I am currently housing Wheat harvested by the neighbour who bought my 
combine and grain trailers. He seems pleased with the yield although the 
grain looks a bit thin to me.

The query concerns the hydraulics on the ancient John Deere tractors 
delivering the grain. Both pulsate severely during tipping.

The owner is confident that there is ample oil in the sumps. One appears 
to be connected to a trailer outlet and operated by the linkage quadrant 
and the other via a spool valve.

Is this normal behaviour?

I don't know the models but the older might be a 2012?

regards
-- 
Tim Lamb

Tim Lamb  writes
>I am currently housing Wheat harvested by the neighbour who bought my 
>combine and grain trailers. He seems pleased with the yield although the 
>grain looks a bit thin to me.
>
>The query concerns the hydraulics on the ancient John Deere tractors 
>delivering the grain. Both pulsate severely during tipping.
>
>The owner is confident that there is ample oil in the sumps. One appears to 
>be connected to a trailer outlet and operated by the linkage quadrant and 
>the other via a spool valve.
>
>Is this normal behaviour?
>
>I don't know the models but the older might be a 2012?

Yes, particularly for the smaller machines. The JD pump is precharged
with a low pressure pump in the sump. Unfortunately it has less capacity
than the main pump. This is not a problem with double acting rams or
hydraulic motors because the return is on the low pressure side. Its not
a problem with modest-large single acting rams because it has an
accumulator.

With BIG rams (like tipping rams) the charge pump doesn't keep up
starving the main pump of oil and causing juddering.

Bit of a bugger, this. Never a problem doing anything else though.

-- 
Oz

On Aug 31, 4:17 am, Tim Lamb  wrote:
> I am currently housing Wheat harvested by the neighbour who bought my
> combine and grain trailers. He seems pleased with the yield although the
> grain looks a bit thin to me.
>
> The query concerns the hydraulics on the ancient John Deere tractors
> delivering the grain. Both pulsate severely during tipping.
>
> The owner is confident that there is ample oil in the sumps. One appears
> to be connected to a trailer outlet and operated by the linkage quadrant
> and the other via a spool valve.
>
> Is this normal behaviour?
>
> I don't know the models but the older might be a 2012?
>
> regards
> --
> Tim Lamb

No, Tim, not normal.   Whole hydraulic system of tractor should be
gone through with an inspection of all connections and fittings, fluid
levels.  Simplist solution is to drain whole system after that,
replace hoses or fittings as necessar, replace filters with brand new
ones and re-fill to the proper levels (mark on dipstick)   But, sadly,
the tractor may need a new hydaulic pump.   If there is any sign of
hydraulic oil leaking, the system is compromised.

Burkie

On Aug 31, 4:45 am, Burkie  wrote:
> On Aug 31, 4:17 am, Tim Lamb  wrote:
>
>
>
> > I am currently housing Wheat harvested by the neighbour who bought my
> > combine and grain trailers. He seems pleased with the yield although the
> > grain looks a bit thin to me.
>
> > The query concerns the hydraulics on the ancient John Deere tractors
> > delivering the grain. Both pulsate severely during tipping.
>
> > The owner is confident that there is ample oil in the sumps. One appears
> > to be connected to a trailer outlet and operated by the linkage quadrant
> > and the other via a spool valve.
>
> > Is this normal behaviour?
>
> > I don't know the models but the older might be a 2012?
>
> > regards
> > --
> > Tim Lamb
>
> No, Tim, not normal.   Whole hydraulic system of tractor should be
> gone through with an inspection of all connections and fittings, fluid
> levels.  Simplist solution is to drain whole system after that,
> replace hoses or fittings as necessar, replace filters with brand new
> ones and re-fill to the proper levels (mark on dipstick)   But, sadly,
> the tractor may need a new hydaulic pump.   If there is any sign of
> hydraulic oil leaking, the system is compromised.
>
> Burkie

Goes without saying, but of course, you do that when your tractor is
shut down, NEVER when trying to lift a load and in use.   But then, I
know you're a hell of a lot smarter than that.   (Just a Safety
Reminder)   One shot of hot hydraulic fluid in your eyes would blind
you forever.

In message , Oz 
 writes
>Yes, particularly for the smaller machines. The JD pump is precharged
>with a low pressure pump in the sump. Unfortunately it has less capacity
>than the main pump. This is not a problem with double acting rams or
>hydraulic motors because the return is on the low pressure side. Its not
>a problem with modest-large single acting rams because it has an
>accumulator.
>
>With BIG rams (like tipping rams) the charge pump doesn't keep up
>starving the main pump of oil and causing juddering.
>
>Bit of a bugger, this. Never a problem doing anything else though.

I'll just shut my eyes, then.

Ta.

regards
>

-- 
Tim Lamb

Tim Lamb  writes
>
>I'll just shut my eyes, then.

Yes, or get them to tip more slowly, 
but with plenty of revs so to speak...

-- 
Oz

In message , Oz 
 writes
>Tim Lamb  writes
>>
>>I'll just shut my eyes, then.
>
>Yes, or get them to tip more slowly,
>but with plenty of revs so to speak...
>
 From the looks of the weather and today's thunder showers, there won't 
be much tipping this week!

regards

-- 
Tim Lamb

On Aug 31, 4:47 pm, Tim Lamb  wrote:
> In message , Oz
>  writes>Tim Lamb  writes
>
> >>I'll just shut my eyes, then.
>
> >Yes, or get them to tip more slowly,
> >but with plenty of revs so to speak...
>
>  From the looks of the weather and today's thunder showers, there won't
> be much tipping this week!
>
> regards
>
> --
> Tim Lamb

Tim:   Oz gave some bad advice.   Hydraulic oil, under a standard
pressurized system can kill you, if you are in the wrong place at the
wrong moment.   When you already know a tractor's system isn't working
like it should. you should be extra cautious.   Just giving it more
rev's is not the answer.

Burkie