Diagnosing 3 pt hydraulic problem on MF 30b

[foster4]

Bought this used when it was colder out. After it warmed up, the 3 pt (w/ box scraper/scarifier on it) would raise a little once or twice, never to full height, then wouldn't respond at all. Obviously something related to viscosity, and I'm assuming leakage around a valve or the piston rings.
Service Manual says to remove the side cover and ck for leakage in cylinder, stand pipe, control valve, or valve chambers. I pulled the cover, but I'm not sure what I'm looking for. I can see the cylinder, and it didn't appear to be leaking when I tried to raise the 3 pt. Not sure how to ck for leakage in the valve or valve chambers through the porthole. I did pull and replace the o rings on the standpipe, but they didn't look bad, and that didn't make a difference. Also, why is it always the right cover that is to be pulled; almost looks like you'd have better access through the left side.
Thanks.

 

[foster4]

Maybe I didn't provide enough information. This is a MF 30b industrial, probably from the early 80's. It has a loader on the front, a box scraper/scarifier on the back, 3 cyl. perkins diesel, and no rear pto. I clearly didn't check it out well enough when I bought.. should have ran the point up and down til it was hot and cked for function and drift... but I didn't. The guy told me everything worked but the 3 hydraulic cylinders that were obviously leaking. I did a cursory ck, and believed him.
After rebuilding the 3 hydraulic cylinders, the starter solenoid and the front wheel spindles, I thought I was set to go, then discovered the 3 pt would only barely lift once or twice.. never to full height, then wouldn't respond at all.
Now I have a 3 pt that doesn't work, and I'm trying to do whatever I can to solve it short of pulling the lift cover.. and if I do have to pull the lift cover, I'd like to have as much information on where the problem is that I can get before starting.
So.. if anyone knows how to check for leaks at the cylinder, the stand pipe, the control valve, and valve chambers.. through the right side cover porthole, or has any other helpful information to offer, I'd appreciate it. I've got the service manual, but it doesn't tell how to do a lot of this.. just to do it.
I need to get this running so that I can get the driveway back to suitable for 2 wheel drive vehicles before the snow hits.
Thanks.

 

[irvingj]

foster4-- What you're asking about is way beyond my experience/ability, but I did a quick search. Try this on Google: "big deans massey ferguson".

There seems to be a fair amount of pretty detailed info on older MF tractors in various links, many of which refer back to TBN; there are even some specifics that refer to (what sounds like) just what you're experiencing, complete with pics. Apparently not an unusual problem, from what I gathered. Perhaps you can find what you're looking for.

ijk

 

[Winmac]

To check for leaks you would operate the hitch and look internally through the opening for leaks, you may see fluid spraying form the stand pipe or if leaking below the oil level you would see fluid moving where it should not be.
If you have not seen a working system operate you may not recognize issues, it's kind of vague what is normal or not.
You have to remember the manual was written back in the day so Wear a face shield at a minimum.

 

[foster4]

foster4-- What you're asking about is way beyond my experience/ability, but I did a quick search. Try this on Google: "big deans massey ferguson". There seems to be a fair amount of pretty detailed info on older MF tractors in various links, many of which refer back to TBN; there are even some specifics that refer to (what sounds like) just what you're experiencing, complete with pics. Apparently not an unusual problem, from what I gathered. Perhaps you can find what you're looking for.

ijk

I searched for the site, but all I find is a few references to it from this forum. It doesn't appear to be active any longer. But thanks for your help, I appreciate you taking your time to help.

 

[foster4]

To check for leaks you would operate the hitch and look internally through the opening for leaks, you may see fluid spraying form the stand pipe or if leaking below the oil level you would see fluid moving where it should not be.
If you have not seen a working system operate you may not recognize issues, it's kind of vague what is normal or not.
You have to remember the manual was written back in the day so Wear a face shield at a minimum.

It does throw a little oil out; but you pretty much have to look through a mirror anyway. By the time you get a mirror and a flashlight on it, it's tough to see, but I think I would have seen any major leak from the cylinder, because the oil would have to have been dripping or splashing down into the fluid level, and that I can see directly. The part of the manual I don't understand is how I'd ck for leaks at the pump valves, although it does say that if there's a pump leakage, it will usually come w/ audible noise. I'm going to get a 5K gauge to test pressure at the transfer cap port.. but that doesn't eliminate much, because it could still be the control linkage, a leak or malfunction at the pump; pretty much only eliminates the cylinder.
I did notice that there is very little movement of the control lever when I move draft/position controls. I tried it again w/ engine off, and the little movement I got seemed to correlate w/ when I would get a bit of lift w/ engine running. Do you know how much movement I should be getting? I can't seem to manually move the valve control lever that the control lever acts on, or I could do that to see if I get more lift action w/ engine running.

 

[foster4]

irving j.. I think you may have provided the answer. I went back and looked at "big dean's" site, and I found this:
Three point & PTO On Instant Reverse
The Instant Reverse Transmission or sometimes called a hydraulic shuttle that are found in a lot of the Industrial tractors. The PTO & the hydraulic pump will only turn when one of the pedals is pushed down. In order to raise the three point you either have to be moving or have the shifter in neutral with one of the pedals pushed down. Most of these did not come with PTO on them.

As I mentioned at the start, this is a MF30b Industrial. I have the service manual, the parts book, and the operator's manual.. and none of them mention this. I'll give it a try.