# Long 510 3PT Bouncing



## Matt299 (Apr 30, 2019)

Hello all. I’ve spent a lot of time reading posts and learning on this forum but now I need help. My dad has a Long 510 and the 3pt has started “bouncing” all of the sudden. It drops about an inch and then returns to the previous position only to repeat this again and again at a very fast pace. At low rpm it is less noticiable but at 1000rpm or higher it shakes the tractor. We have changed filters and fluids but it has not improved. I’ll try to upload a video but I’m wondering if anyone might know where I’d start in diagnosing? It will bleed down rapidly (with the tractor off and the leaver up). Any ideas?

thanks!


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## ovrszd (12 mo ago)

For some reason the 3pt lift cylinder is losing pressure. Might be a controller problem. Especially if you are saying it just suddenly started doing this? Might even be a position control linkage issue, something coming unfastened in the linkage under the seat? Check all of the external linkage before going any further.

Most common problem is the lift cylinder is leaking past the seals. This lets the 3pt "bleed" down. Then the Position Control linkage catches it and raises it back to it's correct position. This can be slow, taking a few minutes. Or it can be fast as cycle every few seconds.

A way to check the cylinder for leaks is to put a load on the 3pt in the raised position. Shut off the engine. If the cylinder is leaking the load will immediately start dropping. Severity of cylinder leak will determine speed of drop.

I'm not completely familiar with the tractor model. But this should apply. The lift cylinder, lever linkage and upper 3pt arms should all be attached to the top cover, under the seat. Will be a rectangular cover with a dozen or so bolts. 

Remove seat. Disconnect lift links from the upper arms. Remove the ring of bolts. Lift the entire cover off the top of the tractor housing. The cylinder is embedded in the underside of the cover. 

This is a heavy item that's best removed with a cherry picker.

You'll need a shop manual or a good shop mechanic to educate you on how to rebuild the cylinder. You'll need a good source for parts as well.


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