NH TC40 Hydraulic Pump Question

[podagrower]

My worklife (and brother in law) have kept me from having any real tractor time over the past year. Yesterday was a the first day I really needed the tractor in a couple of seasons and that's when the trouble started. No lift or rollback for the front end loader, and lots of noise from the hydraulic pump. The hydraulic pump has been getting nosier over the past couple of years, but I did not realize what was making noise until I had no hydraulics. Machine has less than 100 hours on the latest filter and fluid, and was down less than a gallon. I did buy it used with 1600 hours and do not know the maintenance prior to purchase. I replaced the fluid and filter with hope that it was a minor issue, fluid was clean, but there were unidentifiable chunks in it-not metal parts, but something soft and sludge like. Once the air bled out of the system, the loader worked great, and the pump was quiet-for about 5 minutes.

This morning, again, I have almost no loader hydraulics. I can hear the pump, and it will "spurt" fluid, which can be felt in the loader joystick and a change in torque on the motor. I'm assuming I need a new pump, but looking at the parts diagram, I see a strainer in the sump before the filter. Is it possible for the strainer to plug up, starving the pump for fluid and cause the surging? As I type it, I'm leaning towards no, but I can hope, right?

The next question is, would you rate changing the hydraulic pump as a DIY activity?

 

[TractorTech]

You may have a plugged strainer not knowing the history of the tractor and having soft, sludgy pieces in the oil. Since the pump is upwards of $500-750., I think it would be worth looking at the strainer before you buy the pump, but definitely before installing a new one.
As far as replacement of the pump, it is fairly simple. Just make sure you buy new orings for the pump lines and pump to case.

 

[podagrower]

So the mystery deepens/continues. I was thinking about the 3 point hydraulic system. I can't tell from the repair diagrams where the 3pt picks fluid up from, but it would have to run thru the same strainer and filter (in my thinking). So if the loader doesn't work, but the 3pt does, it's the main hydraulic pump, right? If they both don't work, it's the strainer or some sort of obstruction?

The deepening of the mystery is that when I started up the tractor to test this theory last night, the loader hydraulics worked fine. The pump is plenty noisy, but not as loud as when the loader isn't working.

 

[dave1949]

Partial connections in the loader quick connect couplings can cause strange stuff. You may have other things going on, but I would disconnect then reconnect the loader lines "just because." It's free.

 

[TractorTech]

The loader and 3pt run off of the same system, but like Dave said you could have something with the couplers on the loader. The other thought could be the 3pt doesn't require the flow of the loader cylinders to operate. When you say the 3pt is operating properly, the pump doesn't make any noise? Does the 3pt operate smoothly? Also, the pump could be worn causing the noises and intermittent loader ooeration.