Advanced log splitter plumbing question

[SemperFiSawguy]

Seems like you have 2 choices to find a suitable valve. Send the p/n of the cartridge to the various mfrs and ask for a comparable valve with the higher cracking pressure, but I wouldn't hold my breath waiting for an answer. Or wade thru the mfrs' catalogs. Eaton(Vickers), Parker, Rexroth, Hydraforce, etc.

Or replace the spring in your valve with a stiffer one.

I ended up finding and ordering a hydroforce PCV16-12T-N
Its a 3.6:1 and 25psi cracking pressure variant with 3/4 ports. Plus it was only $80 new so that works!! It looks like due to other suggestions i will be taking my cylinder back off to weld a couple new bungs on. One for my pilot signal and one for my base port to eliminate adding Ts.

 

[SemperFiSawguy]

Im out here splitting with it right now!! Its working already. Taking the cylinder back off isnt a big deal though to add a couple more ports.

 

[sean donato]

I ended up finding and ordering a hydroforce PCV16-12T-N
Its a 3.6:1 and 25psi cracking pressure variant with 3/4 ports. Plus it was only $80 new so that works!! It looks like due to other suggestions i will be taking my cylinder back off to weld a couple new bungs on. One for my pilot signal and one for my base port to eliminate adding Ts.

You don't really need a secondary port for the pilot signal. I mean it's not gonna hurt anything, but a "T" is all thats needed in that side.
Edit: where did you get the pilot check for $80.00?

 

[SemperFiSawguy]

You don't really need a secondary port for the pilot signal. I mean it's not gonna hurt anything, but a "T" is all thats needed in that side.
Edit: where did you get the pilot check for $80.00?

It was from a seller on ebay listed new in box and he had it posted for $120, i offered them $80 and payed $11 shipping for it. So $91 total! Here is a picture of it.

 

[sean donato]

It was from a seller on ebay listed new in box and he had it posted for $120, i offered them $80 and payed $11 shipping for it. So $91 total! Here is a picture of it.

Ok, makes sense then I've been looking up the specs for all the valves you've been mentioning and it came up for much more then that.

 

[SemperFiSawguy]

Ok, makes sense then I've been looking up the specs for all the valves you've been mentioning and it came up for much more then that.

Sounds like i got a good deal on it then! Im very excited to see how it performs.

 

[SemperFiSawguy]

Well gents, it looks REALLY cool.
But something aint right. Im not really sure whats going on with it if i got a bad check valve or what, im not entirely sure.

It works extremly well on retract stroke, i mean like, lightning fast.

But its bleeding off pressure on the extend stroke which doesnt make any sense.
Its as if its cracking open simply from rod end port pressure on the return stroke. It will still extend the rod but much slower then normal. So i need to put a gauge on the pilot circuit tomorrow and figure out why its doing that. Either my return pressure on the rod side during the extend stroke is over 25psi or my spring is weak on the check valve.

Have any of you ever plumbed a gauge on your rod end port to measure PSI on that side? I would assume its pretty low since all that side has to do is return oil flowing out of the port unto my filter/tank? I never get more then 10psi on my gauge filter..? Scratching my head about it big time. Heres some pictures.

 

[sean donato]

The filter gauge is just for the filter, has nothing to do with the pressure between the valve and either working port. It's too far down stream for any sort of accurate cylinder reading. So, yes, you need to tee into the line in the cylinder to see what the pressure is in the retract side.

 

[SemperFiSawguy]

The filter gauge is just for the filter, has nothing to do with the pressure between the valve and either working port. It's too far down stream for any sort of accurate cylinder reading. So, yes, you need to tee into the line in the cylinder to see what the pressure is in the retract side.

What is a realistic expectation for rod end pressure during the return stroke? I wouldnt think its too high? If splitez uses 30psi valve i would think its under 30psi no? I figured 25 psi would be perfect. If so im going to try and shim the spring for the cracking pressure and bump it up. If that fails ill have to find a different valve for the same block. The good news is im not out the full cost of this valve which wouldve been $200-350. So thats a plus. And from what ive read hydroforce uses a standard block size for the check valves so i should be able to substitute it with several different part numbers and reuse the block.

 

[sean donato]

Honestly I'm not sure what it is on mine, and not something I ever thought about checking. With the numbers you've come up with and the little research I did while looking up valve specs 30 psi seemed to be the majority of the valves used. Won't really know for sure until you check.

 

[SemperFiSawguy]

Honestly I'm not sure what it is on mine, and not something I ever thought about checking. With the numbers you've come up with and the little research I did while looking up valve specs 30 psi seemed to be the majority of the valves used. Won't really know for sure until you check.

I cant imagine its very high. I am nervous though if it is higher its possible i have internal leakage on either the brand new hydraulic cylinder or the autocycle valve either of which would be upsetting and difficult to trouble shoot. Im not sure how else the pressure could be so high.

 

[sean donato]

Highly doubt the cylinder is leaking internally. But, here's some information on testing
https://www.powermotiontech.com/hydraulics-at-work/article/21885059/how-to-test-a-hydraulic-cylinder

supposedly you can check at end of travel ad well, but you wouldn't know if there's an issue along the tube doing it that way.
Irregardless, it would be a hard sell in my mind for a new cylinder to have bypass.
The auto cycle valve will be a bit trickier to troubleshoot. There are a few youboob videos on it, and some direction in the manual.

 

[rancher2]

SemperFiSawguy. I will jump back in and throw out a few ideas. I have always had a gauge on the pilot line so I could see the pressure. I don't off hand remember what it runs and my wood processing equipment is buried in a shed fifteen miles away. I don't process wood in the winter. I like a lot of gauges on a system so if I am having issues and can see what's going on. I will throw out some ideas. When I have installed a dump valve I always run the dump oil threw { another} filter housing and direct to the tank. So I have at least two filters on a splitter. I don't want back pressure. That's why your running a dump valve. I have four on my processor. I like to use the bigger GPM filter housing Surplus Center part number 9-4543 70 GPM. Your T you have ahead of your filter is necking down some flow it appears in the picture. I wouldn't think you have a cylinder issues or a valve issue causing a back flow. If you had issues with the cylinder bypassing you would be having issues getting your wood split. Put a gauge on that pilot line and see where your out. Think about changing the flow out of the dump valve back to the tank. When I looked at Wolf Ridge splitters on line they don't even run the dump oil threw a filter they go directly back to the tank.

 

[sean donato]

SemperFiSawguy. I will jump back in and throw out a few ideas. I have always had a gauge on the pilot line so I could see the pressure. I don't off hand remember what it runs and my wood processing equipment is buried in a shed fifteen miles away. I don't process wood in the winter. I like a lot of gauges on a system so if I am having issues and can see what's going on. I will throw out some ideas. When I have installed a dump valve I always run the dump oil threw { another} filter housing and direct to the tank. So I have at least two filters on a splitter. I don't want back pressure. That's why your running a dump valve. I have four on my processor. I like to use the bigger GPM filter housing Surplus Center part number 9-4543 70 GPM. Your T you have ahead of your filter is necking down some flow it appears in the picture. I wouldn't think you have a cylinder issues or a valve issue causing a back flow. If you had issues with the cylinder bypassing you would be having issues getting your wood split. Put a gauge on that pilot line and see where your out. Think about changing the flow out of the dump valve back to the tank. When I looked at Wolf Ridge splitters on line they don't even run the dump oil threw a filter they go directly back to the tank.

Good point, I hadn't thought of that. Yes, should have the dump valve going back to the tank in its own return.

 

[SemperFiSawguy]

I played with the check valve today and added some shims, 2 shims helped alot, 3 shims seemed to have been to much and kept the valve closed on retract. With 2 shims though i think im still getting a little bleedoff or crackage through the valve on extend based solely off the cycle time. Its slightly slower then before i added it on the extend and over a full second faster on the retract however, i dont notice ANY tonnage loss and i can still hit relief pressure. Left a messege with a hydroforce engineer today to sub in a different valve thats organically closer to 30psi cracking pressure since 25 seems to be slightly too low. Im going to try and cut one of these washers in half in my lathe demensionally and make a variety of shims to play with the valve i have until i find a sweet spot. Hopefully with the cartridge i alread have.

Based off my pressures though i think i have eliminated any chance of an internal leak on my valves or my cylinder. The pilot pressure seems too be correct.
I cant get a video to upload so heres pictures of my gauges during extend, and retract strokes. So far its still got some leakage and ive gained 1.2 seconds on the extend and lost 1 second on the retract so im about half a second slower then before the dump valve. So somethings going on with the check valve itself either sizing or a bad oring inside it from me taking it in and out so many times.

 

[sean donato]

Right there is a lot of your issue. Too many returns getting bottle necked at the filter.

 

[SemperFiSawguy]

Right there is a lot of your issue. Too many returns getting bottle necked at the filter.

Im going to change that today, that 3/4 T shouldnt be there ill bump that up to 1 inch.

I wouldnt think there is that much restriction there, but 3/4 to 1 inch is a serious jump. Im pretty limited in how i plumb the return as i only have the one 1.5 inch return bung on my tank. Id like to filter the oil post dump valve if i can? You really think an 80gpm 1.5 inch head with 5psi of back pressure is too much? I will change out that T and smooth out some of that return flow today with larger ID fittings and see if that changes anything.

 

[rancher2]

Im going to change that today, that 3/4 T shouldnt be there ill bump that up to 1 inch.

I wouldnt think there is that much restriction there, but 3/4 to 1 inch is a serious jump. Im pretty limited in how i plumb the return as i only have the one 1.5 inch return bung on my tank. Id like to filter the oil post dump valve if i can? You really think an 80gpm 1.5 inch head with 5psi of back pressure is too much? I will change out that T and smooth out some of that return flow today with larger ID fittings and see if that changes anything.

If it was me I would drain the oil down and go back to the tank and put a 1.5" T in there. Bush down to run two 1" hoses one from the control valves and one from the dump valve. If you don't want to buy another filter housing then don't and dump the dump valve oil right back to the tank. I have done it both ways over the years. If splitters are kept inside the oil stays clean in them.

 

[sean donato]

If it was me I would drain the oil down and go back to the tank and put a 1.5" T in there. Bush down to run two 1" hoses one from the control valves and one from the dump valve. If you don't want to buy another filter housing then don't and dump the dump valve oil right back to the tank. I have done it both ways over the years. If splitters are kept inside the oil stays clean in them.

Ditto... filters in hydro systems are an oh pooh thing. Dump to sump would be the best option.

 

[sean donato]

Im going to change that today, that 3/4 T shouldnt be there ill bump that up to 1 inch.

I wouldnt think there is that much restriction there, but 3/4 to 1 inch is a serious jump. Im pretty limited in how i plumb the return as i only have the one 1.5 inch return bung on my tank. Id like to filter the oil post dump valve if i can? You really think an 80gpm 1.5 inch head with 5psi of back pressure is too much? I will change out that T and smooth out some of that return flow today with larger ID fittings and see if that changes anything.

return should be as free flowing as possible. I know, design Constraints and all makes it hard to package some of these things.