Hedge cutter help

[DaveDCB]

It’s about time I get my hedge cutter/flail plumbed up correctly to my 57c , just in the process of replacing the seals on the motor as I let it out to afew people and it came back with blown seals!

So my machine only has duel flow lines and obviously that’s no good on a hedge cutter/flail!
First option is to fit a direct to tank return line , but I don’t really want to go drilling my tank(unless anyone knows of a hidden port on them anywhere!?)

Is there a second option of adding something like a flow diverter (no idea of the name?) between the two hammer lines which would keep the flail spinning thus stopping the seals blowing when there is no input?

I see many flails/cutters which just fit on any machine with no problems, I assume they have a different type of motor fitted? My flail has a Parker 5240D on it for reference.

Any help greatly appreciated

 

[Monkeybusiness]

I’ve just taken delivery of a new flail and had already tee’d a case drain line into the digger’s return line (this is on a 6 tonne Takeuchi). This flail has a piston motor (so there is potential for quite a bit of case drain flow) and the system works perfectly (I was nervous as it had been perfect on a gear pump setup but untested in this guise).

The hoses need tidying/wrapping but you should get the idea -

s**t the bed - my picture isn’t on its side!!! Hoooorayyy!!!!

 

[CPS]

Hi Dave.

Yes you need a valve on the motor to run it down slowly if running on a machine. Had this last week with a customer who bought a flail from an agri dealer... meant to be ready for a digger. They reconded it would work so we tried it but the seals went pretty sharpish.

Your machine will likely have a free return option for a hammer which will work for the flail.

 

[DaveDCB]

Aiden, I think it does have a free return, but the options are all via the computer but they were disabled when the tilty was installed, so now it’s permanent setup for the tilty (I think it was so every time you started the machine you didn’t have to select the correct aux option!) To be honest I was non the wiser as it’s only ever had a tilty on it from brand new so never asked any questions when it was installed.

I got the hammer on it the other week and that works fine but the flail stops dead when you let off the button - creating a large hydraulic puddle!
What value did you add to the flail to make it work??

 

[doobin]

Sounds like it needs a cross line relief mate.

 

[CPS]

What value did you add to the flail to make it work??

None yet.... I left it up to the customer as his supplier was to have done it.

Il look up your motor and try to find the best solution for you.

 

[mart1602]

get a releif valve off a scrap hedgecutter

 

[CPS]

Sounds like it needs a cross line relief mate.

That's the name I couldn't for the life of me think of earlier

 

[doobin]

get a releif valve off a scrap hedgecutter

Or get the correct relief valve from a hydraulic supplier next day...

 

[DaveDCB]

Or get the correct relief valve from a hydraulic supplier next day...

I generally order the wrong part afew times and now have a good stock of various random hydraulic parts..

 

[V8Druid]

as said CLRV is the puppy to stop 'em screaching to a blinding halt ......
however it can also be gotten over with a couple of tees and a check valve between the two lines ..... the check is set/installed so that the P line can not flow to the return in use, but as soon as the pressure is closed at the supply it will continue to rotate, drawing oil (or air) through the check to allow the P line free flow to allow the motor to run down.
Did it on Alex's and worked a treat

could/would 'neat-en' it up with one shorter/longer pipe and some elbows to keep the check parallel with the lines ... .... next time
a LOT cheaper than a 1" CLRV though

 

[V8Druid]

I’ve just taken delivery of a new flail and had already tee’d a case drain line into the digger’s return line (this is on a 6 tonne Takeuchi). This flail has a piston motor (so there is potential for quite a bit of case drain flow) and the system works perfectly (I was nervous as it had been perfect on a gear pump setup but untested in this guise).

The hoses need tidying/wrapping but you should get the idea -

View attachment 9325

s**t the bed - my picture isn’t on its side!!! Hoooorayyy!!!!

only issue with that MB is the possibility of filling the case with oil from the return line ... or have you got a check valve in the drain line to stop any back flow from the T line ?? .... can't see one

 

[Monkeybusiness]

only issue with that MB is the possibility of filling the case with oil from the return line ... or have you got a check valve in the drain line to stop any back flow from the T line ?? .... can't see one

No, nothing on the digger. I’ve just plumbed it as instructed by the suppliers. There might be a check valve in the head itself though as it is built for this application.

 

[DaveDCB]

I woke this morning and literally had a lightbulb moment, pretty much what you have done with that Druid , think I’ll give that a go due to the fact it all works inline without having to get a hose guy out
I assume I need the lowest pressure inline check valve possible?

as said CLRV is the puppy to stop 'em screaching to a blinding halt ......
however it can also be gotten over with a couple of tees and a check valve between the two lines ..... the check is set/installed so that the P line can not flow to the return in use, but as soon as the pressure is closed at the supply it will continue to rotate, drawing oil (or air) through the check to allow the P line free flow to allow the motor to run down.
Did it on Alex's and worked a treat

View attachment 9332

could/would 'neat-en' it up with one shorter/longer pipe and some elbows to keep the check parallel with the lines ... .... next time
a LOT cheaper than a 1" CLRV though

 

[V8Druid]

That's the name I couldn't for the life of me think of earlier

I have days like that too Aiden .... like that slew motor schematic the other night ... but I put it down to senior moments and a very failing memory

 

[V8Druid]

I woke this morning and literally had a lightbulb moment, pretty much what you have done with that Druid , think I’ll give that a go due to the fact it all works inline without having to get a hose guy out
I assume I need the lowest pressure inline check valve possible?

the check valves are normally pretty low rated, pressure wise Dave .... a cone in a seat basically, or a poppet ... spring in 'em just has to keep them seated and the oil pressure in the non return direction does the rest ..
they then let go easily in the opposite direction when needed ...
it just stops the circuit to the motor from becoming sealed/closed off, when the flow from the feed stops abruptly and allows the motor to spin down gently, letting any oil left in the return, re-circulate back into the feed line continuously, 'til the motor has stopped

I used an inch valve as the return was an inch and gave max free flow.

 

[V8Druid]

No, nothing on the digger. I’ve just plumbed it as instructed by the suppliers. There might be a check valve in the head itself though as it is built for this application.

quite possible MB ...... in theory, the flow rate back up the return will suck/syphon oil out of the drain line, rather than back flow .... it's just that stood idle the T line would have the opportunity to drain into the motor case, if not checked

 

[V8Druid]

I generally order the wrong part afew times and now have a good stock of various random hydraulic parts..

knew I'd seen one recently ..... at a price
https://www.ebay.co.uk/itm/Flowfit-...464488?hash=item3a90ae9828:g:Hk0AAOSwYNZazLtv

 

[DaveDCB]

Next saga!

Trying to find a seal for the Parker motor on the cutter, afew companies have come back with nothing, others have said its a Parker/Bomford only part! Quoted £580 for a seal kit from main dealer and £132 from a Parker dealer. I only need a seal with the code
‘CFW A1
BAHDSNSL 1.5
17.47 - 30.16 - 7/5 ‘
I can find seals with the odd size which is correct but the other dimensions are all different! Any ideas??

 

[V8Druid]

Next saga!

Trying to find a seal for the Parker motor on the cutter, afew companies have come back with nothing, others have said its a Parker/Bomford only part! Quoted £580 for a seal kit from main dealer and £132 from a Parker dealer. I only need a seal with the code
‘CFW A1
BAHDSNSL 1.5
17.47 - 30.16 - 7/5 ‘
I can find seals with the odd size which is correct but the other dimensions are all different! Any ideas??

whitehouse products
http://www.whitehouseproductsltd.com/default.aspx?ln=1