Hydraulic side-link idea...am I trying to be too clever?

[mjncad]

As I'm trying to figure out what tractor modification projects I'll tackle this year once it warms up in my unheated garage; I've been thinking about adding a hydraulic side-link to my hydraulic top-link. I have plenty of SCV's available.

Other than the cost of the extra cylinder and the fittings/hoses to make it work; am I trying to be too clever with this idea. Please see attachment that explains what I've got in mind.

Thanks,

 

[radman1]

Nice try, but I do not think it will work. The problem will be because the loads on each side link will most likely not be equal. The cylinder with the most resistance will be the last to move. Only after the other cylinder has completed it's full extension or retraction will the oposite cylinder want to move. It is the same concept with FEL and 2 curl cylinders. The front mount on a FEL either has to be a solid fixed piece of iron (or the bucket acts as a fixed point) or the the curl cylinders would retract or extend at different rates. This will be more noticeable on the rear lift arms.

 

[Trails2004]

Wouldnt a stop block(stroke control sleeve) on the cylinder be much easier and less expensive???
http://www.princehyd.com/Portals/0/products/accessories/catalog/StrokeControlSleeves.pdf

 

[mjncad]

I wasn't aware of those items Trails, thanks for sharing.

The issue is not the stroke length of the cylinder; but the side to side motion that contacts the PB and SCV connectors. I'd like to add tilt; but the offset pivot will just make the matter worse; hence the idea of moving the tilt's pivot point to the tractor centerline.

 

[mjncad]

Thanks all for the suggestion and comments. After reading the advice here and elsewhere, I'm going to shelve this idea as nice in theory; but not practical.

 

[J_J]

mjncad

Could you not extend the tabs on the tractor, that hold the bottom of the cylinder, effectively giving more room for the cylinder to raise, etc. and not touch anything. .

 

[AKfish]

mjncad

Could you not extend the tabs on the tractor, that hold the bottom of the cylinder, effectively giving more room for the cylinder to raise, etc. and not touch anything. .

I did that - more or less - on my last tractor. I drilled 3 holes along the lower link arm that the bottom of the cylinder pinned into. The closest hole had the greatest lift upwards (tilt) and the farthest hole had the least lift change (could pose a problem for the top cylinder).

Don't recommend doing that, however. I had concerns about the overall strength of the link arm and if you forgot what hole (or just wasn't thinking about it at all) the cylinder was pinned in - you could have a problem...

Trails suggestion is the easiest - a clamp on stop block on the cylinder ram. (Do they slip and/or scratch the cylinder ram?)

If you're concerned about interference with the top link - measure and measure again the lift distance and buy a cylinder with a safe stroke length.

Agree with Radman's observations of the inherent problems of "linking" the two side links together. Uneven terrain would make operating a rear blade , etc. nearly impossible.

PS Nice design plan - way too professional for my "bush league" brain, though!

AKfish

 

[Trails2004]

......Trails suggestion is the easiest - a clamp on stop block on the cylinder ram. (Do they slip and/or scratch the cylinder ram?)...

I do not believe so this is a different type Grip-Rite | Cylinder Depth Stop | Stroke Control for Farm Equipment

Always remember to control your stoke

 

[mjncad]

mjncad

Could you not extend the tabs on the tractor, that hold the bottom of the cylinder, effectively giving more room for the cylinder to raise, etc. and not touch anything. .

Interesting idea J_J; but I'm concerned this could somehow introduce excessive stress on those tabs, and I've seen a picture of a broken tab on the same series of tractor as mine. It wasn't pretty and a new 3PH lift housing is $$$$. That's where the tabs on the 4000 series tractors reside.

I think I'll look into doing some sort fitting magic to raise the QD's up and out of the way. If I can, this would probably be the least expensive and troublesome method.

The big problem is that it's tight back there with almost no wiggle room for any kind of slick solution.

Thanks for the suggestion.

 

[mjncad]

PS Nice design plan - way too professional for my "bush league" brain, though!

AKfish

Thanks, I did CAD professionally for 24-years before I got out of the business. Old habits die hard.

 

[Cocre]

It may work, you just need to make a couple of changes (see picture). You will also have to manually fill the rod end of each cylinder and the interconnect hose between the cylinders with hydraulic fluid before assembly. Occasionally you may also have to add oil to compensate for any leakage.

Whatever distance one cylinder moves forward the other cylinder will move the exact distance in the other direction. Just a thought.

 

[dfkrug]

I think I'll look into doing some sort fitting magic to raise the QD's up and out of the way. If I can, this would probably be the least expensive and troublesome method.

This is why I do not like (or usually go with) the factory bulkhead locations
for QD hoses. They get in the way, especially if you mount a hoe. I will
often use NO bulkhead at all....just one or two hoses, connected together
when not in use.

COCRE's method will work to do what I think you want, but the fixed amount
of fluid in your cyls will limit their stroke. The wrong combination of tilt
and 3-pt lift could still hit your obstructions.

3RRL uses 2 cyls for his tilt strategy, primarily to get a LOT of tilt.

 

[dcyrilc]

This is why I do not like (or usually go with) the factory bulkhead locations
for QD hoses. They get in the way, especially if you mount a hoe. I will
often use NO bulkhead at all....just one or two hoses, connected together
when not in use.

COCRE's method will work to do what I think you want, but the fixed amount
of fluid in your cyls will limit their stroke. The wrong combination of tilt
and 3-pt lift could still hit your obstructions.

3RRL uses 2 cyls for his tilt strategy, primarily to get a LOT of tilt.

I was wondering if Rob's setup was going to be mentioned. It was the first thing I thought of while reading.

 

[mjncad]

Interesting idea Cocre and simpler. I'll keep this in mind should I decide to revisit the dual cylinder setup.

 

[gpflepsen]

If you add a couple check valves to one cylinder you don't need to worry about the timing of the cylinders. You can always get them in time by pressuring out in one or the other direction. You can easily bleed them this way upon initial assembly too. I'd recommend giving the cylinders a rod-side admission instead of a piston side. This will reduce the oil pressure in the slave "dummy" trapped oil of the piston side. If you go with piston side admission, you'd need to greatly increase the pressure rating of the rod side circuit components.

If you have a buddy in a hydraulic shop or have the tools yourself, some small ports could be welded to the cylinders to accommodate the check valves.

Please excuse the Paint drawing.