Log splitter valve problems, once again

[kevin j]

I am still betting on relief valve or its setting.

Leaking spools or other locations have to pass a lot of flow before bringing the pressure down.

Leakage at high pressure still loads the engine and you should hear it.
If the engine is not working as hard as it did, the flow and pressure are low.

If the bypass setting in the pump was too low, it still should go to full pressure on low speed in the small stage and have full splitting force. It would just unload sooner in the cycle.

Your cylinder leakage rate sounds normal.

Need a gauge.

 

[leon]

:food:

I am still betting on relief valve or its setting.

Leaking spools or other locations have to pass a lot of flow before bringing the pressure down.

Leakage at high pressure still loads the engine and you should hear it.
If the engine is not working as hard as it did, the flow and pressure are low.

If the bypass setting in the pump was too low, it still should go to full pressure on low speed in the small stage and have full splitting force. It would just unload sooner in the cycle.

Your cylinder leakage rate sounds normal.

Need a gauge.

the pump needs to be flow rated to be sure the pump is not bypassing internally kevin, a guage will not indicate that unfortunately

Kevin- I would feel better if he could disconnect the inlet and outlet lines
empty the oil out of the pump and set it on a pail with the inlet side up to check for wear this way; if he pours oil into the inlet of the pump the amount of oil coming out of the outlet-pressure side should be no more than the thickness of a standard no 2. pencil lead if the pumps gears and bronze thrust plates are not worn out in it.

leon

 

[Thunder]

OK, Guys I installed a gauge (see pics). And with the cylinder deadheaded into the wood I am getting about 600 to 650 PSI. Let me know what you think. BTW, I couldn't find a bigger gauge (ROFL)

Thunder

 

[leon]

thunders log splitter

OK, Guys I installed a gauge (see pics). And with the cylinder deadheaded into the wood I am getting about 600 to 650 PSI. Let me know what you think. BTW, I couldn't find a bigger gauge (ROFL)

Thunder

Hello Thunder,

take the pump and valve to a hydraulic repair shop to flow rate themit could be either the pump or the valve.

I know, I know, I know, until thats done we are throwing "Nerf" darts at a "Nerf dart board" with a blindfold in a room with no light and the door closed.

You need a test bench to test the valve and the pump now Thunder.

leon

 

[kevin j]

leon agree 100%. in fact I just wrote quite a lot a bit earlier tonight on that same topic on another post, not replacing parts without understanding what the problem is. pressure isn't a gaurantee of good pump, and low pressure doesn't mean bad pump.
I would just stick a simple hedland flowmeter and relief valve in line and test the pump in 10 minutes, but i assume most people can't and won't do it. Most shops are cautious about running any used equipment on their test bench (possible contamination), and the cost of a shop test might be half the cost of the new pump.
So I am just throwing ideas that ahomeowner can do first before replacing pump or valves. But yes a flow pressure test of the pump would be the ideal choice.

Lacking any equipment, I would still check the relief valve, then adjust it. Also since you got 600 psi,which is suspiciously (but maybe just coincidentally) close to the unloading setting of many pumps, I would pull the pump check valve (the flow out of the low pressure large side of the pump) out and inspect. If the check valve sticks open, the small high pressure side goes back into the low side at the unloader setting. Basically, it makes the unloading valve act exactly like a relief valve.
Your flow test is a good one. It can also be done by holding the inlet hose up, filled with oil, and seeing how fast it leaks out the other side.
Once the pump is off, I'd pull it apart and check before taking to a shop. If it is leaking 11 gpm at 600 psi the wear will be obvious. May save the shop fees, and learn a whole lot aobut pumps. Usually just a few allen or ferry head bolts to take it all apart.

kcj

 

[kevin j]

I have no edit button... what happened?
adding to my post above: another poster, another problem, found a sheared drive key from shaft to gear on the small section, high presure low flow gear, furthest from the engine. This would act just like the stuck check valve I described above. Only pilot signal to operate the unloader would come from the wrong gear set. The large section would pump but unload at some lower than normal system pressure, but act as a relief valve, maybe at several hundred psi instead of unloading totally at 50 psi or so.
not sure I even followed that myself. just check the gear set drive key inside if you open the pump.

kcj

 

[laynes69]

On the inlet side of the pump, there is a cap. When you remove it you should see a slot. Thats your adjustment for your 1st and 2nd stage. I had your exact same problem, except for no pressure at all. I tore down my pump and found the key was sheared on the high side. I went to autozone, and ground and polished a new key and put it back together. What I was having after putting it back together, the engine would stall. I had the adjustment beside the suction side of the pump in too far, at around 600 it would stall. Remove that cap, and turn it out a little and see if that helps. You should be hitting 2nd stage around that psi. I think i'm hitting at 500psi, and I rarely use 2nd unless im in some knotty stuff. If you turn it down and it still won't move to a higher pressure, I would consider tearing it apart just for the peace of mind. You could also have something in the relief valve. My pumps probably 25+ years old and it still kicking strong, even after a key going through it. Don't know how it didn't damage the pump.

 

[Thunder]

Good info guys. Here's the lastest, Removed the pressure relief spring, ball and screw at detent valve (the one with the handle on it). Took it apart and counldn't see anything wrong, rusted or damaged. So I put it back together and still got around 600 psi, so I tried cranking in the relief valve and it made no difference. I cranked it in all the way and still no difference in psi. I put it back to it's original position. Well I guess I'll take a look at the pump and some of the items on the pump you guys mentioned. Also, check out the lovejoy connection.

Thanks, to all

Thunder

 

[Thunder]

Still don't know what's wrong. See pics of pump I took it apart and really can't see anything wrong with it. No scaring of gears/vanes or bores, nothing damaged. Don't know whats next.

 

[leon]

thunders log splitter

Still don't know what's wrong. See pics of pump I took it apart and really can't see anything wrong with it. No scaring of gears/vanes or bores, nothing damaged. Don't know whats next.

========================================================


the fun part:


first;

take the gear set and put it both of them back in the roll bearings one end at a time and wiggle-should be no wiggle period.

second;

take the the gears and end gear housing and reinstall them- then use a good set oif feeler gauges to measure the distance between the gear tooth and the inside of the housing-meaning the flat edge of the gear tooth and the housing-let us know how much distance there is-there should almost no space as the gear pushes oil from the inlet to the outlet

The rule of thumb for gear pumps and motors is this-

a good pump or motor will require the use of a pipe wrench to turn the shaft.


if the pump is bad it will show up here with a gap between the end of the gear tooth and the gear housing = doomed.


judging by the condition of the roll bearings that I saw in you excellent photos I think its time for a new pump-the ends of the hear housings should not have the gouges I see there as the end plates supporting the bearing should be smooth and not gouged like that.

The other item is that the small pumps have highly machined surfaces that seal the oil and do not require bronze wear plates pocket seals and o-rings-you probably noticed it took very little effort to loosen the pump housing.


I would say it is time bid this pump goodby thunder and buy a small vickers vane pump v10-20 with a relief valve plumbed to tank.


vane pumps are very capable to run at high rpm and are more forgiving
as far as trash and are very good at running at cold temeperatures and heat up the oil faster.

I will post a few links for small vane pumps on the forum here.




more close ups of the bearings and end housings will confirm this.

 

[kevin j]

the last pic with the end plate does not look good. leon covered the clearance checks. Was there any end loading on the shaft or coupling?

do you by chance have a known good small hydr motor that could be used as a 'flow meter' by watching speed? Just running the flow through the motor, then to the manual control valve with relief valve, would work as a very crude test. If the motor spins the flow is going across relief or cylinder seals. If the motor stops, it is all pump leakage. Not an accurate test of pump percentage of leakage, but in this case it may be 0% efficient at 600 psi. Way more often it is relief valve issues, but given the pic with end plate wear, that may be the answer.

If you change pumps I would NOT go with single stage pump. Gear or vane doesn't matter, but you are giving up much speed with single stage. The single stage pump is equal to the small section of a two stage. Both are sized by engine hp at maximum psi. The single stage is fixed at that flow regardless of load. The tow stage can add back the larger section and is much faster at lower pressures. More speed. Search back threads for many discussions/arguments!

 

[Thunder]

OK, guys. I'll take a closer look and maybe some measurements. Maybe somemore close ups of the pump also.

Thanks again,

Thunder

 

[leon]

thunders log splitter

the last pic with the end plate does not look good. leon covered the clearance checks. Was there any end loading on the shaft or coupling?

do you by chance have a known good small hydr motor that could be used as a 'flow meter' by watching speed? Just running the flow through the motor, then to the manual control valve with relief valve, would work as a very crude test. If the motor spins the flow is going across relief or cylinder seals. If the motor stops, it is all pump leakage. Not an accurate test of pump percentage of leakage, but in this case it may be 0% efficient at 600 psi. Way more often it is relief valve issues, but given the pic with end plate wear, that may be the answer.

If you change pumps I would NOT go with single stage pump. Gear or vane doesn't matter, but you are giving up much speed with single stage. The single stage pump is equal to the small section of a two stage. Both are sized by engine hp at maximum psi. The single stage is fixed at that flow regardless of load. The tow stage can add back the larger section and is much faster at lower pressures. More speed. Search back threads for many discussions/arguments!

Kevin

the reason I suggested the Vickers vane pump is simply because it will run at the high RPM speeds of the engine much better than the gear pumps and will work very well with a 2000 psi plus relief valve and the fluid flow to the cylinder will be excellent


The vickers vane pumps cartridges are interchangeable and will be able to pump more oil if desired and the plumbing and reservoir can handle the load.


All hydraulic pumps are rated at 1200 RPM at one hundred psi by all manufacturers for initial values.


The quality and power of vickers pumps is something i can verify as they were a main pump for us at the mine where I worked for 22 years.


leon

 

[kevin j]

agree there, the old V and VQ go on forever. also pretty quiet. Easy to change out a cartridge without removing the pump from the line, and the in & out ports can be reoriented very easily.

the 1200 rpm rating on flow is a peculiarly Vickers thing to define the numbers of their vane cartridges. (V20 was 20 gpm at 1200 rpm for instance) I think it came from the early days when most industrial applications ran 1200 rpm motors. Many still do because of noise (both amount of noise and a different frequency that makes it appear much quieter).

no issues with their quality, just that a single stage pump wastes time and doesn't use all of the engine hp anytime it is less than maximum pressure. The two stage allows using the power for higher flows at lower pressure.
Unless there is so much engine hp that more speed is not necessary, I'd never build another single stage system.
That's the only reason for my comment to avoid the vane pumps.

A double section vane pump with external unloading valve would be a nice package as it would allow picking displacements to match the application, not being stuck with the common 1+3 displacement ratios.

kcj

 

[laynes69]

Did you try adjusting the unloading pressure on the pump before removing it? Mine wouldn't kick into high pressure, because the screw was turned in too much. I had to back mine out, and then it was taken care of.

 

[Thunder]

Another Great Speeco customer service story

It's fixed, guess what happened. Carolyn Reyes of Speeco sent me a PM about my problems of low power / pressure on my Huskee 35 Ton log splitter. She sent me manuals of the pump and detent valve. That was very helpful. Sent her the pics of the pump and she forwarded them to the engineering dept. Carolyn said the engineers couldn't see anything wrong right away, but they are sending a new pump and suction hose. Well I thought this is great! The pump and hose arrived about a week later. I finally had time to install the today. I now get 1,500 PSI instead of 600 PSI. The pump costs $ 200 at TSC, the logsplitter is about 8 years old and way past warranty. This comes at great time since we have no extra money right now. I had to take 6 weeks off upaid this due the economy, I live in Michigan so I don't need to say anymore. A great big thanks to Carolyn Reyes and Speeco. Thanks, from my family and myself. Now it's back to splitt'n some wood.

See Ya, Thunder

 

[Mike Van]

Nice people there!