[GWT3046r]

Here is a short video showing how top and tilt works. This is setup on my 2018 John Deere 3046r tractor and replaces the top link and right adjustable link on the three point hitch. I hope this explains how to use Top and Tilt and you can see what it might be helpful to have on your tractor. My version is being controlled with an electric diverter valve which redirects flow from the loader functions to the 4th and 5th valve. Thanks for watching!

Click here to watch on YouTube

Otherwise, view below.

 

[jgayman]

If the diverter channels hydraulic flow away from the loader, what prevents the bucket from eventually bleeding down and scraping on the ground when the Top 'N Tilt is being used?

 

[GWT3046r]

If the diverter channels hydraulic flow away from the loader, what prevents the bucket from eventually bleeding down and scraping on the ground when the Top 'N Tilt is being used?

I would imagine the hydraulic fluid already present on either side of the cylinder holds its position once the hydraulic circuit is closed off and redirected. Just a guess.

 

[jgayman]

I would imagine the hydraulic fluid already present on either side of the cylinder holds its position once the hydraulic circuit is closed off and redirected. Just a guess.

If it does, it would be the first JD SCUT/CUT tractor in history to do so.

 

[Jim Timber]

That's a lot of extra hose out back.

 

[Auguste]

Thanks for the informative post.

 

[Ray_PA]

If it does, it would be the first JD SCUT/CUT tractor in history to do so.

It is possible, depending on the type of hydraulic cartridge used in the diverter, the ports that are not used when the diverter is shifted are pretty much closed. If the FEL ports are are tightly closed by the diverter, then it will not leak down.

Solenoid controlled cartridge valves normally have less internal leakage, and some have check valves in them so they have no internal leakage, so they provide a more positive lock on the hydraulic accessory. I don't know is this diverter has this capabilities, I am just throwing out a possibility. I guess if it doesn't, you would have to shift the diverter back to the FEL and raise it routinely. :dunno:

It would be like disconnecting the FEL quick connects. If the hose fittings are actually blocked, the FEL will not bleed down.

The reason the FEL or any other cylinder attachments leak down, isn't due to the attachment itself, it is due to the internal leakage in the SCV on the tractor.

Having the solenoid controlled diverter in line after the SCV, this diverter could provide a more positively closed valve than a standard SCV. Don't know, but maybe. :dunno:

 

[GWT3046r]

If it does, it would be the first JD SCUT/CUT tractor in history to do so.

I guess if you're asking if the loader just drifts down, then I haven't noticed that. However, in the applications I'm using it in so far, I'm don't remain in the "engaged" diverter mode for long. I have needed to use my loader functions, so I switch back to loader functions after a few minutes. I'll report back if I notice issues with drift.

 

[Jim Timber]

It is possible, depending on the type of hydraulic cartridge used in the diverter, the ports that are not used when the diverter is shifted are pretty much closed. If the FEL ports are are tightly closed by the diverter, then it will not leak down.

Solenoid controlled cartridge valves normally have less internal leakage, and some have check valves in them so they have no internal leakage, so they provide a more positive lock on the hydraulic accessory. I don't know is this diverter has this capabilities, I am just throwing out a possibility. I guess if it doesn't, you would have to shift the diverter back to the FEL and raise it routinely. :dunno:

It would be like disconnecting the FEL quick connects. If the hose fittings are actually blocked, the FEL will not bleed down.

The reason the FEL or any other cylinder attachments leak down, isn't due to the attachment itself, it is due to the internal leakage in the SCV on the tractor.

Having the solenoid controlled diverter in line after the SCV, this diverter could provide a more positively closed valve than a standard SCV. Don't know, but maybe. :dunno:

You're over-simplifying this a bit and missing another part of the equation: Air

You have internal leakage around the piston seals, but that's usually pretty minimal unless they're worn or scored from dirty oil. You also have air that gets introduced from cavitation which can lead to sag and sponginess in the mechanism.


Hydraulics are not mechanical holding devices intended to support loads indefinitely. They have internal losses which are compensated for and otherwise simply accepted as part of the beast. I'm actually impressed with how long my rockshaft will support a load when not under power. My loader will leak down much faster. :cheers:

 

[jgayman]

You have internal leakage around the piston seals, but that's usually pretty minimal unless they're worn or scored from dirty oil. You also have air that gets introduced from cavitation which can lead to sag and sponginess in the mechanism.


Hydraulics are not mechanical holding devices intended to support loads indefinitely. They have internal losses which are compensated for and otherwise simply accepted as part of the beast. I'm actually impressed with how long my rockshaft will support a load when not under power. My loader will leak down much faster.

The rockshaft on my 2720 will stay up for weeks even with a 300+ lb implement attached.

Like you, the loader is another story. Based on my own experience and from reading forum posts it seems the problem is much worse on newer JD SCUT/CUT tractors. Folks with older models (650, 750, etc.) report that their loader will stay in position a long time even after the engine is turned off. Whereas folks with newer tractors find they bleed down pretty fast. JD of course has their little bleed-down spreadsheet which clearly shows that the tolerances in their hydraulic components has gotten worse as the years progress.

When I was running a subsoiler back and forth in a field with the bucket slightly raised I was surprised just how often I need to hit the SCV lever to bump the loader back up into position.

 

[GWT3046r]

The rockshaft on my 2720 will stay up for weeks even with a 300+ lb implement attached.

Like you, the loader is another story. Based on my own experience and from reading forum posts it seems the problem is much worse on newer JD SCUT/CUT tractors. Folks with older models (650, 750, etc.) report that their loader will stay in position a long time even after the engine is turned off. Whereas folks with newer tractors find they bleed down pretty fast. JD of course has their little bleed-down spreadsheet which clearly shows that the tolerances in their hydraulic components has gotten worse as the years progress.

When I was running a subsoiler back and forth in a field with the bucket slightly raised I was surprised just how often I need to hit the SCV lever to bump the loader back up into position.

I frequently store tractors with loaders in the raised position. I quickly run out of space with indoor storage and try to maximize it by cramming them in there with raised loaders. I'll be more diligent on which leak down versus those that stay put. I definitely notice that some do and some don't, I just haven't paid much attention to model. Most everything would be 2008 and newer with a handful of exceptions.

 

[Jim Timber]

I wonder if Deere has gone from spec'ing hand lapped valves to precision ground and honed valves? That'd account for a decrease in cost (ground and honed being less labor intensive) and an increase in internal leakage.

 

[firemachine69]

I wonder if Deere has gone from spec'ing hand lapped valves to precision ground and honed valves? That'd account for a decrease in cost (ground and honed being less labor intensive) and an increase in internal leakage.

The fact all compact tractors today have a weak frame design, versus no-frame designs from yesteryear, should clarify any doubt of the cost-cutting measures JD (and all others) have implemented.