Power steering / engine oil pumps use for waste oil.

Having owned and maitained about 20, mostly GM cars in the 70 - 90 era
I have a lot of old power steering and engine oil pumps. Now I need
to pump waste vegetable oil through a de-watering and particulate (3
micron) filter to a storage tank. I have looked at the price of a
commercial item and am horrified. It needs quite a small flow at
about 50 psi.

I have looked at engine oil pumps and they have a pressure relief
valve that just releases into the sump. I was thinking of putting a
much heavier spring in so it will not operate, but the PS pumps do not
have this problem.

Given that I am willing to modify and sacrifice any old pumps I have,
I rigged up a motor drive to an old PS pump and filled it up with WVO
with the outlet connected to the inlet. It was only running at about
100 rpm but nothing at all happened. It did not prime or circulate.
Thinking I had a broken pump I tried another with the same result.
Both these pumps were working when I took them off old engines and I
wonder why this should be. I assume that looking from the "front" the
pump will rotate clockwise. ( I did reverse the rotation of the
motor, but it did not change anything.) The oil is obviously a bit
thicker than Auto transmission fluid, but I thought it would pump in
the end, if only for a short while. I assume that these pumps are gear
type and if I could get the pulley off, (does it just pull off?) I
would get it apart to see what is happening.


Can any one explain this and suggest the best way to cheaply pump veg.
oil

Thanks for any suggestions George.

George wrote:
> Having owned and maitained about 20, mostly GM cars in the 70 - 90 era
> I have a lot of old power steering and engine oil pumps. Now I need
> to pump waste vegetable oil through a de-watering and particulate (3
> micron) filter to a storage tank. I have looked at the price of a
> commercial item and am horrified. It needs quite a small flow at
> about 50 psi.
>
> I have looked at engine oil pumps and they have a pressure relief
> valve that just releases into the sump. I was thinking of putting a
> much heavier spring in so it will not operate, but the PS pumps do not
> have this problem.

Or you could completely disable the relief valve by putting a solid
piece of bar stock in the space where the spring normally goes...
>
> Given that I am willing to modify and sacrifice any old pumps I have,
> I rigged up a motor drive to an old PS pump and filled it up with WVO
> with the outlet connected to the inlet. It was only running at about
> 100 rpm but nothing at all happened. It did not prime or circulate.
> Thinking I had a broken pump I tried another with the same result.


GM/Saginaw power steering pumps are vane-type pumps, and the vanes are
held in contact with the outer pump housing by centrifugal force. When
operated at low RPM, the vanes never "fling" out and seat against the
housing, so the pump does nothing. At a certain RPM, the vanes will pop
out and the pump will begin pumping. 100 RPM, is barely over 1 turn per
second- WAY too slow.

>
> Can any one explain this and suggest the best way to cheaply pump veg.
> oil
>
> Thanks for any suggestions George.

On May 21, 4:21*pm, Steve > wrote:
> George wrote:
> > Having owned and maitained about 20, mostly GM cars in the 70 - 90 era
> > I have a lot of old power steering and engine oil pumps. *Now I need
> > to pump waste vegetable oil through a de-watering and particulate (3
> > micron) filter to a storage tank. I have looked at the price of a
> > commercial item and am horrified. *It needs quite a small flow at
> > about 50 psi.
>
> > I have looked at engine oil pumps and they have a pressure relief
> > valve that just releases into the sump. I was thinking of putting a
> > much heavier spring in so it will not operate, but the PS pumps do not
> > have this problem.
>
> Or you could completely disable the relief valve by putting a solid
> piece of bar stock in the space where the spring normally goes...
>
>
>
> > Given that I am willing to modify and sacrifice any old pumps I have,
> > I rigged up a motor drive to an old PS pump and filled it up with WVO
> > with the outlet connected to the inlet. *It was only running at about
> > 100 rpm but nothing at all happened. *It did not prime or circulate.
> > Thinking I had a broken pump I tried another with the same result.
>
> GM/Saginaw power steering pumps are vane-type pumps, and the vanes are
> held in contact with the outer pump housing by centrifugal force. When
> operated at low RPM, the vanes never "fling" out and seat against the
> housing, so the pump does nothing. At a certain RPM, the vanes will pop
> out and the pump will begin pumping. 100 RPM, is barely over 1 turn per
> second- WAY too slow.
>
>
>
>
>
> > Can any one explain this and suggest the best way to cheaply pump veg.
> > oil
>
> > Thanks for any suggestions *George.- Hide quoted text -
>
> - Show quoted text -

Thanks Steve, that certainly explains why it does not pump. So I
suppose I should have more like 1000 rpm to make them energise. That
is a pity as I don't need a high flow and I didn't want to use a high
power electric motor, to get it up to that speed I will need at least
1 hp I reckon. I would still like to get the pulley off!

I think I shall go back to the old engine oil one - at least that is
going to pump from very low rpm. I can make a coupling and direct
drive it.

I am still a bit concerned about leakage, though, if this leaks a bit
from anywhere into the sump, it is not a big problem, but if it starts
dripping waste oil all over the place - it's really not so good.

The best way is to lash it up and try it.

Thank again, regards, George.

George > wrote:
>Thanks Steve, that certainly explains why it does not pump. So I
>suppose I should have more like 1000 rpm to make them energise. That
>is a pity as I don't need a high flow and I didn't want to use a high
>power electric motor, to get it up to that speed I will need at least
>1 hp I reckon. I would still like to get the pulley off!

Nahh, you can get it up to high speed without a lot of torque. Get that
pulley off, put a bigger one on, and drive it with the pulley!
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On May 21, 6:45*pm, (Scott Dorsey) wrote:
> George > wrote:
> >Thanks Steve, that certainly explains why it does not pump. So I
> >suppose I should have more like 1000 rpm to make them energise. *That
> >is a pity as I don't need a high flow and I didn't want to use a high
> >power electric motor, to get it up to that speed I will need at least
> >1 hp I reckon. *I would still like to get the pulley off!
>
> Nahh, you can get it up to high speed without a lot of torque. *Get that
> pulley off, put a bigger one on, and drive it with the pulley!
> --scott
> --
> "C'est un Nagra. *C'est suisse, et tres, tres precis."

I may try that as it is already all connected, but it is only 1/4 hp
and it will be driving the oil through a very fine filter, I still
think it will prove to be too much of a load. I chose the smallest
pulley on the motor I could find because I didn't want a big flow. I
shall let you know if it works after I try it tomorrow, it's
dinnertime here in UK now.

Do you think there are any seals which will not like veggie oil?

Thanks George. Diesel up to six pounds a gallon now! That is about
12 US$.

On May 21, 11:10*am, George > wrote:
> On May 21, 6:45*pm, (Scott Dorsey) wrote:
>
> > George > wrote:
> > >Thanks Steve, that certainly explains why it does not pump. So I
> > >suppose I should have more like 1000 rpm to make them energise. *That
> > >is a pity as I don't need a high flow and I didn't want to use a high
> > >power electric motor, to get it up to that speed I will need at least
> > >1 hp I reckon. *I would still like to get the pulley off!
>
> > Nahh, you can get it up to high speed without a lot of torque. *Get that
> > pulley off, put a bigger one on, and drive it with the pulley!
> > --scott
> > --
> > "C'est un Nagra. *C'est suisse, et tres, tres precis."
>
> I may try that as it is already all connected, but it is only 1/4 hp
> and it will be driving the oil through a very fine filter, *I still
> think it will prove to be too much of a load. I chose the smallest
> pulley on the motor I could find because I didn't want a big flow. I
> shall let you know if it works after I try it tomorrow, it's
> dinnertime here in UK now.
>
> Do you think there are any seals which will not like veggie oil?
>
> Thanks George. * *Diesel up to six pounds a gallon now! *That is about
> 12 US$.

that's a lot of money!

> wrote in message
...
> Diesel up to six pounds a gallon now! That is about 12 US$.

that's a lot of money!

===

Yes the cost of petrol and diesel (diesel especially) is going up on a day
by day basis. The highest I've seen near me is £1.30/litre for diesel which
is £5.91/UK gallon or £4.72/US gallon. Using today's exchange rate of
£1=$1.88, that's 4.72*1.88 = $8.88. Not quite as much as the OP said - he
forgot to convert UK to US gallons and assumed £1=$2 exchange rate - but
it's still a lot of money. Make us jealous in the UK - how much are gas and
diesel in the US, typically, these days?

On May 22, 1:03*am, wrote:
> On May 21, 11:10*am, George > wrote:
>
>
>
>
>
> > On May 21, 6:45*pm, (Scott Dorsey) wrote:
>
> > > George > wrote:
> > > >Thanks Steve, that certainly explains why it does not pump. So I
> > > >suppose I should have more like 1000 rpm to make them energise. *That
> > > >is a pity as I don't need a high flow and I didn't want to use a high
> > > >power electric motor, to get it up to that speed I will need at least
> > > >1 hp I reckon. *I would still like to get the pulley off!
>
> > > Nahh, you can get it up to high speed without a lot of torque. *Get that
> > > pulley off, put a bigger one on, and drive it with the pulley!
> > > --scott
> > > --
> > > "C'est un Nagra. *C'est suisse, et tres, tres precis."
>
> > I may try that as it is already all connected, but it is only 1/4 hp
> > and it will be driving the oil through a very fine filter, *I still
> > think it will prove to be too much of a load. I chose the smallest
> > pulley on the motor I could find because I didn't want a big flow. I
> > shall let you know if it works after I try it tomorrow, it's
> > dinnertime here in UK now.
>
> > Do you think there are any seals which will not like veggie oil?
>
> > Thanks George. * *Diesel up to six pounds a gallon now! *That is about
> > 12 US$.
>
> that's a lot of money!- Hide quoted text -
>
> - Show quoted text -

Actually that is Imperial Gallons which I think are a bit bigger than
US ones.

A busy day today but I did change the pulley (and the motor, for a
slightly bigger and faster one and away it went, - oil rapidly
circulating round the transparent pipe from exit to input. So far so
good, but a couple of things do occur to me. What about the
reservoir. There may not be any suction in the input pipe. and so
how do I maintain the volume in the reservoir. It is OK on a closed
circuit like I have now, but how about pumping from a tank, through a
filter to another tank. I am not sure if the cap is airtight, in fact
it cannot be to allow for temperature volume changes.

I suppose I could permanently close the cap and then, if anything gets
pumped out there will have to be a suction to drag some more in. I
may go back to an engine oil pump just to see if it does leak at all,
because if it does not I feel this would be the preferred way to do
it.

I have been making a mounting plate for the 3 micron filter, as
whatever pump I use this will be needed. I may get round to this
tomorrow.

Regards George.

"George" > wrote in message
news:bcb4b7d4-215e-4d99-. That
> >is a pity as I don't need a high flow and I didn't want to use a high
> >power electric motor, to get it up to that speed I will need at least
> >1 hp I reckon. I would still like to get the pulley off!

Sometimes it is better to filter using simple hydrostatic head if you have
the time to wait...

If you want to reduce the flow on your pump, install a partial bypass line,
from high pressure side to intake...Put a metering valve in that line and
you
can let the pump reach its operational speed, but you can still throttle the
fluid
such that you dont put too much pressure on the filter.

On May 25, 12:43*pm, "HLS" > wrote:
> "George" > wrote in message
>
> news:bcb4b7d4-215e-4d99-. That
>
> > >is a pity as I don't need a high flow and I didn't want to use a high
> > >power electric motor, to get it up to that speed I will need at least
> > >1 hp I reckon. I would still like to get the pulley off!
>
> Sometimes it is better to filter using simple hydrostatic head if you have
> the time to wait...
>
> If you want to reduce the flow on your pump, install a partial bypass line,
> from high pressure side to intake...Put a metering valve in that line and
> you
> can let the pump reach its operational speed, but you can still throttle the
> fluid
> such that you dont put too much pressure on the filter.

Goood idea!

Today I got my first 5 gallons or so filtered, but I was not very
happy with the process. Even though I found a smaller motor pulley,
it was going too fast and sucking air in via the filler cap. The
pressure across the filter was too high as well
and got up to about 60 psi. I think if I closed off the filler cap,
got an even smaller belt pulley to make it run even slower AND put in
your bypass, I will be in business.

Like I said earlier I do have an engine oil pump which is very small
and neat but has an awkward drive rod and no seals. I have machined
a groove in the drive shaft and inserted an O ring, which may do the
trick there and blocked up the pressure relief escape. I just have to
turn it in a satisfactory manner. With a slower motor and a bypass I
think this will be OK. Only one input and one output.

I shall put sealer on the faces of the two halves of the body as there
is no gasket and give it a whirl. What I have now is more or less
working, but all the bubbles being drawn in caused it to expand
rapidly when the motor stopped and it poured oil out of the filler cap
which does not seal at all. It made an awful mess.

Ideally I want a lower pressure, slower flow which I can leave on for
hours at a time as I am pumping from one 300 gallon tank to another,
i.e. from a pre-filtered and settled tank to a 3 micron filtered and
de-watered tank, prior to putting it in my truck.

Thanks for your comments, regards George.