Starting repairs and trouble shooting new to me splitter

[rwhite]

Figured I would start a new thread. I purchased a used 20 ton brave splitter. From what I can gather here is how it was equipped OE:
5hp briggs (been replaced with new 5hp briggs)
11 gpm 2 stage pump
4"/24" stroke piston paperwork says rebuilt 6 mo ago
4.5 gal hyd tank
Return line filtered
Bought for $350. When I bought it the guy stated the control valve was bad. But he had the old one but it wasn't hooked up (Energy brand valve). Got home and hooked the valve up. It split fine but extend and retract was erratic. I pulled the detent cover off and the large ball bearing had popped out. Reseated everything and it worked great for 5-6 strokes then started being erratic again. Detent ball again popped out. One other thing to mention is the detent cover was full of fluid. IIRC these are supposed to stay fairly dry. In addition I noticed the detent cover was cracked (cheap aluminum). The cracked cover, leaking, and erratic control seemed to confirm the valve was bad so I ordered a new one (haven't got it yet). So to my 1st questions:
1. I can't find any info as to the presets for the original relief valve. The new one is capable of 3500 psi but I'm not sure of the preset either. If I understand correctly the pump is capable of 3000 psi. What should I set the relief at? This is the advice from an oldtimer I know;
Install the new valve and if it works good and doesn't kill the motor, leave it alone. If the motor dies under pressure start backing off the relief 1/4 turn at a time (keeping count) until the motor stays running.

Thoughts? @triptester , @Jags or anyone else that may have more hydraulic sense than me.

 

[Jags]

A gauge in the system is the only accurate way. Pretty cheap parts to make that happen. You will want to keep the relief pressure set BELOW the weakest rating of the components. If all parts are matched at 3000 psi I would go for a 2750 relief setting to start with.

 

[rwhite]

A gauge in the system is the only accurate way. Pretty cheap parts to make that happen. You will want to keep the relief pressure set BELOW the weakest rating of the components. If all parts are matched at 3000 psi I would go for a 2750 relief setting to start with.

I'm assuming I'll need to plumb the guage on the output side of the valve and that pressure should no exceed 2750. If I check that then move to the input side it should exceed 3000 which I think is the unloading pressure of the pump.
Sound right?

 

[Jags]

Not quite. The valve is an open center type. The valve simply passes fluid through it till you redirect it to the cylinder. The easy way to do this is with the gauge on the "push" input to the cylinder. Then dead head the ram and read the pressure.
Note: for safety reasons u should be very cautious during the first dead head as you don't yet have any idea where the relief is set.

 

[Jags]

Whoops. Rereading your last post...yes I think you have the idea right but you really only need to be concerned with the push pressure. The rest will follow suit.

 

[rwhite]

Whoops. Rereading your last post...yes I think you have the idea right but you really only need to be concerned with the push pressure. The rest will follow suit.

Thanks. I'll get a guage and get it plumbed.

 

[rwhite]

Looks like another trip to town! I don't have any hyd fittings to plumb the gauge. Using galvanized doesn't seem like a good idea (IIRC correctly it's only rated around 300 psi)

 

[Jags]

Good call.

 

[TreePointer]

Looks like another trip to town! I don't have any hyd fittings to plumb the gauge. Using galvanized doesn't seem like a good idea (IIRC correctly it's only rated around 300 psi)

Correct. In addition to pressure considerations, also note that many dedicated hydraulic fittings are manufactured with a high precision such that they don't require any sealant. (This is why they are more expensive.) For those that require sealant, do not use teflon tape; use a HIGH TEMPERATURE THREAD SEALANT designed for use with hydraulic fluids and other petro products.

 

[rwhite]

Good call.

I should preface this with, I live in the land of wheat and BIG tractors. Maybe not so much the land of good mechanics? I went to 3 different ag supply house/shops. Including a JD and a Case dealer. Got the gauge no problem. Asked for fittings to plumb it in....all use black steel pipe and had no hydraulic fittings with NPT. Am I missing something? According to them the combines and cultivators run 2700+ psi and this is all they use. The bins that the pipe was in were marked sch 40. Seems pretty dangerous to me working with the nads that close to a fitting not rated for the psi. Ive been cut but i think id like to keep whats left. Think I gotta make a run to the big town for parts.

 

[kevin j]

surplus center has good internet selections.

Cat and JD progbably don't have much NPT as it was phased out many years ago wherever possible. Still most common on consumer stuff, but industrial stuff is JIC/SAE 37 degree flare, SAE or Metric oring ports, SAE 4 bolt flanges, or flat face oring ORFS.

Its not that Sch 40 pipe, or class 150 or 300 fittings will blow up right away. Lot of people will argue they used them for years no problems. But the margin between operating pressure and burst pressure is really close, and any mfg tolerances or cheap quality or water hammer effect can cause a disaster. Hydr fittings are designed to at least 4x service factor.

Yes a hassle, and you will probably never know that you did the right thing because of the accident that didn't happen, but you making the right call. Do it right and be safe.

 

[rwhite]

And there's a BIG difference if a pipe blows on a combine vs 12" away from my crotch!

 

[kevin j]

google oil injection injuries.
They are really bad, and fast. We had a couple at work over the decades.
And that is NOT a location you would want to know how they are treated.

 

[rwhite]

Just patiently awaiting the valve to arrive. Went to the big city today and got all the fittings to plumb the gauge in. Went ahead and just had a new high pressure hose made since I was there and the one on there was likley original. Hopefully that's all I need! I took the chance buying a $350 splitter knowing I'd have to buy a valve. But with the gauge, valve, and new hose I'm into it for $500 now.

 

[rwhite]

A gauge in the system is the only accurate way. Pretty cheap parts to make that happen. You will want to keep the relief pressure set BELOW the weakest rating of the components. If all parts are matched at 3000 psi I would go for a 2750 relief setting to start with.

Happy to report that the splitter runs awesome. Got the new valve and gauge plumbed. 2750 psi was a bit high for the 5hp. It would kill the motor when dead headed. Got it set around 2650 and it will dead head without killing it. Seems to work pretty well. I had 5-6 rounds left that I was having to take the wedge and maul to and it split them without issue. No more left to split so it will sit until spring.

 

[Sean McGillicuddy]

It's always good to hear a good ending!