Third Functions Hydraulic Fittings Difficult to Engage

[RNeumann]

Heat expansion is a non issue. 99.9% of the time the fluid is warmer when in use then outside air temperature will ever be. So typically you are uncoupling and reconnecting the ends when the fluid is over outside air temps. But by the off chance the implement builds some pressure over time the simple act of uncoupling the two implement ends relieves the few drops of pressure.

Unless their is some physical limitations I’ve never had or seen an issue coupling or uncoupling that was on the implement side.

You seem stuck on this one. What process are you using to store your implements? I’m just not seeing how a few degrees of fluid temp change is cause the inability to cycle the QDs.

 

[ovrszd]

Heat expansion is a non issue. 99.9% of the time the fluid is warmer when in use then outside air temperature will ever be. So typically you are uncoupling and reconnecting the ends when the fluid is over outside air temps. But by the off chance the implement builds some pressure over time the simple act of uncoupling the two implement ends relieves the few drops of pressure.

Unless their is some physical limitations I’ve never had or seen an issue coupling or uncoupling that was on the implement side.

You seem stuck on this one. What process are you using to store your implements? I’m just not seeing how a few degrees of fluid temp change is cause the inability to cycle the QDs.

Assuming you are addressing me?

I'm not stuck on anything. I'm just offering advice.

So right now my Kubota is sitting in the machine shed with the Grapple on. It's somewhere around 30 degrees in the machine shed. I want to haul some gravel with my smooth bucket. I crank up, drive outside, uncouple the Grapple and drop it on the ground. I couple the hoses together.

Today is a sunny day with expected high of 55F degrees. This afternoon when I want to reattach my Grapple I am going to have problems. Not with the tractor. With the Grapple. Uncoupling the Grapple hoses will not release anywhere near enough fluid to release the pressure that will be there due to heat expansion. It will be so extreme that I probably won't be able to recouple the Grapple hoses to themselves. I have flush couplers. I will have a very aggravating situation.

If you've never experienced this you must rarely switch 3rd function attachments?

 

[Fallon]

My experiences match oversized's

 

[ovrszd]

My experiences match oversized's

Sucks doesn't it.....

 

[the old grind]

..I expected him to cover heat expansion. Just following the guidance (Ted) gave does nothing to solve that problem. Also coupling the hoses together does nothing to solve the heat expansion problem either.

Didn't think it was just me who noticed that right away. My fluid doesn't get hot very often, rarely warm that I can tell, I'd think the cyls might be warmer after uoing a grapple (either one) and they always seem `body temp at my level(s) of working 'em.

My experiences match oversized's

Mine too, .. so far, .. in five years of switching out a grapple(s) two-three times/year.

(Got three other FELs. One of those will also get SSQA & diverter upgrade.)

 

[npalen]

Wonder why we don't see any thermal relief valves installed on 3rd function attachments or any hydraulic attachments for that matter? They are a simple T-shaped fitting that lets a tiny amount of fluid bleed off if the pressure rises beyond a preset point. Have seen them on farm machinery.

 

[Fallon]

Wonder why we don't see any thermal relief valves installed on 3rd function attachments or any hydraulic attachments for that matter? They are a simple T-shaped fitting that lets a tiny amount of fluid bleed off if the pressure rises beyond a preset point. Have seen them on farm machinery.

Generally I expect thermal expansion pressure would be less than normal operating pressures. That would mean those would leak everywhere every time the impliment was used. Unless you are talking about a manual bleed or drain valve rather than an automatic relief valve.

 

[ovrszd]

Generally I expect thermal expansion pressure would be less than normal operating pressures. That would mean those would leak everywhere every time the impliment was used. Unless you are talking about a manual bleed or drain valve rather than an automatic relief valve.

Yeah, I doubt that thermal expansion ever gets close to operating pressure.

I've never tested this, but I suspect 100psi would prevent reattaching a coupler. Versus 2,500psi operating pressure.

 

[ericm979]

I've also seen the couplers locked up due to an ambient temp rise of a few tens of degrees. Drop the grapple at 50 degrees and pick it up at 70 and I can't get its couplers uncoupled.

I'm going to make pressure release gadgets to plug into the hydraulic implements. Each will have a coupler set, some pipe fittings and a valve. You use the valve to open the system to the outside and relieve pressure. The idea came from some thread here.

 

[ovrszd]

I've also seen the couplers locked up due to an ambient temp rise of a few tens of degrees. Drop the grapple at 50 degrees and pick it up at 70 and I can't get its couplers uncoupled.

I'm going to make pressure release gadgets to plug into the hydraulic implements. Each will have a coupler set, some pipe fittings and a valve. You use the valve to open the system to the outside and relieve pressure. The idea came from some thread here.

I think if you often have problems this is the ideal solution!!!