our 1969 case 580b hydraulics quit working while trenching. HELP

[scatterfrats]

We are not familiar with where to start with diagnosing. The previous owners let things run down quite a bit, but we felt the price was right for our needs so bought it traveling through two states to pick it up. Back to the problem at hand: We checked to see that the input shaft on the front mounted pump was turning: IT WAS. Hyd fluid was low so topped it off! Don't know where to start with checking out the pressure from the pump. With the engine running I pulled the plug on the top of the filter and fluid poured out, but was easily stopped with just a soft thumb pressure. I am NOT familiar with how much pressure there should be or how to check any hydraulic pressure anywhere in the system. Would love to hear from someone with a working knowledge of this machine Thanks in advance.

 

[Tinkerer]

Have you checked the Hydraulic filter ? Better yet put a new one in it. Could be an internally collapsed suction hose to.

 

[Tinkerer]

When you remove the hydraulic filter be very careful and cut it open so you can flatten the folded pleats. The chances the are you will find a lot of silver crap in it. That would indicate a pump failure.

 

[Tinkerer]

I replied to your PM. Basically I said --->
Did you figure out what the problem is yet ? I failed to mention that just because you can see the flex coupler turning on both sides of the rubber bushings does not mean that the splined shaft on the pump isn't stripped and the input shaft is not turning.

 

[Billrog]

Its common for those splines to go.

 

[mikebramel]

Yeah definately check the splines. Gear pumps typically don't just quit like that with internal reasons.

 

[Ronsii]

X3 on the splines, it may look like its turning and may actually be until under load. did it make a slight a slight grinding noise after it quit?

 

[Swampfoxo]

We are not familiar with where to start with diagnosing. The previous owners let things run down quite a bit, but we felt the price was right for our needs so bought it traveling through two states to pick it up. Back to the problem at hand: We checked to see that the input shaft on the front mounted pump was turning: IT WAS. Hyd fluid was low so topped it off! Don't know where to start with checking out the pressure from the pump. With the engine running I pulled the plug on the top of the filter and fluid poured out, but was easily stopped with just a soft thumb pressure. I am NOT familiar with how much pressure there should be or how to check any hydraulic pressure anywhere in the system. Would love to hear from someone with a working knowledge of this machine Thanks in advance.

 

[Swampfoxo]

The filter on the right side by the lift chyinder. The gauge as well should be in the green. Ard both hyd resouvoirs full left and right side should fill it till it comes out the ovefflow plug hole left side

 

[Welder Dave]

NEVER check for hydraulic leaks with the engine running or even stopped with your hands. The potential pressure can penetrate the skin and cause poisoning or worse.

 

[scatterfrats]

THANKS for your great info everybody! Sorry we have not replied to all your inputs before, but stumbling around with the forum buttons, we quite accidently found your messages about three minutes ago. Again, our deepest apologies! Computers are another thing that are not our specialty at all at 75 years. We are in the mountains and must travel a 90 mile circle to get to a McDonalds to get on Wi-Fi. We are on it out of sheer necessity!
We haven't started taking it all apart yet as it's still mounted on the machine, HAPPY DAYS, and the parts have not been ordered as yet.
Will try to post after we've had a chance to look it over closely through all of your glasses.
NOTE: There was a "strange whirring sound" that started at the same time the hydraulics suddenly quit working which left the backhoe bucket with a load of rocks and dirt at the bottom of the trench. Up until it quit it had been a wonderful brutishly strong workhorse exceeding all of our wildest hopes!
LOVE THIS THING and IT'S NEEDED BAD so have got to see it through whatever ailments it might come up with!

 

[Walker1]

I am guessing either the splines on the shaft or the pump vanes. Other possibility would be relief valve. Where does the whirring sound come from?

 

[scatterfrats]

Hi, thanks! It was the pump spline and the coupler. Thanks again.

 

[scatterfrats]

TO EVERYBODY, I don't know if our novice computer messages ever reached all of you who responded to our backhoe HELP plight, but THANKS AGAIN for all the great input! We are waiting for the new pump and coupler to arrive later this week, so by God's Grace, we have high hopes of seeing this wonderful machine to return to the work of setting up a new mission base/farm here in the beautiful forested mountains of northern New Mexico! scatterfrats

 

[Steve Young]

Have you checked the Hydraulic filter ? Better yet put a new one in it. Could be an internally collapsed suction hose to.

Is there a procedure to find an internally collapsed hose? It is suspected that this is the problem I'm having.

 

[Delmer]

Is there a procedure to find an internally collapsed hose? It is suspected that this is the problem I'm having.

What issues are you having? that would be a logical place to start.

 

[Steve Young]

It's a 225 Cat excavator. We had catastrophic failure of the left pump ( controls swing and left track). Since the repair, the gasket in the rebuilt pump keeps blowing out. The dealer thinks it's being caused by a collapsing hose.

 

[Tinkerer]

[QUOTE="Steve Young, post: 723780, member: 65581" The dealer thinks it's being caused by a collapsing hose.[/QUOTE]
Maybe, Steve. Maybe not. A pump usually starves for oil on the suction side of a pump when a hose collapses. It would be almost impossible for a hose to collapse on the output side of any pump. Have you checked the pump pressure yet ? Might be waaay too high. Does it make any noise before the gasket blows out ? Might be a warped pump housing from improper torque values on the body of it.

 

[mitch504]

also, a 225 should have pressure on the oil tank. maybe a clogged filter?

 

[mitch504]

did you do you do a thorough cleanout?