Needing a Dual Pilot Operated Check Valves for a toplink?

[SylvainG]

Hi, I have a brand new valve with an internal leakage specs at

INTERNAL OIL LEAKAGE
4 ÷ 8 cc/min	From A B to T

My hydraulic toplink didn't come with a Dual Pilot Operated Check Valves and adding one would cost more than what I paid for the toplink. Not sure I understand the leakage specs above. The toplink would be used to control the tilt of my snow blower and box grader. Is the check valve a waste of money for my scenarios? Thanks.

 

[/pine]

FWIW...by disconnecting the hoses from the quick disconnects there is no place for the oil to go...

 

[SylvainG]

True, but then, I might as as well kept my mechanical toplink if I have to get off the tractor to reconnect the QCs to operate the cylinder

 

[oldnslo]

Sylvain
That leakage spec is based on a given pressure differential and oil viscosity so without knowing how long you want the top link to hold position under what pressure it is difficult to say yes you need check or no you do not need check.

 

[/pine]

True, but then, I might as as well kept my mechanical toplink if I have to get off the tractor to reconnect the QCs to operate the cylinder

Normally...unless you are using a sophisticated laser guided leveling tool or something...the typical bleed down will be insignificant for typical applications of most 3ph implements...
...And besides...with t&t you can make minor adjustments on the fly...

 

[Tinhack]

Surplus Center used to sell a kit to add a pilot operated check valve to a cylinder but I can't find it any more. It came with banjo fittings mounted on 3/8" tubing. You had to cut one tube to length, flare it and make/buy the fittings for the cylinder port. I guess it was too complicated for most DIYs.

You can still get a like check valve on Amazon for $44 but you have to provide the rest of the hardware. (Tubing, banjo fittings and cylinder port fittings.) The part comes from Holland (the country). I bought my 3-valve remote kit from them and it was high quality stuff. You'll get your order in 7-10 days.

 

[RickB]

FWIW...by disconnecting the hoses from the quick disconnects there is no place for the oil to go...

For what it's worth there's nothing stopping a disconnected cylinder from drifting towards extension if oil can bypass the piston seal and external loads are applied in that direction.

 

[SylvainG]

Surplus Center used to sell a kit to add a pilot operated check valve to a cylinder but I can't find it any more. It came with banjo fittings mounted on 3/8" tubing. You had to cut one tube to length, flare it and make/buy the fittings for the cylinder port. I guess it was too complicated for most DIYs.

You can still get a like check valve on Amazon for $44 but you have to provide the rest of the hardware. (Tubing, banjo fittings and cylinder port fittings.) The part comes from Holland (the country). I bought my 3-valve remote kit from them and it was high quality stuff. You'll get your order in 7-10 days.

That seems what I was looking for. Princess Auto also sells the check valve but once you add the custom cut hoses and fittings, it costs the same as the toplink itself

Normally...unless you are using a sophisticated laser guided leveling tool or something...the typical bleed down will be insignificant for typical applications of most 3ph implements...
...And besides...with t&t you can make minor adjustments on the fly...

My reasoning is I just don't want the snow blower to bleed and start digging in the gravel. I'll give it a try with the box grader which in my opinion where the bleed would be the worse (most stress on the toplink).

 

[TMGT]

This is the valve tinhack was referring to, just be aware the tubing is metric and the banjo bolts are BSPP so might not be as easy to adapt to your cylinder. The fitting coming out of the valve block are part of the valve assembly and are for the metric compression fitting making them harder to adapt to SAE fittings.

Check Valve /Tubing Kit For 8" and 11" AMA Top-Link Cylinders 05165 | Repair Kits | Hydraulic Parts & Accessories | Hydraulics | www.surpluscenter.com

Check Valve /Tubing Kit For 8 and 11 AMA Top-Link Cylinders 05165, Repair Kits, REPLACEMENT TUBING AND CHECK VALVE FOR AMA TOP-LINK CYLINDERSAMA,05165 ,

www.surpluscenter.com

 

[Tinhack]

That's it! And you don't even have to flare the tube--It uses compression nuts.