I have an early 80's CAT D3B dozer. It has sat a while, now I have a drive issue. When I parked it a year ago, I do remember the right and left sides "acting" a little different. This machine has the two levers and two brake pedal set up. At first I thought I had a brake holding up, but now I wonder. This is what happens, with blade up and moving forward, if I pull back left lever and apply left pedal, left track stops and I turn left, perfect. Now on the right side I pull back on lever, push brake down and slam, whole machine stops. It is almost like the lever is not disengaging the drive clutch, but the brakes are working. Both hand levers feel the same. The foot pedals are a different story. The left travels much further easily and the right has shorter travel and is much stiffer. I removed the panels and have applied WD40 several times on all visible moving parts, no difference. Has anyone run into this before? Any ideas or help would be appreciated.
Wet or dry clutches? I have a question is this a wet or dry system?
i'm sure a few other guys have more experince on them then me. but off the top of my head it sounds like you have a frozen clutch. if yours is the same as my D3B it would have dry clutchs
I just assumed it had wet clutches, but upon further investigation, they started on the D3C. So that most likely is the problem. Anyone have an opinion if this repair is easy or a nightmare? Thanks.
There was an update kit to make the clutches run in oil instead of being dry. You can find lots of D3Bs with wet clutches. If you pull the plug on the bottom of the compartment you will know right away if its wet on not. You problem sounds like the release mechanism is not working at all. I seem to recall a cylinder in that compartment that pushed a release lever. You should check steering pressure when operating that lever. They will drop for a second or so and then climb back to set pressure. If there is no pressure when you pull the lever you problem might be hydraulic. Are there any leaks? You will have to consult a book for more info. It has been a bunch of years since I have been into one of those machines. It is not a difficult job to open that compartment up and look inside. Good Luck!
D3B wet clutch upgrade
From the info you have given, it sounds like the steering clutch release bearing on the right steering clutch is bad. I have come across this problem many times. I would first check the hyd. press. at the cylinder. There is a small plug on the outside of the rear frame near where the sprocket is. If you have good pressure then you will need to pull the cover and check it out. That bearing is easy to replace, you just have to pull the steering clutch to do it. If that is what you end up doing, I would dissassemble the steering clutch and make sure all the discs and plates are good, and check for broken springs.
Lonestar Cobra is that the bearing on the clutch yoke? Thanks
It sounds like the linkage to the steering is disconnected or the valve spool is stuck. As I recall there is a cylinder in the steering clutch compartment that might be bad, the hose feeding it might be leaking inside the compartment or the cylinder might be unhooked from the linkage. The wet clutch conversion was just installing new brake linings that were compatable with oil and filling the compartment half way up with oil.
Thanks John, I jumped on this thread when I saw you mention the wet clutch conversion. I always wondered if that could be done, and now that I know it can, I'll do it when my dry clutch pack finally gives up the ghost.
It is where the yoke connects to the steering clutch.
I am going to go out on a limb here, but I will bet from this machine sitting you have rust built up in the drum splines and the drive disk's are stuck, so it acts just like you have the lever pulled back. The disk's are not engaged.
another D3B question Hi all. First let me apologize for hijacking another topic, as a new member I can't start threads yet. ( Mods if you could move this to it's own thread I would thank you very much). I just bought my first dozer it's an 87 D3B. while going over it before use I found alot of play in the blade bushings and that several of the pins have been spot welded in place. I have decided to remove c-frame and blade to rebuild it while I have it clean. What is the best way to do this. I noticed that the hoses coming from the blocks on either side to the c-frame have one long hose and the other has about a 12" hose coupled to a longer hose. I am assuming this setup allows you to split the union connect the short hose back to the block and connect the remaining long hoses together to seal both systems, is this right. Any help or suggestions before I start this is welcome even if it's not something I asked. Thanks Greg
If you have to pull the steering clutch it is not that bad of a job.
Check the short Rod that acts off the Cylinder for clearance, these little Dozers are not built to a Tight Tolerance and often with only a small amount of Wear on the Clutch Pack, the rod is left with no running Clearance, I have done a few of these Little Bangers with steering faults, if you find the Rod is tight, ether grind a bit off or get shortend as you like, but try to keep a nice Ball end to it,I have spent a few Hours Measuring the Main Frames and found some very uneven work, the Brake Drums I think are D4, and so are lots of the Clutch Plates. tctractors
D3B overheating after 1 hour Mod 27Y Radiator ,Fan,etc has been replaced--NO contamination in oil or coolant. Head and gasket reworked. Any ideas?
Mod 27Y Radiator ,Fan,etc has been replaced--NO contamination in oil or coolant. Head and gasket reworked. Any ideas?
D3B overheating after 1 hour -------------------------------------------------------------------------------- Mod 27Y Radiator ,Fan,etc has been replaced--NO contamination in oil or coolant. Head and gasket reworked. Any ideas?
did you power wash the rad? some fans blow backwards plugging the rad from the inside.
how about the "T" stat ?