Nagging hydraulic leak

[brin]

OK Jim....fingers crossed byt nooooooooooooow I caaaaaaaaaaaan't type too goode.

 

[jinman]

OK Jim....fingers crossed byt nooooooooooooow I caaaaaaaaaaaan't type too goode.

Thanks Bob.:laughing: I checked the system pressure this morning and it is a skosh above 2400 psi at 2000 rpm. Since each shim raises pressure around 150 psi, I'll leave that alone. Better to be 100 psi low than over-pressured.

 

[wdchyd]

but I just remembered that I tightened the flange down the first time with the o-ring out of place.

You just said something very important........flanges torqued down with seals out of place will distort (bend) the flange.....

I know it sounds unlikely but try putting just a plain oring in between two steel plates, stick them in a press and squeeze, and you'll see the results.....

The flange with only two opposite bolt holes on the long side is your weak spot.......

I'm sure you found the trouble......Good Luck..:thumbsup:

 

[jinman]

You just said something very important........flanges torqued down with seals out of place will distort (bend) the flange.....

I know it sounds unlikely but try putting just a plain oring in between two steel plates, stick them in a press and squeeze, and you'll see the results.....

The flange with only two opposite bolt holes on the long side is your weak spot.......

I'm sure you found the trouble......Good Luck..:thumbsup:

Yep, I have been thinking my bending the tube some was the issue, but just remembered doing that with the seal as I was typing my response to you this morning. The realization of what it caused just hit me. The 4-bolt flange on the pump end seems bulletproof, but the 2-bolt flange is not very forgiving. That's a lesson that cost me $112 plus several remove/install cycles. For me, the frustration was worse than the cost of a new tube. My mistakes usually cost me lots more than that.:laughing:

 

[thclimer]

Hey Jim,

Glad to hear you are back running again and hopefully with no leaks for a long, long time!

Tim

 

[tawilson]

I had to replace the same/similar pipe on my 2120 a few years back because it rubbed against something and wore a hole through. I think it was more than $112, though. Course it is painted blue.

 

[jinman]

Thanks Tim, Tom, and everyone for your help and ideas in this thread. I've certainly got my fingers crossed, but I believe my real problem has been found. As I was finishing up the job, my wife came out to check on my progress. I showed her the problem and she even moved the remote lever to raise the dump trailer while I watched for leaks. When I thanked her for her help, she said, "I didn't do anything." I told her just because she was interested and gave me moral support, it helped a lot. That's the way I feel about all the good wishs here. Everyone's ideas and interest help me a bunch. Thanks!

 

[big lar]

jinman, I have had the same problem with my TC45DA Only put on 75 hours or so per year; had it 3 years before I had any problem, then o ring blew out every 30 or so hours; makes quite a mess like you said.

Tractor supply and auto parts store o rings lasted 30-40 hours; new holland only 6-8!! I have a Caterpillar dealer nearby so recently went there and had him match the size but with higher pressure tolerance, once I start haying, we'll see how that works out.

Yeah its peculiar that the flange has 4 holes but the plate has only 2; my new holland dealer has no explaination as to what is causing the o ring blow out; he recently checked my hyd pressure and its was perfect.

I don't think I ever bend the tube like you think you did, but may have since I do bush hog with it The o ring seems to only blow when I am disk-mowing or bush hogging; seemingly never when baling of scooping snow.

Perhaps the usuage of the hydalics does something, adding pressure or whatever.

It is a mystery and a terribly inconvient and expensive problem!

 

[jinman]

It is a mystery and a terribly inconvient and expensive problem!

As was suggested to me, I'd lay a good straight-edge across that small flange to make sure it is still flat. Even an over-sized o-ring could cause the flange to bend and give you a permanent gap even when tight. Using big grade 8 flat washers also spreads the pressure of the bolts across the flange.

If you have removed this tube several times, you know how hard it is to get to the bottom bolts on the hydraulic pump due to to bolt head interference with the loader sub-frame. My dealer sold me new bolts with smaller (14 mm) hex heads that are much easier to install. Of course, the bolt and threads are the same as the original bolts, but only the hex head is smaller.

Knock-on-wood, my new tube installation seems to have cured my problem. I hope your current o-ring holds and you never have to look at it again. But, if you do, you might consider checking that flange for flatness and adding the flat washers. I'd put at least two on each bolt. It's a bit of a pain with the stud at the top, but you can put two washers on there and still have room for the nut and lockwasher. With the nut loosened, you can slide that U-slot on the flange right under the flat washers and tighten it all down.