B1700 Hydraulic Leak

[jonness]

I bought a 1998 Kubota B1700 with 115 hours on it (looks like new). However, I was dumping a heavy load of dirt in a tight area while turning the front wheels really sharp (near the edge of a bank), and afterward I noticed a lot of hydraulic oil spilled onto the ground.

I looked under the tractor and saw a pretty good amount of oil around the rear of the front transmission, just under where the steering column is.


So I took the mat off the deck and noticed a lot of oil had collected underneath it.


I removed the instrument panel and shroud so I could get to the steering components.


I noticed the oil seemed to be coming from the right side. I suspect the leak is coming from the cover with the four bolts on the right side of the steering column (shown below) but I'm still uncertain. This appears to me to be the "most likely" suspect.


Is this a common problem area for 1998 Kubota's, or is it possible there's a leaking seal up underneath the steering column where I can't see? I find no external oil up high. It's all down low on the right side. The tractor was garaged it's entire life and has very low hours. It's difficult for me to imagine a gasket would already be leaking this much oil (about 1/4 cup in perhaps 5 minutes of heavy pressure on the hydraulic system while sharply turning the wheel). Also, nearest I can tell, the relief valve is designed to divert the oil to the reservoir as opposed to spilling it out onto the ground. Is this correct?

Thanks

 

[North Idaho Wolfman]

I'm thinking you need to dive in deeper as I would suspect a hose or fitting before I would suspect the cover plate.

 

[jonness]

Hmmm, you could be right. The first photo shows oil that pooled in the top of the nut. This indicates the oil probably drained down from above the nut. In addition, the oil dispursed in all directions once it made its way to the deck. This explains how it got on the transmission case below the deck.


Other than the gasket for the side cover, there are two steel hydraulic lines above the nut. I'm thinking my first course of action should be to pressure wash all the oil off the machine. Then tighten the flare nuts as tight as I can on the two steel hydraulic lines above the nut. Then put the tractor back together and run it in order to see if the leak stops. In addition, I should rig up a pressure tester and see what the hydraulic pressure is set at.

 

[1970cs]

Yes clean every thing up and wipe things down. Leave that area exposed and run the tractor in place and turn the wheel to lock and hold left and then full right. I would believe that if it is the lines, it should show up.

Pat

 

[jonness]

I found that my power steering inflow line is broken off at the tip where it fits into the collar. It's part number 6C042-39220, which is listed online as discontinued. However, it's available with a 7-day lead time for $115.00. How difficult/expensive is it to have one of these made locally? Is it possible to somehow braze the tip back onto the steel line? Would there be a downside to having a flexible hose made instead of the steel line?





Thanks

 

[North Idaho Wolfman]

The steel line was actually fitted into the fitting then welded on, a butt weld of that fitting won't hold.

That is a discontinued P/N the new P/N is H6C00-39202

Buy online now for $50 +7.84 shipping
http://www.ebay.com/itm/Genuine-Kub...641766?hash=item1c65a8bde6:g:p4YAAOSwPe1UKuSS

 

[jonness]

Thanks for your reply.

Looking closer at my pipe and the one on eBay, they both use straight ends with flare nut sleeves as opposed to the pipe ends being flared. Since mine broke perfectly at the edge of the old sleeve, I might be able to just use a new sleeve.

Then again, there's probably a reason it broke. I read a thread where another b1700 owner went through 4 of these pipes, due to excessive movement of the pipe. I've seen a couple of posts discussing the possibility of changing the problematic pipe for a flexible hose in order to better absorb the vibration.

Interestingly, the pipe on eBay is mislabeled and is actually a slightly different pipe. It's really 6C040-39222 instead of 6C042-39222. It's still in production and costs $41.15 at the online dealers. I saw another post that said it's the updated version with fewer bends and replaces all earlier versions. I'll see what Kubota says in the morning, and if they don't have it in stock, I'll see about getting one made by my local hydraulic shop.

 

[jonness]

I went to the main two hydraulic shops in my town today. Both places were unable to make the power steering line, because it uses metric fittings. So I took it to the Kubota shop, and they said they can't make one because it's a steel line. They only make hoses. I asked if they could make a hose as a replacement due to the design flaw in the steel line causing frequent breakage in this model of tractor. They said the line needs to be steel because it's "high pressure," and a hose will blow in this application. I asked about a double-braided hose, and they said it would not be flexible enough to bend tight enough to fit this application.

They located two different lines (depending on which one correlates to my serial number) that are 2 weeks shipping and handling away. One is $60, and the other is $150 (inc. tax and shipping). I'm unsure which one I will need to buy, as I didn't have my serial number handy while there. Either way, I'm not thrilled about having my tractor down for 2 weeks while I wait for an expensive part to arrive that has a design flaw that is sure to break again in the near future.

I asked at the hydraulic shops if I could simply reuse the compression fitting as a temporary fix while I wait for my new line to arrive. The line is long enough and would still work if I could just get the compression fitting. Unfortunately, they indicated the compression fitting is not reusable.

Apparently, there's no way to engineer a long-lasting solution, and a near-term fix is not possible.

 

[jonness]

North Idaho Wolfman:

Once I learned how to read the symbols (in the parts manual) showing which parts fit which serial numbers and which parts are interchangeable with other parts, I realized the part you linked does fit my tractor. Also, it's the more expensive part that would cost me $150 from my local dealer and $115 + shipping from an online dealer. So I ordered the eBay part. According to the manual, it will fit. It looks quite different than the stock line. Apparently, it's an upgraded version with less bends. I confirmed via the auction that the part number is indeed 6C042-39222. So it looks like now I just need to wait until the part arrives.

thanks to everyone.

 

[jonness]

I received and installed the part. No more leaks!