MF 20 Ind Tranny Oil Change - Broken Spring Found?

[DougH - MF 20 Ind]

Hi all, I am in the process of going through a 1976 Massey Ferguson 20 Industrial that I just bought. My 3 pt. Was acting very jumpy and not raising all the way and the transmission /hydraulic fluid was very milky from apparent moisture so I am changing it. In the process I opened the little triangle cover on the bottom of the pump housing to clean the model MK3 pump strainer (which was badly plugged) and I found a light duty tension/ extension type coil spring about 1/4 dia x 1 long with hooked ends with one hook broke off. Any idea where this spring broke off from? Thanks.

I cant send a photo yet I am told because I am new to the forum and need 5 posts to get permission for photos.

Doug

 

[Jim.ME]

(quoted from post at 22:04:40 10/18/20) Hi all, I am in the process of going through a 1976 Massey Ferguson 20 Industrial that I just bought. My 3 pt. Was acting very jumpy and not raising all the way and the transmission /hydraulic fluid was very milky from apparent moisture so I am changing it. In the process I opened the little triangle cover on the bottom of the pump housing to clean the model MK3 pump strainer (which was badly plugged) and I found a light duty tension/ extension type coil spring about 1/4 dia x 1 long with hooked ends with one hook broke off. Any idea where this spring broke off from? Thanks.

I cant send a photo yet I am told because I am new to the forum and need 5 posts to get permission for photos.

Doug

You show 6 posts now, pictures should work.

 

[DougH - MF 20 Ind]

Here is a picture of the spring laying in the removed cover.

Doug

 

[Frank Dozer]

Whereas I also have a 1976 MF20, you caught my interest as what it
is. I searched the Agco parts diagrams and found nothing that even
remotely looked like that spring. I too just changed that fluid. Mine
was milky. There was some fluid still sitting in the case so I removed
the PTO and it’s cover to inspect inside. I used a leaf blower to blow
inside the cover and about another pint or so came out of the milky
fluid. Note that there is a particular way that filter gets reassembled
with o ring seals, nut, spring and retaining clip.

 

[Jim.ME]

Using the online parts book #651281 there is a spring (item key # 63) on page 241A that might be a possibility.

 

[DougH - MF 20 Ind]

Thanks Frank, I also have a strainer sleeve #73, (see attached) that I dont see with many of the replacement pumps available but it is on the drawing. Also is the o-ring located above the sleeve #68 in a groove on the housing that the filter bolts to? Mine did not come out with the filter yesterday so I will have to check for that one today. I took a picture of that housing with the filter housing through the hole yesterday (attached) and I think I can see the o-ring on the side of the pipe the filter sleeve slides onto.

Doug

 

[DougH - MF 20 Ind]

Jim, That does look like it could be the spring. I wonder what it does or doesnt do if left out. The PTO had been working. I still have the fluid drained so I will try to see where it went. I wasnt planning on tearing things down any further but if I had to remove another cover like the draft response cover I could. Also I dont think I can test things any further without re-filling the oil. I will be looking at it again today.

Doug

 

[DougH - MF 20 Ind]

It looks like that spring is part of the position control feedback to the controls so is probably somewhat important. I did a little digging on line and founds some photos of a project a guy did on a MF 135 (Attached) where the hydraulic lift cover is removed and sitting on the bench upside down. You can see that small spring tucked up under the cover assembly. In position upright this spring will be way at the top of the cover above the two larger springs. It may be viewable by removing the position and draft control cover? Otherwise it may require the removal of the whole lift cover to get at it. I think I will be putting the oil back in with the cleaned filter and see what it does and and then decide on the next step. I will at least see if I can see it with a mirror for now.

Doug

 

[DougH - MF 20 Ind]

I got it back together except the small broken spring found in the sump. Clean oil and a clean pump strainer took care of the hydraulic lift problem. The 3 point now goes up high and smooth. I did need to cycle it maybe 8-10 times before it operated smoothly. For know I am not going to worry about the little broken spring because I am not seeing a problem and it would require the hydraulic lift cover to be removed to even see where it goes from what I can tell.

A few additional notes: my strainer was missing both o-rings #68 & 76 and the special washer #77 that holds the lower o-ring against the bottom of the strainer. I did have the flat #75 rubber gasket that is between the strainer and strainer cover sleeve. I bought the needed o-rings at the hardware store. For the top #68 o-ring I got a 1-5/8 ID x 1-7/16 OD and it worked well. The lower #76 o-ring is 3/8 ID x 9/16 OD, and I made the special #77 washer by taking a 3/8 washer and grinding the OD down slightly so it would fit up under the lower #76 o-ring and still fit up in the tapered lower cone of the strainer without hitting the sides of the taper and be able to compress the o-ring with the spring compressed on it when all is put together.

Thanks all,
Doug