3 pt. won't stay up

[Anonymous Poster]

3 pt. won\'t stay up

A couple of weeks ago, I changed the hydro fluid in my 1980 B7100D. I've always (for the year I've had the tractor) had a problem with 3 pt. leakdown until the thing got warmed up, which I attribute to a leaky seal in a valve in the hydraulic system. Since changing the fluid (I used 80w90 gear oil, the manual calls for 80 weight), the lift goes up and down, but won't stay up no matter how long I use it. I happenend to look in the tranny case, and noticed that the oil was very foamy, and had turned yellow. Is this a sign of water in the oil? If so, how could it have gotten in there? If it is water, how do I get rid of it when I change the oil again? Should I use UDT instead of gear oil?

Thanks for your wisdom.
Chris in SW VA

 

[Thomas]

Re: 3 pt. won\'t stay up

Chris,
My operator's manual for my B7100 says ownly to use Kubota UDT....universal transmisson hydraulic fluid,and they even listed the part number.
Part number. 70000-20002
Also the manual show the only place you add gear oil SAE80 will be front differental case (4WD)...Front wheel gear case left & right (4WD)...Steering gear box.

A friend of mine who work for Caterpillar told me once " use the recommend brand names on your equipment it will save you time and money in the future"

I have heard if the wrong hydraulic fluid or a substitute was use once the fluid warm up it would foam also lose of pressure.

Hopefully only once you will have to drain the system,than add the fluid with a new filter.
Might also be a good time to replace that seal.

Take care and good luck.


Thomas..NH

 

[W5FL]

Re: 3 pt. won\'t stay up

If it were my tractor, I would drain the hydraulic fluid, chage the filter, completely refill with Kubota UDT, run it for 5 hours, drain it and change the filter and refill with Kubota UDT. Gear Oil has no business in the hydraulic system. In the front axle - maybe, but not in the transmission/rear axle. /w3tcompact/icons/frown.gif

 

[Cowboy]

Re: 3 pt. won\'t stay up

I could not have said it any better myself Wen.

Chris...You can do your tractor and yourself a favor by staying with manufactures spec's for all Hyd. and gear oils. as for engine oil...somebody tell the man. /w3tcompact/icons/smile.gif

Cowboy
BigBoyz Toyz

 

[Chris]

Re: 3 pt. won\'t stay up

Cowboy: thanks for your response, but I am confused by it. You say you agree with Wen (gear oil has no place in the hydraulic system) but you also say to stick with manufacturer's specs (which call for gear oil). Really, I'm not making this up. I have quoted previously chapter and verse from the manual and have heard from other older model owners on this board that theirs, too, list gear oil for the tranny/hydraulic system. I am inclined to try the UDT anyway, even though it goes against the recommendations in the manual.

Thanks again, Chris

 

[Chris]

Re: 3 pt. won\'t stay up

wen: thanks for the response. No disrespect intended, as I have a lot of respect for the posters on this board (and I asked for opinions), but if gear oil has no place in the hydraulic system, then why is it spec'd in the manual for that purpose? I have heard from other older model owners in the past that their manuals also specify the gear oil. I am inclined to try the UDT, but I have another question. Your post (and another one) mention changing the filter. I don't see any filter for my tranny/hydraulic system other than a couple of strainers that I cleaned during the change in queston. My manual and parts lists don't reference any filters for this system, either. Since this is an older model (1980) is it possible that the specs and design (adding of filters) have changed in the ensuing 20 years?

Thanks, Chris

 

[Chris]

Re: 3 pt. won\'t stay up

Thomas: thanks for the reply. I assume that your B7100 is a good deal newer than my 1980 model. I'm going to try the UDT, but I'm wondering if the specs have changed over the klast 20 years as my manual specifies the gear oil. Thanks, Chris

 

[MChalkley]

Re: 3 pt. won\'t stay up

Chris, I wouldn't put UDT in it, if it calls for gear oil. Are you sure there's not something mechanically wrong as well?

Mark

 

[Chris]

Re: 3 pt. won\'t stay up

Mark: It's certainly possible that the leaky seal I mentioned in the original post is simply leaking more, which causes the lift to fall. I also have the problem of the fluid being yellow and foamy, and I am just speculating that the problems are related. Thanks, Chris

 

[Bird]

Re: 3 pt. won\'t stay up

Chris, is that 1980 model a hydrostatic transmission or a manual. I don't know anything about the ones that old, but like the other guys, I never heard of using gear oil in a hydraulic system, but at the same time, I think I'd stay with what the manual says unless I was sure it was a misprint. And my 1995 B7100HSD had a spin on filter under the little console between your feet. (I mention it because another guy once told me he had bought a B7100 with no manual and someone told him he ought to change the filter, but he'd never been able to find it and asked me where mine was).

Bird