Log splitter problem

[reaperman]

Hey guys, I'm having a problem with my log splitter and need some input. First off, its about 4 years old with approx 50 hrs of use. I loaned it out to a couple of friends and when it returned, it came back with a slow cycle time. Normally the cycle time of the splitter is advertised by the manufacturer at approx 13 seconds. Now its more like 22-23 seconds. The splitters specs are, 6.5 hp engine, 11gpm haldex 2-stage, 4" ram.

So far I have changed the hydro fluid, taken out and cleaned the screen filter on the bottom of the tank that the suction line attaches to. I took off all of the hydro lines and blew them out with air. I even took off the cylinder and took it to a hydro shop to test for internal leakage. The cylinder checked out ok. The guy at the shop said the pump was most likely the culprit. So I bought another Haldex 11gpm pump and installed it with the same results. I did take the pump back for a refund. So the pump isnt the culprit either. The only thing I didnt do anything with is the control valve. As I was cleaning out the hydro lines with air. I blew air inside the control, as I moved the lever with air blowing in, I could redirect the air with the lever as fluid would be re-directed. So it seemed to me that the control was working fine.

My only suspicion is where the hydro pump connects with the engine shaft via lovejoy connector. I know it hardly seems possible, but if the pump isnt spinning fast enough that would cause a slower cycle time. I was wondering if it was possible for some slippage to take place on the pump side of the lovejoy connector? I just dont like the key way system on these haldex pumps. Instead of having the key way one continuous slot, there is only a small key slot, less than 1/2 inch long, with a small rounded key to make the connection. I know it hardly seems likely the key is the problem, but I'm out of ideas. One more thing, there isn't a regular hydro filter on the splitter any more. There originally was one on the splitter when it was purchased. But I was contacted by the manufacturer a couple of years ago to take it off due to problems they were having. The splitter is a Northern tool 22 ton. It comes stock with a 5hp honda gc, which I replaced with a 6.5 last year. The engine swap had nothing to do with the cycle time issue.

 

[J_J]

If you think it is the Lovejoy connection, look at the spider and see if it looks OK. Check to see if the Lovejoy engine half is spinning on the shaft, part time. Do you have any idea if the pump is actually putting out 11 GPM's. It is possible that the pimp is stuck in the high pressure, mode, about 1.8 GPM, and 2500 psi. In the high speed mode, the pressure is only about 650 psi, pumping 11 GPM. A hyd gage would indicate the true nature of the beast if you say everything else is working.

The log splitter valve is just going to direct whatever flow there is to the cyl. If it is slow, that means that the pump is pumping low volume, or the cyl is bypassing internally/leaking, making it slow.

Put the gage on the cyl and see if you get the high pressure. Does the relief valve ever go off or squeal, when you hold it full extended? If it does, that tells you that the pressure is there.

 

[mrpoppy58]

Hey guys, I'm having a problem with my log splitter and need some input. First off, its about 4 years old with approx 50 hrs of use. I loaned it out to a couple of friends and when it returned, it came back with a slow cycle time. Normally the cycle time of the splitter is advertised by the manufacturer at approx 13 seconds. Now its more like 22-23 seconds. The splitters specs are, 6.5 hp engine, 11gpm haldex 2-stage, 4" ram.

So far I have changed the hydro fluid, taken out and cleaned the screen filter on the bottom of the tank that the suction line attaches to. I took off all of the hydro lines and blew them out with air. I even took off the cylinder and took it to a hydro shop to test for internal leakage. The cylinder checked out ok. The guy at the shop said the pump was most likely the culprit. So I bought another Haldex 11gpm pump and installed it with the same results. I did take the pump back for a refund. So the pump isnt the culprit either. The only thing I didnt do anything with is the control valve. As I was cleaning out the hydro lines with air. I blew air inside the control, as I moved the lever with air blowing in, I could redirect the air with the lever as fluid would be re-directed. So it seemed to me that the control was working fine.

My only suspicion is where the hydro pump connects with the engine shaft via lovejoy connector. I know it hardly seems possible, but if the pump isnt spinning fast enough that would cause a slower cycle time. I was wondering if it was possible for some slippage to take place on the pump side of the lovejoy connector? I just dont like the key way system on these haldex pumps. Instead of having the key way one continuous slot, there is only a small key slot, less than 1/2 inch long, with a small rounded key to make the connection. I know it hardly seems likely the key is the problem, but I'm out of ideas. One more thing, there isn't a regular hydro filter on the splitter any more. There originally was one on the splitter when it was purchased. But I was contacted by the manufacturer a couple of years ago to take it off due to problems they were having. The splitter is a Northern tool 22 ton. It comes stock with a 5hp honda gc, which I replaced with a 6.5 last year. The engine swap had nothing to do with the cycle time issue.

Dont ever loan Your Tractor, Chainsaw or Woodsplitter. I have BTDT. Poppy

 

[mrmikey]

I think JJ nailed it, probably not shifting from low pressure/high flow to hi pressure/low flow. I think there is an adjustment to change the switchover pressure but saying that there should be no reason to mess with it other than to check for a sticking shuttle.
BTW, the small key you refer to is called a woodruff key, (not being a smarta$$, just fyi )......Mike

 

[AKKAMAAN]

I think JJ nailed it, probably not shifting from low pressure/high flow to hi pressure/low flow. I think there is an adjustment to change the switchover pressure but saying that there should be no reason to mess with it other than to check for a sticking shuttle.
BTW, the small key you refer to is called a woodruff key, (not being a smarta$$, just fyi )......Mike

"nailed it"?? Isn't that when you hit the nail down with one "shot"!!??

I think J_J nailed it in that sentence that he suggested trouble in the right end!!
Check so LoveJoy is connecting the drive shafts.

Since OP had tried a new pump, with no change, status quo, the control valve is the next step. If pump was stuck in low stage mode, cycle time would be close to 50 seconds.

If pump is ok, part of flow must be by passing some where, and the valve is the only option for that.
Either the pressure relief valve is leaking...(stuck open from a debris), or
the spool is not shifted all the way (lever linkage or centering spring assy on the back of spool

The cylinder was already tested. Hopefully the shop knew their job on that one....

 

[reaperman]

"nailed it"?? Isn't that when you hit the nail down with one "shot"!!??

I think J_J nailed it in that sentence that he suggested trouble in the right end!!
Check so LoveJoy is connecting the drive shafts.

Since OP had tried a new pump, with no change, status quo, the control valve is the next step. If pump was stuck in low stage mode, cycle time would be close to 50 seconds.

If pump is ok, part of flow must be by passing some where, and the valve is the only option for that.
Either the pressure relief valve is leaking...(stuck open from a debris), or
the spool is not shifted all the way (lever linkage or centering spring assy on the back of spool

The cylinder was already tested. Hopefully the shop knew their job on that one....

Thanks guys, for the input so far. I do have confidence with the hydro shop, they have a very good rep and do a lot of heavy equipment work. They did replace the seals in the cylinder. They called me up and said there was very minimal leakage at the end of a full stroke, but not enough to cause the trouble I was having. I told them to replace the seals because I know even a minimal leak will only get worst after time.

Back to the control valve. There is an adjustment on the back of the control with a rather large spring. Do I dare mess with that adjustment? The pump does shift from low to high pressure when splitting wood. The whole process is just slower than normal. I have no gauges on the splitter to give me any pressure readings. I could buy a pressure gauge for the splitter, would that help tell me where the problem is? If gauges on my splitter would help isolate the problem, that would be a cheaper option that hauling my splitter to the hydro shop. Thanks

 

[AKKAMAAN]

I could buy a pressure gauge for the splitter, would that help tell me where the problem is? If gauges on my splitter would help isolate the problem, that would be a cheaper option that hauling my splitter to the hydro shop. Thanks

A pressure gauge between the pump and the control valve should always be mounted as a std part of the system, and even a vacuum gauge at the inlet port of the pump is very helpful when trouble shooting these types of problems.

Restriction on suction side, will starve the pump, and will cause low flow and long cycle time.
I read that you cleaned the suction strainer, but also make sure that the suction hose is in proper shape. I have seen the most "reputable" hydraulic shops sell red rubber water hose as suction hose. Even auto radiator hose have been seen. The inner rubber lining can be chemically affected of petroleum based oil, and will collapse from inside.

Make sure you have a proper hydraulic hose with spiral wire to prevent it from collapse under the suction vacuum and from kinking when bent.

 

[RiZak]

Did you check the engine speed? Maybe a little maintenance and some adjustment would help

 

[PHIL850]

Some of the the cheaper splitters I have seen use clear hose on the suction line. this stuff will colapse and starve the pump. Make sure your suction line is not sucking flat.