450c pinion seal??

[Idaho jarhead]

Hi again, hoping to get some more good advice here. I recently bought a 450c dozer and finally welded some square stock in the final drive plugs to get them out and found the left side was over full and possibly slightly pressurized. I'm assuming this can only be the pinion seal between steering clutch and final case and will require removal of track and sprocket to get to pinion bearing quill? Anyone know if this could all be done from outside the cases or will I need to get into the steering clutch case also?. What I can't determine from my TM 1102 is weather the seal can be removed and reinstalled from outside, anyone know if there is a flange or seat or something in the steering clutch casting that would prevent this. Just wanting to have a complete plan before i tear into things. I'm planning to break the tracks to do some UC work later this summer any thoughts on waiting till then? I guess the seal could be ruined from excessive bearing play, and be wearing the pinion and bull gear, but I haven't noticed any steering or drive problems and was hoping it wouldn't be a bad idea to just wait unless other indications of something more serious present themselves. Thanks for reading, and any advice on any of it.

[pondhogvt]

Congratulations on your dozer purchase,, 450C and 450D are some of my favorite JD dozers.. the only way of replacing that seal is by removing the final drive from the dozer... it goes in from the backside of the case.. quite simple really except getting to it..

I hate to give this type of advice but if you really are going to tear it apart this summer.. for real!!.. too much oil in the final case is not all that bad of a scenario.. it won't hurt anything.. the key would be to try to check and make sure the pinion bearing is not going to pieces on you,, as that could be the cause of the seal leaking by.. bearing movement could have torn the seal...

you would still have to split the track and pull the sprocket to get to the triangle pinion cover to look in there.. you can't check the preload on those pinion bearings with the case on the machine,, but you could pull out the pinion and check the bearings and look for obvious failure signs.. check teeth on pinion and bull gear for example.. and with a flash light you will see the seal behind the bearing race in the case..

at that point you would have to determine wether to keep going or stop.. depending on what you see... by this point you have done a fair amount of work and it would not take much more to keep going and fix,, your call

If I was 100% sure it was just a seal I would just run it... it's the not knowing that can cost you money.. good luck Mark.

[Idaho jarhead]

Thanks for the information Mark, not sure why I assumed the seal was in the steering clutch housing, but knowing it goes in from the back of the final case is a big help. My pessimistic brain was thinking it's not inconceivable that I might have to pull the pinion, then the clutch pack and do the seal from inside the steering clutch housing. Do you have any tips or advice on breaking and relinking the track? I've done it on my excavator which is quit a bit bigger, but it was a horrible nightmare. Thanks again for the info and advice.

[jtrichard]

First i am NOT very familiar with 450S BUT i thought that the later "C"S had a common case? and the early ones did NOT? but you could drill between the cases and make then all common? JUST a thought

[Idaho jarhead]

Thanks for the reply. I only seem to be over full on one side and since i dont have a serial # i dont know if mine came as a common sump or has been converted. Someone please correct me if I'm wrong, the way I understand the common sump on the later C models is that the two steering clutch housings and the tranny are connected, but not the final drive case? My manual describes the conversion of earlier c's due to a couple seals and bleed hose from hydraulic clutch pack no longer being available. When these fail you have no choice but to convert to common sump. From what I've seen in my TM the bleed hose is removed and fluid is returned to the tranny case thru the same passage once the fluid level gets high enough in the steering clutch case, I think it maybe takes some extra fluid in each steering case. Any input on whether I'm understanding this correctly would be welcome.

[pondhogvt]

you guys are right about the newer 450C's having a common sump..

but correct me if I misread the post,, you asked about the final drive being overfull... the common sump only applies to linking the transmission housing and steering clutch housings to equal oil levels.. not the final drive..

if oil is getting overfull it is coming from the seal letting steering clutch oil into the final case...

as I said before not all that bad a thing, too much oil.. it could be the opposite No oil.. oops... best luck Mark.

[Idaho jarhead]

Thanks for the reply, you read correctly I was asking about overfull final drive case. I'm understanding the common sump the way you described it thanks for the confirmation. One thing I'm not sure about is draining the tranny to clean the screen in the front compartment. If im understanding my tm correctly The tranny capacity is 8 gals and each steering clutch case is 7 gallons. I'm guessing the from the fact that there are two tranny drain plugs and the way I understand it the connection between tranny and steering case is kinda high that I won't need to be ready to catch all 22 gallons of hyguard from the entire system, but does anyone know how much I should be prepared for if I only pull the front plug? Thanks for any advice.

[NWJD fan]

When I drained my 450C I got approximately equal amounts from the transmission and both clutch housings combined. So be ready for about 10-11 gallons from the transmission 5 or 6 gallons from each clutch housing. My machine had 2 drain plugs on each clutch housing. The upper fwd plug drains a pocket in the housing. Not a lot comes out of the upper plug but there was a fair bit of water in this location.

[NWJD fan]

Forgot to mention my 450C is 1980 model year with common sump.

[NWJD fan]

When I drained my 450C I got approximately equal amounts from the transmission and both clutch housings combined. So be ready for about 10-11 gallons from the transmission 5 or 6 gallons from each clutch housing. My machine had 2 drain plugs on each clutch housing. The upper fwd plug drains a pocket in the housing. Not a lot comes out of the upper plug but there was a fair bit of water in this location.