OldJarheads Milling Thread...

[barbender]

Jarhead, I believe there is an overall adjustment on the end of the rod where it contacts the microswitch. Then there are individual ones for each function. 

Try this- take a screwdriver and engage the microswitch. That should turn your pump motor on, with no load and no function engaged. See if that sounds like the same sound you are experiencing.

[OlJarhead]

Thanks!  I'll try that as soon as I can get to the mill! (this going back to work thing is cutting into my sawmill maintenance time!) 

[OlJarhead]

Hydraulics Issue - YouTube

ok, pushing with my fingers on the microswitch gives the sound I am talking about.

A little later I move one of the levers a bunch and it starts working so you can hear the difference. This, us the problem I'm having.

[OlJarhead]

Thoughts?  Is it just out of adjustment?  Is the pump coming on before a lever is moved far enough?

Only confusing part is why it doesn't work fine once the valve opens up enough to let fluid flow?  I would think it would whine a second and then get going vs what I have now which can take a minute to get these working.  Like it's not building up pressure?

[barbender]

 Hmm. It's hard for me to tell what's going on in the video. The first part sounds normal, the second one sounds like it is going over relief, like if you lifted the loader arms to the end of the travel and didn't let off the lever for instance.

 Even if the microswitch is out of adjustment and the motor engages prematurely, once you open the valve all the way that function should work immediately.

 I think you have something going on, on the hydraulic side, not your electric motor. Does your mill have a hydraulic guage mounted inside the hydraulic box? It would be useful for troubleshooting.

[OlJarhead]

Interesting.

No gauge inside the box (or lights like Lynn has -- I need to do that I think).

I could do another short that gives a better example where you can hear when it goes over (I hit the up switch and at the end of travel it sounds different) which might help...give me a sec....

[OlJarhead]

Hydraulics issue - YouTube

OK -- here is the full 36 seconds of me pushing on the microswitch and then moving to a lever and running it until the hydraulics starts working.  At one point I think it was the loader and it was bottomed out so it screamed at me a little.

When the pump runs and all is well (or seemingly) you'll here it.  It's aways sounded like that (when it sounds normal to me is at around 3/4 into the video.

[OlJarhead]

Thanks @barbender maybe @MartyParsons @Peter Drouin @Mountain man and others can also chime in?

Could really use some help in this one!

Hydraulics issue - YouTube

[barbender]

It should sound like that at the end of the travel, but your hydraulics should respond right away. Can you shoot a video of say raising your backstop all the way to the end of the travel, in a way we can hear the pump?

[OlJarhead]

I can but will have to do so later after work.

You can hear the pump running 'normally' (at least it sounds normal to me) around the 3/4 mark.  Then I stop and start again, and it stops running right but kicks in again.

Basically that's been the issue:  I hit a lever and it moves very slowly and sounds off (like the pump is running but the fluid aint hardly) then after a while it will start and run fine and as long as I hold the lever it runs fine...when I let go it's back to messing around until it runs right again or I'm done doing whatever it was I needed to do.

So in the video you see me push on the switch and hear the pump, then I move to a level and it sounds the same (more or less), then I hit down but it's at the limit and it yells at me (super short as I let go) then I continue to move the level until finally the pump seems to be running fine, then I stop, it stops and I start again and it's back to screaming at me before it briefly works again.

[OlJarhead]

I did notice it had gotten low on fluid and I had to top it up in November.  I'm wondering if maybe it got air in the lines?  IS there a way to bleed them?

I changed the oil and filter in December but that had no noticeable impact.  Then I did the contact black which also had no impact that I could tell so WM was thinking maybe brushes but if the motor is running and the pump does eventually run, I'm wondering if maybe it's an air lock type issue?

[doc henderson]

I cannot see what is moving or not, and not a WM guy, but I had an issue and it was muck in the valve that was ball valving intermittently.

[OlJarhead]

I was pondering that myself.  But the valves do open and there is some pressure even when it sounds like it does in the beginning (what I call screaming but maybe more of a whine)...I hit the lever and everything is super slow and then eventually it starts to run normally and all is well (though about 10-15% slower now than in July when I first started having an issue with the head needing to come further back on the power bar.

I think I had two issues:  1, contact to the power bar was wearing down and needed to be adjusted/replaced which caused the hydraulics to not work at all and 2, something wrong with the hydraulics developed later which caused the pump to not fully engage until it had been operating for at least 5 to 10 seconds.

[OlJarhead]

I spoke with a local Hydraulics shop, and they suggested it sounds like a stuck ball valve in the manifold.  What he said was that if it was sticking then it wouldn't allow much fluid through at first but once the pressure built up it would be forced open and so the hydraulics would work, let go and the valve resets and you're playing the same game again -- open lever, a little movement, pressure builds, ball valve opens the rest of the way and viola you've got hydraulics again until you let go and the cycle starts again.

The issue I see with this is that there is a half dozen of them so unless each one is sticking (seems unlikely) or unless they all open up one down the manifold, then it's something else.

He also agreed the motor is likely not the problem since it's working and that the issue is either in the pump (failing but strangely if you ask me) or in the manifold and since the microswitch is turning on the pump that isn't the issue.

[doc henderson]

good luck.  sounds like you do good maintenance. but things happen.  dirt in a funnel, or we had a class action against a farm store as their fluid when independently tested, did not meet their state quality.  My buddy Dallas got a check for 1700 bucks.  might try just changing the filter on the hydraulics, maybe clogged but then should not get better.  can you isolate the valve that is responsible?  again I am ignorant to the ways of WM.  might pull the line and do a visual and or spry clean with ether or some oil compatible solvent.  I have an up down solenoid that sticks occasionally, that I have already replaced once.

[OlJarhead]

Well I'll admit, I was late on my oil change and filter change ;) but not by more than 100hrs  :D ;D I should really do it more but in truth, the oil was sure clean looking coming out of the pump when I drained it and the filter was probably fine.  Didn't change anything afterwards so I'm thinking that wasn't the issue.

If the hydraulic manifold the levers are all on has a main ball valve that could be it (you can see it in the video I posted last pretty well) but I think the best course of action is to have them put a flow meter in the system and see what's going on.

[doc henderson]

not that it matters, but I agree with all the above.  My lack of understanding of the WM system, limits my ability to help with diagnosis of your problem.  so in the pics/video, things are more recognizable to those that already are familiar.

[LeeB]

Could well be air in the system. Also somewhat sounds like an intermittent power issue. Somewhere in the forum is a thread about bleeding the hydraulic system but I have no idea where to even start looking. 

[Jack S]

Is there a chance that the coupling between the motor and pump may be slipping? 

[OlJarhead]

No idea on slippage.

Without a good starting point discretion is the better part of valor I often say so I may take it to a shop and have them diagnose it ;)  Let the hydraulics pros do their thing so I can do mine? lol 

I hate to do that but with my limited time (and it looks like I'm working now until late July) I may just have to pack it up and drag it to the local shop so they can diagnose and repair for me.

As long as they don't try to sell me something I don't need.....

[MattM]

After changing the hyd oil did you cycle all the functions to make sure there was no air in the system? Extend and retract each cylinder and hold the lever for a 10 seconds or so after fully extended/ retracted.

Air stuck in the system will cause cylinders to kinda pause for a bit and then start working and seen as how you just changed the oil it's a likely issue with a simple fix.

Hope this helps

Edit: not sure if this applies to our WM mills but I've worked on equipment in the past where what I said to do above would never get the air out and you would have to slightly loosen the fitting at the cylinder to get all the air out.... This usually only happened on machines that had hydraulic cylinders that were the size of our mills...Most likely this isn't the case in these mills as the lines and cylinders are small but I just thought I'd mention it anyways 

[OlJarhead]

Thanks.  No I didn't do that (didn't know I should) however the problem existed before I changed the oil and filter (which is why I decided to).

[fluidpowerpro]

After reading from the beginning, one thing I would check is if the pump inlet has a strainer on it that is clogged. If the pump inlet is restricted, it will cavitate and you will get lots of air in the oil. It does not sound very good either. If you can look into the reservoir filler hole with a flashlight, see if there is air in the oil.

[OlJarhead]

Interesting -- I'm guessing that would be like the ones you see on a garden hose?  Seems strange to have one with a filter but anything is possible I suppose.

[fluidpowerpro]

Unfortunately on the type of power unit Woodmizer uses, if there is a suction strainer, it is located inside of the reservoir. This means to check it, you will likely have to pull the whole power unit and separate the reservoir from the pump/ motor. The pump will be inside of the reservoir and quite often the suction strainer is pushed on to a tube that's on the pump inlet.
 I would recommend asking Woodmizer if there is a strainer before tearing into it. If you do end up removing the reservoir, that would be a good time to clean it out really well.