Rebuilding the cylinder on my hoe stick

AntrimMan · Nov 20, 2005

Right you are. Stone the high spots off in a cylindrical fashion, not axial. IF YOU SEE THE NICK BEFORE IT FIRST ENTERS THE CAP.
This nick damage is really mostly limited to the cylinders that are close to the work.
The bad thing about rod nicks is that the little bit of oil in them makes the dirt stick and the scraper doesn't clean it off so you end up with a little fine dirt inside the cylinder everytime it is cycled.
You can stone the rod nick to finish the job but replacing it is the best option if it is in a place that continually get splashed with dirt.
Just my opinion. I don't intend to belittle and mean no offense to anyone. I'll drink if you're buying.

All the best,
Martin

EddieWalker · Nov 20, 2005

Rob,

Thanks.

I don't know about a DA, or even what that is. /forums/images/graemlins/grin.gif

On my dozer and backhoe, I just put on the lines, then fire up the engine. No bleeding of any kind. After running the engine at idle a few minutes, I work the contols to the repaired cylinder. It takes a moment for it to respond, but that's about it.

I don't break it in, or do anything fancy, just get back to work and push it as hard as I can. /forums/images/graemlins/shocked.gif /forums/images/graemlins/smirk.gif /forums/images/graemlins/grin.gif

Eddie

Bird · Nov 20, 2005

( I don't know about a DA, or even what that is. )

Now I don't know either, Eddie, but I do know what a DA sander is. /forums/images/graemlins/laugh.gif The DA means Dual Action or Dual Acting, so I'll take a wild guess that it means the same thing on a hydraulic cylinder; i.e., power both directions.

R_Redding · Nov 20, 2005

sorry guys..

I meant Dual Acting as you so rightly deduced.

Rob

Kyle_in_Tex · Nov 28, 2005

( If you talk to your guy, tell him I have a Case 1550 Dozer with the Sundstrand pumps. They are the same pumps used in the John Deere 850 Dozer also.)

Eddie, I talked to my buddy that used to work at the hydraulic shop. He asked what your dozer's symptoms were and I wasn't sure. He said you probably have a main motor connected to the engine and then 2 drive units on each track that convert the pressure back to rotary motion. He said they are very simple pumps and yes, You can scatter them $$$. But, he said, most of the time the plates on the ends either need to be lapped flat or replaced to fix most leakage problems which isn't so expensive.
Kyle

EddieWalker · Nov 28, 2005

Thanks Kyle,

The pumps are working real strong right now. When it's working, it's just amazing. When it's not, it's very,very heavy. /forums/images/graemlins/grin.gif

Just for fun, the dozer has a 500 plus cubic inch straight six motor built by Case. It puts out over 160hp. After the engine is what looks like an oversized bell housing. There's a big gear in there and a shaft. This turns the smaller gears that power the pumps. On the newer models there's a seal in those gears, but my model isn't supposed to have that feature.

That was what I thought was causing the loss of preasure across the board on all three pumps.

The left pump is connected to the left track hydralic drive motor with a dozen hoses or so. The middle pump is for the blade, and the right pump is for the right drive motor.

The pumps are $20,000 each to replace from Case. They said that since I didn't have the seal, then it must be that all three pumps went out at the same time, but only when it heats up. Go figure /forums/images/graemlins/confused.gif

I figured for that much money, I'd run it until it blew up, then either fix it or sell it for scrap. I'm not putting $30,000 into a $25,000 dozer.

After running it for a few days, it seemed to have more power. A few more days, and it really did have more power. Right now it's just amazing at what it can do.

Eddie