Locked up and nowhere to go

[J_J]

Yes, we have already come to that conclusion. That is the first time I have seen a picture of all 4 hoses, and you knew this all this time, and never told anyone.

Carl. Not all wheel motors have case drains. I think you would have noticed if the motors had 4 hoses attached. I have three hoses on mine, and one of them is a case drain.

I found this also.

Integrated Holding Brake For New Hydraulic Motor | Diesel Progress North American Edition | Find Articles at BNET

 

[ponytug]

On my 1445 motors (brand? model?), the brake line is the line that runs through a separate tunnel outboard to a right angle fitting located outboard. You can see the tunnel in Woodlandfarms' photo.

The case drain runs from a port adjacent to the power fittings, near the center of the motor.

Woodlandfarms' photo of his 1845, is of a different motor type. (Mine don't have a "B" stamped over one port.)

All the best,

Peter
P.S. JJ-the Sauer-Danfoss design in your link is basically what Terry at PT has described to me, but Eaton and White also make similar motors.

Perhaps I am seeing things but there appears to be a hydraulic hose (vertical) visible in th picture behind the large hoses to the wheel motor. If it is in fact a hydraulic hose it might be the case drain and the small hose going to the upper part of the motor could be the brake hose.

 

[ponytug]

Two week post repair follow up:
PT repaired the spring plunger on the charging valve, commenting that an internal pin was bent.

PT was nice enough to repaint mine. Good thing that I had a photo of how the hoses connect.

The repaired unit has worked flawlessly for two weeks now, and appears to have been the source of the problem.

All the best,

Peter

 

[woodlandfarms]

Peter, we have warned you time and time again to not open the charging valve and bend the pin. When will you learn?

So, just how do you bend one anyway?

 

[ponytug]

OK Carl, I will try to keep my fingers out in the future...

Short of opening up the valve and messing with it, I have to stretch to come up with ideas;

a) you could have some debris in the channel which bends the pin (hard to imagine)
b) a bent pin could have been installed at the factory (hard to explain why it took so long to seize up)
c) the pin could have been defective, e.g. with a defect that worsened with time.
d) PT had a bad run of charging valve pins
e) PT had a bad charge of the pins on the run
f) the 5.6 quake we had shook something loose inside the charging valve
g)...
​

I did unbolt the unit to install the drain upgrade that routes the oil blowby back to the tank, rather than letting in drool on the floor. Perhaps I knocked something loose in the process; I certainly didn't drop it during the process.

The center bolt in the two metal straps that restrain the hood when open came loose once. The free straps could have been tapping on the outside of the spring, but the spring showed no wear or signs of impingement.

Terry had no ideas that he mentioned.

Personally, I filed it under the "Strange stuff that happens..."

All the best,

Peter

Peter, we have warned you time and time again to not open the charging valve and bend the pin. When will you learn?

So, just how do you bend one anyway?

 

[woodlandfarms]

You kill me. Good answers. I think the 5.6 makes sense.

What is interesting is that my system failed as well when I put in the dribble drain. I hadn't really thought of it until you said something.

Do you have the High pressure filter before the Cumulator or did they drop that design?

 

[ponytug]

I don't have a high pressure filter; I asked Terry about adding one and he didn't think that I should as it was unnecessary, and I leaned hard on the idea of putting one in. I think that they dropped the design a year or two after your unit.

All the best,

Peter

You kill me. Good answers. I think the 5.6 makes sense.

What is interesting is that my system failed as well when I put in the dribble drain. I hadn't really thought of it until you said something.

Do you have the High pressure filter before the accumulator or did they drop that design?

 

[woodlandfarms]

The more I look at the my PT the more I think that the High Pressure filter is a good idea. I am not sure how they work (Do they really filter 100% of the oil or just skim bypass) - seems hard for me to see how 3000PSI and X-GPM could get a quick cleaning in such a small filter.

Anyway... I know my fliter caught debris from a dying hose. In the long run it did not save me from having to rebuild the accumulator, but it may have helped.

 

[ponytug]

The more I look at the my PT the more I think that the High Pressure filter is a good idea. I am not sure how they work (Do they really filter 100% of the oil or just skim bypass) - seems hard for me to see how 3000PSI and X-GPM could get a quick cleaning in such a small filter.

Anyway... I know my fliter caught debris from a dying hose. In the long run it did not save me from having to rebuild the accumulator, but it may have helped.

Carl,

I think that it is a cost/benefit tradeoff. The filter might remove some fine debris at some point, but it has to be balanced with the permanent cost of the work done to force the oil through the filter (HP) and the frictional loss (heat), and the overall impact.
Clearly, I couldn't come up with a reason to ***** Terry's advice for this tractor. YMMV...
In your system, with the amount of debris that you have dealt with over the years, I wouldn't be rushing to take out the filter.

(Do you have all of your hoses switched now?)

All the best,

Peter

 

[J_J]

The more I look at the my PT the more I think that the High Pressure filter is a good idea. I am not sure how they work (Do they really filter 100% of the oil or just skim bypass) - seems hard for me to see how 3000PSI and X-GPM could get a quick cleaning in such a small filter.

Anyway... I know my fliter caught debris from a dying hose. In the long run it did not save me from having to rebuild the accumulator, but it may have helped.

Carl,

What circuit is the filter located. If it is located in the steering circuit, then it is filtering only when you use a certain function, and at other times, it is doing nothing. If a portion of that fluid is going to your brakes, then a piece of crud could cause big trouble. There are times when running the PT that no filtering is going on.