3 pt. question

[s19438]

if the capacity of a TO series hydraulic system is 700/800 lb. how then can the system lift a 2000 lb. tractor by usuing the ferguson tractor jack ?

 

[Inno]

Two reasons as far as I can tell.
1. The jack is a lever which gives it a mechanical advantage and 2. it is not lifting the full weight of the tractor, some of the weight is on the front support.........at least that's how I see it based on a youtube video I watched.

 

[Jeff-oh]

The three point does not lift the full weight of the tractor as a dead weight. The downward weight of the tractor is still carried by the jack.

The 3-point uses it's 700lb and leverage to rotate the tractor up onto the tractor jack.

This had to do with the CG discussion below. The tractor jack slids forward of the rear axle. The lift is aft, thus the force multiplier of this leverage works. The beauty of Ferguson Engineering.

FYI: The Ferguson Crain is a real slick implement as it can out lift any modern boom arm. The is because Ferguson put a pivot link on the crain that increases the lifting capasity due to geometry.

 

[s19438]

once the tractor is on the jack must the tractor engine be kept running or can the jack support the tracor on its own.

 

[S2710]

If you shut the tractor off the 3 point will creep down like with any other imp. You will have to chain up the three point so it doesn't drop when you shut off the tractor.

Bob

 

[John(UK)]

Just leverage thats all it takes....John(UK)

 

[John(UK)]

We used a couple in our paintshop and we had a large wooden block ( like a railway sleeper only slightly smaller) that was longer than the crossbar of the jack was off the groun by about 6", we then cut out a piece on one end so that the hydraulics would drop about 2" and the crossbar was on the "shelf" that was cut out of the Block. There was no chance of it dropping..John(UK)

 

[Frank(Aust)]

Give me a lever long enough and a fulcrum on which to place it, and I shall move the world.
Archimedes

 

[John(UK)]

Frank, Let me know when you are going to do that and I will come to watch..John(UK)