Farm Equipment - High hydraulic pressure

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High hydraulic pressure

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Topic: High hydraulic pressure

Posted By: Kraig (WI)
Subject: High hydraulic pressure
Date Posted: 13 May 2010 at 12:21pm

I'm putting a new cylinder on my Disk that will run off either my D17 or WD45 hydraulics. The cylinder is rated for 2500 psi. Is there are pressure reducer that I can put on my system so I don't blow out the seals in the cylinder?

Kraig

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7010,D17D,WD45,WD,WC,WC,B,
Gleaner K,60,66,72

Replies:

Posted By: BobHnwO
Date Posted: 13 May 2010 at 1:05pm

Don't use a low pressure cylinder on high pressure hydraulics,ask me how I know,there may be a way to reduce pressure but I'm not sure!

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Why do today what you can put off til tomorrow.

Posted By: Bill Long
Date Posted: 13 May 2010 at 3:00pm

Kraig, I have to agree with Bob. We had a situation where a person "jacked up" the pressure in a WD hyd system then attached a low pressure loader.

After an oil shower we - cause the rams were pointed at the operator's seat" we pulled the pump and found that he has increased the popping pressure to get more lift.

I know the pressure in the pump cannot be reduced. However, some hyd shop may have a hyd pressure reducer. You want to drop the pressure from 3500 psi - may be a little high - to 2500 psi.

Don't use the hyd without it.

Let us know how it goes.

Good Luck!

Bill Long

Posted By: M Diesel
Date Posted: 13 May 2010 at 5:44pm

If you can't or don't want to change the pop pressure inside your valve body, you can buy pressure relief cross over valves and plumb them into your hoses. Basically it becomes a vent from the supply hose to the return hose. Of course each hydraulic function needs the same treatment, meaning you need one for lift rams and another for tilt rams.

Check with SurplusCenter.com etc.

This is basically what is needed, but the fittings on this one may be a problem.

https://www.surpluscenter.com/item.asp?item=9-7674&catname=hydraulic - https://www.surpluscenter.com/item.asp?item=9-7674&catname=hydraulic

Posted By: AaronSEIA
Date Posted: 13 May 2010 at 6:57pm

Wile others may have first hand experience, I've never had a problem. Have a "low pressure" cylinder on my mower and have never blown it up stroking it out. Didn't on my cultimulcher or the JD disc I pulled. I think my pressure pops off at about 3,200 or so by the gauge I've got installed. It's of course be better putting an AC cylinder on it, but it's not a guarentee to blow one up if you don't.

AaronSEIA

Posted By: CTuckerNWIL
Date Posted: 13 May 2010 at 7:23pm

It is possible to lower the pressure internally on the WD and 45 style pumps. It would be quite involved, pull the pump, remove the by-pass spool and c'bore the 1/4 inch hole deeper. ten thousands of an inch will decrease approximately 700 psi. If you have a shim stack behind the pressure relief spool you can remove shims.
I personally would not do this. You loose way too much when using proper cylinders.
The easiest way would be to add a new valve similar to log splitter valves. They would have an internal pressure relief and could be used for your SOB cylinder and bypassed for a normal high pressure cylinder. Mount the valve where you want it, run a hose from the pressure in side of the new valve to the remote coupling. Then you will have to add a return line to your oil supply, easily done with a tee in place of the drain plug from your hydraulic oil. Now you can run a 2 way SOB cylinder and don't have to worry about spraying oil all over. When you want to use a high pressure cylinder, unplug the new valve from the remote connector and plug in your cylinder.
I have used 2 way Oliver cylinders(acting as one way with a vent) on a disc and a planter with my 45 when it was running about 3500 psi and never had a problem. If you hold position works you can raise it till you implement is out of the ground and put it on hold and you will never blow the cylinder. A good pump hammering at the end of the cylinder stroke without bypassing is hazardous. Also if the company that made the cylinder has it rated at 2500psi you can bet your last dollar it has been tested way beyond that. Charlie

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http://www.ae-ta.com" rel="nofollow - http://www.ae-ta.com
Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF

Posted By: Skyhighballoon(MO)
Date Posted: 13 May 2010 at 8:47pm

Guys we hooked my KT disc up last year to Rick's D19 with a standard 2 way Cross Mfg 3X8 remote cylinder...no problems using it never blew anything up...Rick was just careful to not jam it up against the stops. Mike

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1981 Gleaner F2 Corn Plus w 13' flex
1968 Gleaner EIII w 10' & 330
1969 180 gas
1965 D17 S-IV gas
1963 D17 S-III gas
1956 WD45 gas NF PS
1956 All-Crop 66 Big Bin
303 wire baler, 716H, 712H mowers