DWCox
Silver Member
Interesting Hydraulics Problem Discovered Today
I had bought my 2005 JD 790 this June with 33 hrs. on it. It had sat in storage by the prior owner a good portion of the time. Today it was finally warm enough to go out and warm it up sufficiently to change the trans./hydraulic fluid. I had been noticing some cavitation in the power-steering when cold, as well as a pause at the bottom of the stroke when dumping the bucket, so I was hoping this would cheer it.
I always check my fluid levels, so I was a bit shocked when only about two quarts of fluid came out upon opening both drain holes. Puzzled, I then opened up the main cap only hear a whooshing sound and see fluid pouring into my large pan (I use a portable masonry pan to catch large quantities like this all at once). I immediately pulled the breather tube only to discover that it was not breathing at all. Apparently, a mud-dobber or something had built a nest and I had never even suspected it was plugged, though this is not the first time I have seen this happen. It just didn't cross my mind.
I have since cleaned the screen (which did have some small metal shavings) and changed the filter. I have a feeling that the bucket hesitation and cavitation problems will be gone.
I had bought my 2005 JD 790 this June with 33 hrs. on it. It had sat in storage by the prior owner a good portion of the time. Today it was finally warm enough to go out and warm it up sufficiently to change the trans./hydraulic fluid. I had been noticing some cavitation in the power-steering when cold, as well as a pause at the bottom of the stroke when dumping the bucket, so I was hoping this would cheer it.
I always check my fluid levels, so I was a bit shocked when only about two quarts of fluid came out upon opening both drain holes. Puzzled, I then opened up the main cap only hear a whooshing sound and see fluid pouring into my large pan (I use a portable masonry pan to catch large quantities like this all at once). I immediately pulled the breather tube only to discover that it was not breathing at all. Apparently, a mud-dobber or something had built a nest and I had never even suspected it was plugged, though this is not the first time I have seen this happen. It just didn't cross my mind.
I have since cleaned the screen (which did have some small metal shavings) and changed the filter. I have a feeling that the bucket hesitation and cavitation problems will be gone.
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