Hydraulic pump noise on 8N

[Southernspeed]

1951 8N. If I have any weight on the three point, when I lift it up I get a kind of knocking/ratcheting noise. It lifts ok, but the noise is there (not there with nothing on the three point)
Is that a normal noise? It's fresh oil in there and when I had the trans apart I cleaned what little sludge was in there. It seems to operate ok but will go down over a couple of days with a 50lbs (approx) trailer hitch frame on there.

 

[oldnslo]

Is there an external suction line to the hydraulic pump? If yes I would check all the connections to make sure there are no air leaks.

If this front mounted pump driven by crank shaft check that drive coupler and key are not damaged and slipping under load.

 

[TractorTech]

What oil did you use? Gear oil is correct, 80w90.

 

[Southernspeed]

What oil did you use? Gear oil is correct, 80w90.

90w mineral oil from NAPA. Level is good too.

 

[Southernspeed]

Is there an external suction line to the hydraulic pump? If yes I would check all the connections to make sure there are no air leaks.

If this front mounted pump driven by crank shaft check that drive coupler and key are not damaged and slipping under load.

No, no suction line on these, it’s an immersed pump.

 

[EdGooding]

1951 8N. If I have any weight on the three point, when I lift it up I get a kind of knocking/ratcheting noise. It lifts ok, but the noise is there (not there with nothing on the three point)
Is that a normal noise? It's fresh oil in there and when I had the trans apart I cleaned what little sludge was in there. It seems to operate ok but will go down over a couple of days with a 50lbs (approx) trailer hitch frame on there.

Your pump is worn as most N pumps get. As long as it is working, leave it alone. The scotch yokes have a bit of play. If it is raising/lowering properly and holding for a couple of days, I would ignore it and continue to use it until it starts not operating properly. Parts are available to rebuild your pump if you want to spend the time and money. There is a test port on the pump, on the lower, right side that you can connect a pressure gauge to test it. I've got a procedure and specs around here somewhere if you want to pursue that.

 

[Southernspeed]

Your pump is worn as most N pumps get. As long as it is working, leave it alone. The scotch yokes have a bit of play. If it is raising/lowering properly and holding for a couple of days, I would ignore it and continue to use it until it starts not operating properly. Parts are available to rebuild your pump if you want to spend the time and money. There is a test port on the pump, on the lower, right side that you can connect a pressure gauge to test it. I've got a procedure and specs around here somewhere if you want to pursue that.

Well I certainly like the idea of just leaving it alone!
I’d be interested in putting a gauge on there out of curiosity if you can find the info, if not I’m sure I could dig it up online somewhere, unless it’s in the manual? I haven’t looked.
Thank you.

 

[EdGooding]

Well I certainly like the idea of just leaving it alone!
I’d be interested in putting a gauge on there out of curiosity if you can find the info, if not I’m sure I could dig it up online somewhere, unless it’s in the manual? I haven’t looked.
Thank you.

 

[John0829]

Ed's right leave it be and 9 out of 10 chances something else will fail before the scotch yokes. The pump is submerged in oil, plenty of lubrication, so short of oil contamination wear of the pump will be minimal.

 

[Southernspeed]

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Thank you. As always, much appreciated!
I’ll have to check my pressure gauge, not sure it goes that high.