system is know to have issues. I know of several IH chore tractors that guys run over full for years rather than tearing them down.

Behind the hydraulic filter is a tin cover and behind that cover is a suction pipe that once in a while likes to move out of place. Check that but be careful when pulling the cover. If that pipe is out of place all the oil will drain out in a darn quick hurry.