Hey folks, This '74 Case 850 is almost impossible to steer using the brake pedals. It does somewhat ok on an upgrade, it becomes harder to brake on level ground, but when traveling in reverse on a downgrade it takes all my might to disengage the tracks (thus no turning or braking) ability. The following photo is its Transmission Control Valve (TCV) We have all new seals that goes in the TCV, fairly new master cylinders & slave cylinders. We have bled out all the air in the brake lines. The slave cylinders & brake levers does operate with the brake pedal. I removed the back plate (#2) on the TCV & the brake spools (#10) do function with the brake pedals. All the mechanical(s) check-out. My 5,000 page service manual states "Check to see if the spools fit their respective bores with a slight hand pressure & w/o excessive side clearance". That is not a very scientific description! They should have included wear limits in this manual - especially when it comes to brakes. Does any1 know how much is too much? The min spool diameter? The max bore diameter? Can just enough fluid pass through worn spools to make the drive train clutches only partially disengage? such as clutch slippage. What else can cause the tracks to keep driving when the brakes are depressed?
May be mistaken but the last 850 I got on had hand levers for the clutches and brakes were only used to make sharper turn after the lever was already pulled?
This uses high-low levers connected to the TCV and those various spool positions (#4) sends hydraulic fluid through various lines, which pressurizes clutches in its transmission case. when the brakes are pushed, the 2 lower spools (#10) cut-off all fluid to the trans. thereby neutralizing the drive train as the brakes are applied. it sounds like the same operation & i use the high-low levers for wide turns. the brakes for sharp 90's, 180's, etc. i hear the brakes & drive train are becoming a bit more cooperative, so maybe the new seals just needed a little break-in period. still, the service manual should have been more specific. i just don't want to spend $200 on 2 spools & still not be fixed.
The 850's we had would disengage the track when the brake pedal was pushed ,and the farther down you pushed the pedal the brake would start to engage. It took a decent amount of effort to lock the track. Your legs would be tired at the end of the day for sure. If it has the trans pressure gauge , it should fall back when the pedal is pushed. Your actual brakes could be worn causing it to take more effort to turn. The E models and up had hydraulic assist which worked better.
that is exactly what we are having to contend with Dickjr the brake-spools (part #10 (above)) disengages the drive train on this 1974 Case 850 .....and it does take a tremendous amount of leg power to stop the track. i just thought something was malfunctioning to make it that hard to brake-steer. the brake disks might be worn (or wearing) out too, because the slave cylinder adjustment bolts (part # 32 (below)) are almost fully screwed in. i dread messing with that but if it will make it easier to use then it'll be well worth it :usa Thanks for the advice Dickjr
Looks like the brakes are dry type? If so they more than likely need relining and cleaning real well. The actuators need to be cleaned and checked for wear in the moving parts that could cause binding.
It's true that they are dry brakes & it never occurred to me that they might be binding up - making it harder to use. For some odd reason 1 of the former owners welded the brake actuating shaft (30) to the brake lever (34) ..so we may not be able to disassemble it, or possibly grind it apart. I just want to use this machine some day instead of perpetually working on it, but we're getting there.
In your first pick idem 21 is what pushes the brake cutout spool that dumps the pressure to the track depending on which pedal is pushed. The brake system did not last long on those machines, they glazed over or crud would get in the vane's in the disc, oil leaks inside the housings and you could not put enough force on the pedal to stop the machine. I kind of think you think it's still pulling but the truth may be they are glazed or oil soaked. We would take a rat tail file and cut the groves on the disc's to let the crud out. Those are the same type disc used in many of the older farm tractors and you could ruff them up/sand blast/bead blast them and they would run for a little longer but would fail again down the road. This is why they went to wet brakes to solve that problem on later C/D machines.
Every1 was right. The spools are disengaging with brakes. It is the brakes that are dysfunctional. I found this out the dangerous way as I was on a slope, the machine got a bit out of control, so I hit 1 of the 2 brake pedals. That track sped up (instead of stopping) while the other track maintained speed & launched me into the ditch & into sapling trees!!! i nearly needed a change of underwear. Out of habit (and panic) I managed to make that error a 2nd time & lived to tell about it. Fortunately, that is the worst part of the driveway & it is nearly done. I hope I survive it!!! Anyways, I just wanted to express my many thanks for coaching me through this restoration process. Y'all are grrrrr8 people :usa
I'm just starting in on my 1974 850 Bulldozer. The undercarriage is a wreck and "shocker", the brakes don't work!!
I have reading posts for awhile now to help me restore an old 750 case track loader.I have completely rebuilt everything except the engine The brakes and hardware Pedals master cylinders and brake housings have been removed a long time ago .After reading anything i could find on the internet most people who operate these machines say the brakes were the first thing to go and are not worth fixing.I have been restoring a few years now and hope to get it moving this winter . My question is is it possible to put line locks or something on the control tower to give me some kind of brake or parking brake as the land have has some hills i need to put roads on.
If it has old brake pads , you could remove the old liner, and make up new ones and rivet the liner back on . sam .
Thanks for replying Sam the brake housings and everything was removed i was just wondering if i could do something on the control tower
frankieavalanche, the brake discs stop the pinion shaft from turning, that is the reason the cutout has to drop the pressure so your not driving threw them while driving and trying to stop and or turn. The discs hold with the parking brake applied to the pinion shaft, which causes the ring gear/ bull gear /axle shaft /sprocket / track not to turn. Their is nothing you can do with the control valve to change this set up.
Thank you sheepfoot. I certainly will have to get used to the machine.The brake system was removed a long time ago according to previous owners.I did see a link awhile ago where a guy added levers to the control valves . I think what he was doing was making it easier to turn buy disengaging one side at a time for quicker turns, or both sides to make it less harsh on the transmission shifting from forward to reverse. I agree there is nothing else i could do to change the setup to have brakes.
First item returned to function on my Allis was the brakes, I live in hill country and appreciate being able to stop or park my machine and be comfortable it will do so when needed.
well i finally got to running the 750 track loader . Getting along fine with no brakes . I am trying to get the generator to work .Its 24 volt positive ground Delco Remy no. 1105228. I am keeping it that way . I purchased new parts for the generator. (Bearings brushes&field coils). The field coils i took out have three wires, the new field coils only have 2 wires.I added a wire in between the two field coils.This is were the third wire was on the original field coils and wired them the same way but i still can not get the generator to work. I have polarized it every time i put it back on the machine. Any help would be appreciated.
Ok I have a 750k dozer 04 model I was having problems with it not moving forward or back I got the right track to move but the right side try’s to move but just moves about inch and stops do y’all think it might be the break and the break pedal is real soft
Have you replaced the regulator for the generator, cannot remember a 750 with a generator these most often had Pos Grd Alternators.
Hi DMiller My Generater rebuild was good .After running the machine for a while the starter went out The guy that rebuilt the Starter suggested changing to negative ground and showing me how easy it was i gave it a try and lo and behold the generater started charging. I have run the machine quite a bit now .It works awesome. The only trouble i had was i got very comfortable operating and started using high gear. Well i was on my hilliy drive way in high gear backing up grading with the bucket down and she stalled.I went for a ride on the side of the driveway into the ditch. I did not get hurt but it was a good lesson not to get too cocky
Hi Alex i hope you solve your problem i won,t be much help all i have is two real old machines 1967 case 750 1957 Cat 955 both totally different brakes.The case has no brakes when i got her the pedals were cut of and most of the inside parts were missing after a lot of research and answers from other members the conclusion was not to fix them because they were too expensive and did not work that well anyway.Thereis some members who still felt brakes were needed for loading but if you have just a blade machine you may be alright but going to job sites loading and unloading my be difficult with no brakes
I live in hill country, would NOT have a machine no brakes as dangerous. Worked in quarries where trucks had no brakes for any length of time, operators accepted that as a norm and injuries did occur, not really smart.
Totally agree with you I am retired and have a piece of land in the country where i haul about 15 cords of wood home to burn in my garage this also heats my house pipes under ground. The only reason i have the 750 is to maintain the driveway and putting some wood roads in. I do not use it commercially I knew the brakes were gone when i got it.This machine has not had brakes since the early 70s.Every time i find a machine like this (old 850s too) the brakes are a thing of the past because they are a poor design if you try to use them to stop your machine will speed up .I did a lot os research on these machines this was the norm back in the day(not saying its right but if you ever operated one you would know what we are talking about)When you push the brake pedals it releases the transmission and if they are wet dirty wore or a leak or etc.etc.they will not stop the machine.They were to say the least high maintenance hard to work on and lots of downtime if you demanded they work. Just my two cents but old Case dozer or loader operators will all agree with me.
May be true but following another down a dark path is not always smart, fixing the problems is. Seals, bad bearings allowing leaks, repairing brakes to maintain some level of function is better than none. Riding the sled backward down a hill unable to stop is asking to die.
This is just one of many post about these machines found when doing research but i agree it does not solve the problem of trying to stop a stalled machine on hilly ground. i am going to try to set up a braking system that can be used if the machine stalls something like a disc brake setup on a monster truck only putting this on the brake shafts sticking out of the transmission = see picture Dozerbill63 Well-Known Member Joined: Nov 12, 2012 Messages: 65 Location: Repton , Al. Brakes ? You don' t even need brake pedals on a 450 or 850 , I removed the pedals completely off both of my 450s , you steer case crawlers with the levers , true enough the pedals are for quick turns , away from trees , basement walls and such . If you do not know much about the brakes ,they can get you killed . Loading case crawlers on trailers is the most dangerous thing you can do using brake pedals . If you push the pedals half way , you will free travel , pedals must be pushed all the way. You are suppose to steer with the levers PEROID ! Last edited: Dec 30, 2013
Brakes are brakes, no brakes is just foolish. Know all too many with these particular crawlers, they still keep brakes functional and Yes am aware steering done by the levers on these. Allis and Cat were opposite, levers were clutches Only and often had to nudge a brake for better response. Deere is a breed unto itself with this in mind too.
I totally agree with you Frankieavalanche, if they were not suppose to have brakes they wouldn't have come out with them on the machine. But sometimes the OEM stuff just doesn't work or last as long as they should. I know this is several years since you inquired on this brake stuff, but I just retired and been a service tech for a const company for past 30 years and a service tech for a JD dealer 16 years before that. I was just asked by a farmer that has a Case 850 about brakes not working on one side and that is how I found all this "GREAT" info. I'm trying to decide if I want to run from this job or prove to myself that all mechanical problems can be solved or improved. From all the comments from some owners that have took they brakes off, you should be able to collect enough parts to reassemble your machine. From what I see these brake systems are like several systems used on older Oliver, Case,International, Deere,etc. You have 2 thick round metal plates with 3-5 balls setting in recesses in between the plates. The recesses have ramps on them so the plates can rotate in opposite directions , therefore making the 2 plate assembly thicker when rotated in opposite directions and putting outward pressure on each brake disk with facing , that is spline to shafts extending from transmission. With the 2 plate assembly and both brake disk encapsulated between the wear plate against the transmission case and the outer cover housing, there fore applying a braking force to transmission shaft that is connected to transmission output shaft for each final drive unit. Springs connected to each thick plate pull plates back to collapsed position therefore releasing pressure against brake disk. There is links connected to each thick plate that are connected to a common pull rod, so that when the rod is pulled it pulls the links together , therefore rotating the thick plates in opposite directions. Yes the weakness of this system is the brake disk getting glazed over from heat, wear dust, oil from seal, outside contaminates thru pull rod hole. But if you can put enough pressure on that pull rod, you can stop anything as long as the clearance between all the parts involved do not exceed the travel of the 2 thick plates as they spread apart. The hardest part of connecting an extending cylinder ( for hydraulic enhancement) to this system is engineering a lever system that can with stand the pressures that can be applied. Hope this info helps somebody as much as the info I discovered on here has helped me.