Hydraulic oil in the transmission

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Plug Nickel
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Hydraulic oil in the transmission

Post by Plug Nickel » Tue Jul 02, 2019 5:20 pm

Hello,
Been lurking for years but something came up today that caused me to register and ask all you good folks a question.

Insofar as crawlers these days, I have a 450C as well as a straight 555. Went to use the 555 to set a 48” culvert today and found that all my hydraulic oil now resides in the transmission of all things.

I know the 450C much better than the 555 and not knowing where the hydraulic pump is and speculating that it could be direct coupled to the transmission I thought that perhaps the pump seal went out?

Before digging in to this, does anyone have any thoughts as to how the hydraulic tank could drain into the transmission?

Thank you,
Mark

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Jason37756
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Re: Hydraulic oil in the transmission

Post by Jason37756 » Wed Jul 03, 2019 1:20 pm

I'm not familiar with the 555 at all, but most dozers have a resoviour under your right arm with the pump mounted on the front of the motor. If this is the same setup as your 555 then it's not related to the oil in the transmission.

Just to clarify you are not confusing the clutch housing with the transmission are you? Every clutch housing I've been into have been dry, but are only separated from the transmission fluid by an oil seal. If that seal breaksdown then oil leaks forward into the clutch housing.

jason
Last edited by Jason37756 on Thu Jul 11, 2019 7:19 am, edited 1 time in total.

Jim B
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Re: Hydraulic oil in the transmission

Post by Jim B » Wed Jul 03, 2019 7:05 pm

I am not sure but from looking at the parts catalog, I am thinking the 555 hydraulic pump is convertor housing or transmission mounted, so the shaft seal leaking in it could get oil to the transmission. Hopefully one of the fellows with or familiar with the 555s will post a better answer. If you don't have a pump under the radiator, driven off the crank, under the floor boards is the likely place to look for it.

Do you have a set of manuals for it? if you don't you should be getting a set (technical and operators), as they are different from your450C.

Plug Nickel
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Re: Hydraulic oil in the transmission

Post by Plug Nickel » Wed Jul 03, 2019 8:41 pm

Thank you,
Unlike my 450C, the hydraulic pump is not off of the crank on the front of the engine so I’m guessing it’s on the transmission.

Coinciding with the loss of hydraulic oil (and no leak on the ground), the transmission dipstick under the seat is showing oil eight inches or more above the full mark while running.

I just ordered a parts and service manual today so I should get a good idea where the leak could be but still guessing it’s the pump seal.

The pump is still strong though when I bought the machine six years ago there was a lot of neglected maintenance including really dirty fluids so I can imagine that a seal might have gone south.
Just hoping whatever it is ain’t a booger to get to…

Gotta say, the 450C is a lot less complicated; would rather of had a machine without the torque converter and all the other stuff like my Allis HD3, but I guess time moves on.

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Jason37756
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Re: Hydraulic oil in the transmission

Post by Jason37756 » Wed Jul 03, 2019 10:09 pm

With the given pump location I'd say your on the right thought process...hopefully it'll be somewhat easy to repair.

Jason

newwood
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Re: Hydraulic oil in the transmission

Post by newwood » Wed Jul 10, 2019 7:36 pm

Mark-- Well, I get the same thing happening on my 1010, which has the hydraulic pump located in the front. Oddly it happens even when not being run, so on my machine it doesn't seem to be related to the high pressure part of the pump, but manages to leak into the transmission just under gravity. The hydraulic pump is run off the transmission, and there are seals between the two systems so I suspect that's what's bad on mine (and perhaps yours), but there wasn't much enthusiasm for that theory on the Early Model JD Crawler board when I posted the question. For the moment, I just keep filling with hydraulic (which can take up to a gallon), but I'll have to start draining off the transmission (mine too is way over the top): for the moment looks like more pain to fix than to replace fluids. I'll be interested to hear how you sort yours out.
jt
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Jim B
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Re: Hydraulic oil in the transmission

Post by Jim B » Thu Jul 11, 2019 6:09 am

newwood,

Plug Nickel's 555 is a totally different animal from your 1010 in drive arrangements for the hydraulic pump and transmission.

I don't think it is lack of enthusiasm, on the other board, as much as everyone is at a loss to figure out how the two can be tied together. Your 1010 has a hydraulic pump for attachments (blade) mounted under the radiator and driven from the front of the crankshaft doesn't it? That hydraulic system is supposed to be totally separate from the transmission and reverser. Oil from that hydraulic system should not get to the transmission; unless someone has done some engineering on their own and made something for a cross tie on your machine; which only you can find by physically studying the machine. I doubt that has been done or you have more issues. I believe you do have a pump (in or on the reverser) for the hydraulic reverser oil system, which is totally separate from the hydraulic system for attachments. Are the oil levels in both the transmission and reverser increasing? Reverser oil to transmission I could see possibly happening. I may be wrong on these points and hopefully someone will correct my errors if so. I don't have the 1010 manuals (other than access to the on line parts catalogs), but you said in another post that you have the shop and owner's manuals. Do you have the John Deere SM2034 service manual for the 1010 crawler or is your shop/service manual a different publication? That manual should have some schematics of those systems in it. You can study the manuals to see if you can pinpoint where there might be a tie you can check out next time you are at the machine. Just my best thoughts at present.

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Re: Hydraulic oil in the transmission

Post by Lavoy » Thu Jul 11, 2019 8:55 am

Hyd pump on a 1010 is crankshaft driven off of the front of the engine and is in no way connected to the transmission, so any transfer of fluids from one of those systems to the other is utterly impossible barring some ungodly modification to one or the other or both.
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newwood
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Re: Hydraulic oil in the transmission

Post by newwood » Thu Jul 11, 2019 4:52 pm

Of course, Lavoy is right. It is indeed driven off the crankshaft so even if the pump leaked at the crankshaft seal it wouldn't end up in the transmission. I still can't explain why my hydraulic fluid goes down while my transmission fluid goes up but I'm now suspecting an evil crawler elf. I'll have to sit out with my shotgun and see if I can catch them in the act.
jt
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Plug Nickel
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Re: Hydraulic oil in the transmission

Post by Plug Nickel » Sat Jul 13, 2019 10:13 am

I guess at least I’m lucky I don’t have an elf problem. Mice in the battery box yes, but no elves.

I did get the service manual and it seems that the pump seal is the only route for the hydraulic oil to get into the transmission as you all suspected.

Unfortunately it’s on the bottom of the transmission so I’ll have to crawl it up on timbers and drop the belly pan to get at it unless of course I can find a gynecologist turned mechanic that can do it all through the muffler.
Hopefully I can keep the pan on the hinges and use it as a recliner.

Got too many irons in the fire to get to it for a few weeks, but has anyone changed the shaft seal on this pump?

‘Course you never know what you’ll find until you get it out, but I’m wondering if I should pre-purchase a “seal kit” for that pump or should I just get the number off the seal when I pull it?

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