Hi, been lurking in the forums for awhile, first post... We have a 1973 Massey Ferguson MF50 tractor loader backhoe in really good working order, wonderful machine, does real work. For some reason this machine was built with a single brake pedal, looks like Massey upgraded to a split brake pedal system in later models, not ideal but oh well. One of the brake slave cylinders on ours recently gave out. I have gone through the parts catalog for the MF50B loader backhoe - closest I could find - with a fine toothcomb and it appears to include every single part of the machine except for the hydraulic components of the braking system. No matter, I found a reference for a part number for the slaves for the MF50 loader at this related thread: HeavyEquipmentForums I have two of these slaves in hand now and was planning on replacing both at the same time, but now I'm realizing these slaves were designed for the later Massey braking systems that use a separate brake master cylinder for each brake slave, whereas mine uses one brake master cylinder split across two brake slaves. So no reason to think my old master is going to work as designed with these two new replacement slaves, perhaps it will work but with only half braking force at each wheel, or who knows. Worth mentioning, the old master cylinder still works but I would prefer to replace it now while I'm already working on the brakes. Wondering if anyone has encountered this before and might be able to recommend a good master plus dual-slave parts combination that would work well for our application? For reference, the master cylinder in our MF50 is of the type pictured in post #35 in the related link above. Also I'm assuming I'm going to have to run new brake lines and flare fittings, not a concern. Thanks in advance for any pointers you might can offer! Joshua Finkler (Buffalo Creek, CO)
I have the manual for a MF50, I can send the brake chapter if you want. PM you email and I'll send it. It's a typical British manual, expensive and not of much use but does have some poor quality pictures to go with the poorly written text. Joe H
As long as your linkages remain the same, that is you're not changing the leverage on the cylinders. Then the diameter of the relative cylinders is all that matters. If the new slave cylinders are close to the old slave cylinder diameter, it will work fine with the old master cylinder. A new master cylinder of the same diameter will work fine. The big difference would be a much smaller or larger diameter cylinder. Or putting two slave cylinders on a master designed for one, you'd have as much force but the brakes would have less play before you ran out of stroke on the master cylinder and ran out of more pressure.
yes, this is what i was concerned about, the possibility that since the aftermarket slaves were designed to each have their own master that they might result in less force or as delmer says less stroke play. i think i'm gonna go with delmer's suggestion to just get an apples-to-apples replacement for my master and plumb it with the new aftermarket slaves and see how it goes. worst case scenario i'll have some more information about what does and doesn't work, and if a different master bore size looks to be necessary then i'll deal with that then.
Just compare the diameters. Post the numbers here if you're concerned. You still have the separate stand up mechanical foot brakes, right?
Delmer, I'm not exactly sure what your question about stand up mechanical foot brakes is asking here, my apologies, still learning proper terminology. The brake system on our loader is complete and intact and was working just fine until recently when one of my two slave cylinders started a slow leak. We only have a single non-split brake pedal which operates a single master cylinder which then splits to two slaves, so no independent left/right brake steering/braking, just braking for both wheels simultaneously. There is a separate parking brake actuator with locking latch. Hope this clarifies, thanks for your continued help, much appreciated!
OK, I've seen **'s with both the single front left foot pedal for hydraulic brakes, and two separate pedals coming forward from the axle that you basically have to stand up and step on to brake the sides independently. You'll see soon enough if you have the same braking force. And the big yellow brake out front if you need it.
copy that, ours has a clutch for front left foot and a single right foot brake pedal that splits to both brakes. from the looks of the literature by the time the 50A loader came out they were already building it with a latching split brake. pics attached of the controls on ours as well as an overall, you can see that the backhoes on these are maybe at the limit size-wise for these tractors. the big yellow brake out front is currently all that is holding it where it's parked while i sort out the brakes!
Ok, you have a 50. The 50B manual you looked at is entirely different (and euopean) The 50A and 50C use mechanical brakes. parts.agcocorp.com Go to "Search by Parts Book" then put in 651291 under model. Due to the stupid model search it is hard to find the book. 651291 is the book number. Page 129 has the braking system. Page 137 has the cylinders. What I have seen it looks like they used both Wagner and Bendix Cylinders. If you can get the part number off of it perhaps an auto store can help?
Awesome find for making it easier for jfinkler, Sportsman ! Below is a link to it https://parts.agcocorp.com/en_US/apbsearch?q=masseyferguson/651291/l&c=00-00&name=50 TRACTOR
Direct links to the agco parts books don't work. Not sure why, but its annoying, hence my really long winded explanation on how to get to it.
That link is working for me today. I even cleaned my my browser cache last night. I do that every night.