Low Pressure return on seed drill fan

[jonnieboy]

I asked this on my Pimp my drill thread but it maybe got missed

Seed Fan is hydraulic driven with a 3/4 return to tractor back end not back through the spool valve
I'm putting another drive on for the liquid Fert system, would it be possible to T into the 3/4 return and send both motor returns through the same hose ? I guess as long as the return pressure isn't to high it should be ok ?? anyone done this ?

 

[Pheasant Surprise]

It should be fine. However if you wanted to be absolutely certain, you could put a 3/4" check valve, with very low cracking pressure, (less than 0.5 bar) in the return / drain line from each motor going into the T.

 

[Andrew K]

I would check your tractor has enough in reserve to drive both motors plus a bit spare first?

 

[Andrew]

Most fan motors can cope with quite a bit of pressure in the return line. However, they need a low pressure case drain. Most manufacturers tee the case drain into the free flow return with a restrictor. It may be that the motors will run fine, but on startup there will be pressure spikes into the case drain, which will cause failure.
Depending on what motors you may be able to run them in series, with the return into a spool and the case drains t'd together into the free flow return.

Can you post the make and size of each motor? Also the tractor model / hydraulic output per spool?

 

[jonnieboy]

Will check sizes tomorrow neither are big motors though
I am intending powering then through 2 spools as the liquid fert one will be pressure/speed dependant so I will set the pressure with spool valve flow I think the last time I used it there was only 8-10% on flow to get correct pressure
Just trying to save piping another line into the tractor

 

[jh.]

Friend of mine with electric spools returned a hydraulic motor through spool with no problems , for years . He now has pressure free return but only because it came as standard on his later tractor.

I always thought they must be pressure free returned but seemingly with electric spools below 50% flow they are fine .

Check with your dealer tho

 

[jh.]

How did you get on with this.

As it happens I have just fitted a 3/4 return to my tractor on Friday. Despite having electric spools , I just think it must run cooler going straight to tank return plus have the different fittings on the hose so won't get them around the wrong way when yoking up . This is where I teed into on a 74 Massey , for a front fert tank I'm fitting

 

[jonnieboy]

Is there not already a free flow return on the 74 ? I’m sure we found one on the old 64 we had there’s one or 2 blank ends on the back end ?
I had to get a new motor last week and spoke to the tech guy at suppliers and he was happy with both motors returning through one 3/4 hose
There’s more pressure created running returns through the spool valve . There is a gauge on the return line so it’s a case of making sure return pressure doesn’t go above 1.5 bar

 

[jh.]

Is there not already a free flow return on the 74 ? I’m sure we found one on the old 64 we had there’s one or 2 blank ends on the back end ?
I had to get a new motor last week and spoke to the tech guy at suppliers and he was happy with both motors returning through one 3/4 hose
There’s more pressure created running returns through the spool valve . There is a gauge on the return line so it’s a case of making sure return pressure doesn’t go above 1.5 bar

Yeah new one on left goes to front , the right with red paint dot is going to rear for drill