Rear hydraulic operation

m1ndFacK3RR · Aug 14, 2018

Long time lurker/researcher, and 2nd time poster! This same thread was started in the Cub sub-forum, but there seems to be more action relating to my model (DK45 equivalent) on this one so I'm posting here too.

I picked up an '04 model Cub Cadet 8454 SS w/ 642 loader (426hrs) over the weekend, and so far I've been happy with the purchase. It's been raining since the day we brought it home, so I haven't had a ton of seat time with it yet. To pass the time I've changed the engine oil/filter, fuel filter, and am waiting on the hydraulic filter to change that fluid as well.

My question relates to the rear hydraulic remotes, and the actuating valve to run them. I've got a 3pt wood splitter with it's own dedicated forward/reverse cylinder valve. Hooking the ports up to A/B, and pushing the remote valve lever forward, the splitter works just fine. The remote valve lever will hold in this position until pulled back into the center detent. I've not split any wood yet, it was only a test run, but everything operates fine.

The concern is a disclaimer in the operator manual. It states to not hold the remote valve lever in either direction wherein you're at the cylinder's full stroke. "Doing so will force oil through the relief valve...which will lead to overheated oil." I understand that holding the valve open at a cylinder's full stroke isn't good for it, but in the case where I'm using the splitter's actuating valve this shouldn't apply...correct? Now, if I were to hold the splitter open until the cylinder was at full stroke, and held it, I can see that...but that isn't the case with the way I'm trying to operate it.

I'm probably over thinking it, but don't want to inadvertently cook the hydraulic fluid!

Thanks for any info, and for all of the great posts here that made me feel a little better about the purchase.

:drink:

wagne223 · Aug 14, 2018

m1ndFacK3RR said:
Long time lurker/researcher, and 2nd time poster! This same thread was started in the Cub sub-forum, but there seems to be more action relating to my model (DK45 equivalent) on this one so I'm posting here too.

I picked up an '04 model Cub Cadet 8454 SS w/ 642 loader (426hrs) over the weekend, and so far I've been happy with the purchase. It's been raining since the day we brought it home, so I haven't had a ton of seat time with it yet. To pass the time I've changed the engine oil/filter, fuel filter, and am waiting on the hydraulic filter to change that fluid as well.

My question relates to the rear hydraulic remotes, and the actuating valve to run them. I've got a 3pt wood splitter with it's own dedicated forward/reverse cylinder valve. Hooking the ports up to A/B, and pushing the remote valve lever forward, the splitter works just fine. The remote valve lever will hold in this position until pulled back into the center detent. I've not split any wood yet, it was only a test run, but everything operates fine.

The concern is a disclaimer in the operator manual. It states to not hold the remote valve lever in either direction wherein you're at the cylinder's full stroke. "Doing so will force oil through the relief valve...which will lead to overheated oil." I understand that holding the valve open at a cylinder's full stroke isn't good for it, but in the case where I'm using the splitter's actuating valve this shouldn't apply...correct? Now, if I were to hold the splitter open until the cylinder was at full stroke, and held it, I can see that...but that isn't the case with the way I'm trying to operate it.

I'm probably over thinking it, but don't want to inadvertently cook the hydraulic fluid!

Thanks for any info, and for all of the great posts here that made me feel a little better about the purchase.

:drink:

We will need someone with more hydraulic experience then me to confirm, however.......sounds to me like you got it.

My understanding is , when the splitter has it's own control valve, you leave you tractor lever in the detent position allowing continuous flow. Like you mentioned.

The control valve on the splitter should then bypass fluid back through the return hose when that valve is in the center position. Meaning, no pressure build up on your pump. No overheat concern.

Once you actuate the splitter valve, that is when fluid is directed to the cylinder and pressure builds.

ritcheyvs · Aug 14, 2018

There are two types of valves: open center and closed center. The open center valve allows free hydraulic flow through the valve (to the return) when the valve is centered (two-way valve) or off (one way valve). That type of valve will be fine for your work. But a closed center valve totally stops the flow when centered or off. A closed center valve will cause the pressure relief to open as described in your post. This is not a big deal if brief. But continued flow through the relief is bad in several ways and will likely cause damage.

m1ndFacK3RR · Aug 14, 2018

wagne223 said:
We will need someone with more hydraulic experience then me to confirm, however.......sounds to me like you got it.

Thanks for the post. I hope we're right. :thumbsup:

Kioti Paul · Aug 14, 2018

On my DK45, with the engine running around 1500 RPM (actually anything above idle), I can tell by sound (and "feel") when a cylinder reaches its travel limit (or if I have left the lever in the detent). - IF I'm paying attention! -

With the engine running +/- 1500 RPM, and nothing plugged into the remotes, push (or pull) the lever into detent, and see if you can't tell a definite 'strain to the engine', and a distinct 'whine' in the hydraulics. If you CAN tell the difference, then plug the log splitter into the remote ports, and once again engage the valve's detent and see if the 'whine' returns, or if there is no change to the 'feel' of the tractor. If there is no change with the remote valve in detent, then the log splitter must have an open center valve.

Actually, I can't imagine why a log splitter would have a closed center valve (but then, there are a LOT of things I can't imagine!)

Also, while operating the splitter, if you here a 'whine' after the cylinder reaches its stop (still with the valve opened), but doesn't 'whine' when the valve is released, then I would think it would be safe to assume the valve has an open center. Also, anytime pressure suddenly builds (or releases), if your watching, I think you will see the hoses 'twich' & jump.

I have had my DK45 for about 10 years now; and overall I am quite happy with it. Good luck with your Cub Cadet:drink: