Hello OM and ksliger
If ksliger has posted the correct final drive pic for the 977H then it is different to the D6 as that is a double reduction final whereas the D6 is only single reduction. That should put less load on the bevel gears.

Old wrote:

What your showing is the final drives. I'm referring to what drives the finals through the clutches. For comparison the bevel  gear could be described as the ring and pinion in a vehicle only in a tractor the ring gear/bevel gear is directly mounted to the hub  ( no differential gearing)
I'd post a picture but I'm in the middle of transferring my files to a new computer and every things out of whack right now.
While your in there the steering clutch  release bearings should also be checked.

 

Thank you Old Magnet. When you get a chance could you please share a picture or illustration of the bevel gear hub that you mentioned being the weak link. I can't seem to find this in the service manual or parts manual. Are there specific components of this bevel gear hub that should be inspected while in the belly of the beast doing brakes?

PhilC wrote:

Hello OM and ksliger
If ksliger has posted the correct final drive pic for the 977H then it is different to the D6 as that is a double reduction final whereas the D6 is only single reduction. That should put less load on the bevel gears.

Indeed the picture I posted is from the 977H service manual with the correct serial number range. FYI

If you have the parts manual for 53A-4797 to 8886 look at page #90. I'm referring to the 7H1330 shaft and 4M1189 gear.

Old wrote:

If you have the parts manual for 53A-4797 to 8886 look at page #90. I'm referring to the 7H1330 shaft and 4M1189 gear.

Thanks OM, I see that in the parts manual. What should I be looking for while in there? Broken teeth? FYI, I was pretty surprised by the lack of metal on the magnetic bevel and clutch compartment plugs when I drained and refilled those. There was only a slight amount of metallic sludge on each plug. I know I am being optimistic but I am really hoping that I have no other issues other than worn brake linings.

Just do a visual inspection of the gear and shaft. Look at wear pattern on the gear, any signs of cracking on the shaft. Since you keep asking there is one more check you should make. There should be no lateral movement of the shaft that the bevel gear is mounted to. Get a pry bar in there and check it out.

Knowing working on a loader brakes and steering is much more standing on your head than just a dozer or ag tractor, it pays to do more testing. Reading your question again, what level of knowledge did the previous owner have? He may have already got the steering out of adjustment.

Different but the same trouble, with a 9u D6. The Throw out bearing on the steering clutch was going out. The steering lever felt like if you could pull it just a bit more it would release. So the operator started turning on the external linkage. After steering clutch was fixed took a good bit more to it all adjusted right. It is possible that is where you are, if things have been adjusted by someone not knowledgeable to do so.


So before taking things apart, put the bucket in the ground and get the tracks to spin. Then step on pedal and see if you use the steering clutch is releasing and stopping the spinning on each side. If not then you do need to read the adjusting procedure and see if you can get it without a more experienced mechanic. Having 2 thing to adjust at the same time can be 4 times the trouble in my experience.

Another thing to take into consideration the brakes work better after the oil is warmer (I have never run a wet brake tractor, but sat thru many BS sections of complaints about wet brakes not working until warm).

Old wrote:

Just do a visual inspection of the gear and shaft. Look at wear pattern on the gear, any signs of cracking on the shaft. Since you keep asking there is one more check you should make. There should be no lateral movement of the shaft that the bevel gear is mounted to. Get a pry bar in there and check it out.

Will do, thank you for the info

Ray54 wrote:

Knowing working on a loader brakes and steering is much more standing on your head than just a dozer or ag tractor, it pays to do more testing. Reading your question again, what level of knowledge did the previous owner have? He may have already got the steering out of adjustment.

Different but the same trouble, with a 9u D6. The Throw out bearing on the steering clutch was going out. The steering lever felt like if you could pull it just a bit more it would release. So the operator started turning on the external linkage. After steering clutch was fixed took a good bit more to it all adjusted right. It is possible that is where you are, if things have been adjusted by someone not knowledgeable to do so.


So before taking things apart, put the bucket in the ground and get the tracks to spin. Then step on pedal and see if you use the steering clutch is releasing and stopping the spinning on each side. If not then you do need to read the adjusting procedure and see if you can get it without a more experienced mechanic. Having 2 thing to adjust at the same time can be 4 times the trouble in my experience.

Another thing to take into consideration the brakes work better after the oil is warmer (I have never run a wet brake tractor, but sat thru many BS sections of complaints about wet brakes not working until warm).

Thanks for the reply. The guy I bought the 977H from had no prior experience with it. He is a scrapper who bought it at auction and then tried to fix it up a little to sell. He mentioned to me that he adjusted the brakes, so I think there is a good possibility that he may have messed something up. FYI, I did check the clutch adjustment spec. The manual calls for a 3/16 gap between the steering clutch piston and the roller. The gap was exactly 3/16 on each side. I will try the trick of planting the bucket, spinning tracks, and then disengaging the left and right clutch to see if the track stops. Being that I get slight turning\braking to the left I was kind of thinking the clutches may be ok and that I might just have a braking issue. The left and right brake pedals are currently bottoming out completely when depressed but I can still adjust the left brake adjuster some more. I  just haven't done so yet. The beast is sitting with a mechanic right now that hasn't had a chance to look at it yet. If I don't hear from him soon, I will go tinker around with it some. 

something to remember too magnetic bungs only catch ferrous material you can still have metal particles from bronze and brass components. and other non metallic items that still forms worlds best grinding fluid with lubricants. hence why many things have filters.