Brand new pump locked up?!

I put a brand new pump and valve on the splitter this week. I scrubbed the tank, used new lines, and installed a new filter. I filled the tank with fluid and spun the pump by hand to prime and fill the lines and filter. It felt kind of rough or chattery, but I figured it was a trapped air bubble. Once it was all primed, I fired it up. It ran fine. I cycled the ram a few times and tested the shift point and relief setting. I then turned off the motor to make the adjustments. It would not restart. Turns out the pump was locked up.

We spun the shaft back and forth for a while and it finally freed up. We spun it for a while to make sure and then fired it up. It would barely make 500 psi and adjusting the relief makes no difference. It puts a load on the motor, so the high flow side is pumping. I wonder if it is flowing back through the pump somewhere.

The gauge reads ~500 psi when maxing out cylinder in both directions and the ram is still plenty fast, so I don't think it's a blown piston seal. I don't think a piston seal would just happen to go out at that exact moment anyway.

I'm tempted to open the pump, but I don't know if that will void the warranty, so I have to wait until the company opens on wed to ask them what I need to do. I'm hoping they send a new pump and that takes care of it.

 

Well that stinks!
You might be able to see in just by looking into the in/out ports...I know I could see the gears somewhat that way on the one I just fired up last weekend.

 

Personally I would NOT run it. If it grinds apart all the crap will be in your system.

 

I'm not planning on running it any more than I already have. The whole system will get cleaned and checked over. I could only see a little of the gears through the hole when assembling, so that's not going to be very much help. All I know is something is wrong inside it. I might just tear it down since I have video of it locked up.

 

That does suck. Would you share what brand you got? I'm really close to getting a new pump for my splitter.

 

It was from surplus center. It's a bucher wuxi.

14.1 GPM 2 Stage Hydraulic Pump Wuxi Bucher CBNA-13/1.8 Dirty Hand Tools Log Splitter 107133 | Dirty Hand Tools | Brands | www.surpluscenter.com

 

Good news. I just got off the phone with surplus center. They said they would send out a replacement pump, so I can go ahead and tear the other one apart and find out what happened to make it lock up.

 

I got mine from RuggedMade, but the box says the same brand on it...no issues yet.
18.5 GPM 2 Stage Hydraulic Pump Wuxi Bucher CBNA-16.5/3.0 Dirty Hand Tools Log Splitter 107134 | 2 Stage (Log Splitter) Pumps | Hydraulic Pumps | Hydraulics | www.surpluscenter.com
This would be a good one for The Wood Wolverine since that machine has 10hp on it already.

 

I figured out what happened. The bypass valve blew out of the filter housing and went through the tank and into the pump. The new pump is already here, so I should be all set to put it back together.

I called the filter head mfg (cross) and they said they had never heard of that happening. I have found a few instances of it happening on various firewood forums.
I got the flow/pressure data for the filter and I plan on making an orifice to put in place of the bypass valve to force at least some of the fluid through the filter. I am NOT taking a chance on another valve failing. I will put a pressure gauge on the filter so I can tell what is going on and adjust the orifice size if needed.

 

I got the pressure gauge for the filter housing yesterday. 0-60 psi, so there should be enough gauge that it doesn't max out. I am aiming for a 30 psi max at the very most, like when starting it in winter. One thing I do miss about a gas engine is the ability to idle the motor to warm the fluid. I will have to see how this orifice works out. I'm not sure what kind of pressure drop to expect with this filter/oil combo.

 

I came up with several ideas for making the orifice. I didn't want anything that would come loose. I thought about making an insert that would be retained with an o-ring, but if the o-ring gave out it could fall into the filter. I also considered a pressed in piece, because I have a shop press and a lathe. I finally decided to just measure the hole so I knew what I was working with. Turns out it was almost the perfect size for a 3/8 pipe plug.

I grabbed a pipe plug and one of my taps and it was real close but it worked. I tapped the hole so the plug would screw most of the way in and then put the plug in the lathe. I bored a 5/16" hole in it and trimmed both ends and chamfered the back of the hole (the front of the hole is sharp). I left enough head on it to get a good grip with a socket. The threaded end was trimmed back so it would just go through the aluminum casting, but not block the filter outlet. I used a drop of thread locker and screwed the plug in snug. Then I center punched around it to lock it in even tighter.

I have checked several charts and they all say that a 5/16 hole should be just about right. I can quickly and easily change the orifice if needed.

I need to get everything put back together and then test it. I'm hoping to do that tomorrow. I used a 60 psi gauge because I don't know the exact flow numbers on this filter or the specifics of the fluid. I am hoping to see around 8 psi when the fluid is warm. Cold start pressure might be 20 psi? That's just a guess. Once I know it works, I can make a shouldered press in piece that will be permanent.

 

It's all back together and running. The orifice works great! The temp here is 20-25°, so the fluid wasn't very cold. The filter gauge started out at about 8 lbs and it dropped to zero as the fluid warmed up. I want to do a few really cold starts over the winter and see how high the pressure goes at zero or colder. I can reduce the orifice size, but I don't think I really need to since the filter is flowing better than expected. The oil is getting filtered, so I'm happy.

The cycle time for a full 24" stroke is about 11 seconds and a 17" stroke is 8 seconds. I set the relief at 2,450 psi and the shift pressure is around 400. I'll fine tune it in the wood. I set the detent pressure to around 100-150 psi. I'm excited to pop some rounds!

 

Ok, I just couldn't wait. I pulled the splitter outside and split about 8 rounds of oak and locust. It didn't even feel it. I have some elm in another pile I can split tomorrow. I'm off to bed now. It was a long day cleaning everything up and putting it back together.

 

I have been splitting some wood this evening, and the splitter is running perfectly.

I split about a face cord so far, and it does nat take very long to fill the wheelbarrow....maybe a minute. Then I have to wheel it over and stack it, then another minute of splitting. I need a heard of wheelbarrows and a small army to run them so I can keep splitting.

 

You just need a bigger wheelbarrow.

 

I just wanted to let everyone know why the pump was not making over 500 psi. There was a piece of the bypass valve holding the high/low check ball open and that caused the entire pump to recirculate.

 

Hey guys, long time no see! I just picked up the same pump recently, and was intending to swap the elbow fitting for a straight, but it’s an odd thread I haven’t seen before. Measures 0.975” x 27 TPI, or perhaps M25 x 0.95mm. I see some pumps come with a thread-in straight fitting, which appears to have the same thread (at least visually) but I can’t find this fitting for sale alone anywhere. Any ideas?

… and yes, it’s now “Ashful” over at the hearth. Changed the handle when I ditched the Jotuls for BK Ashfords in 2015.

 

Well hello there...welcome back to FHC!
Somebody has to have them, as I've seen pumps with that fitting not yet attached...I wonder if the surplus place (exact name escapes me right now) would have them?
Edit, Surplus Center, that's the place...I bet if you called their tech line they could hook you up...

 

Yeah, Vevor pumps come to mind, which might just be re-badged Bucher's. Here's one example of what appears to be the exact fitting I need:



The thread appears to be 1-27 UNS, which is not a totally uncommon thread. But for the life of me, I cannot find a 1" hose fitting with that thread. Might be easier to just buy that 16 GPM pump for $100, take the fitting and toss the pump!