From: Bruce R. Bonar[SMTP:brbonar@wenet.net]
Sent: Tuesday, December 21, 1999 6:48 PM
Subject: Re: [D90] Power Steering Pump
For a lot of good information get a Pullmaster and/or a Bloom catalog. Both companies make an excellent line of hydraulic winches.
(....extraneous material deleted....ed.)
Bruce Bonar----------
From: Jamie Austin[SMTP:jamie.austin@austingroup.co.uk]
Sent: Saturday, June 17, 2000 7:31 AM
Subject: [D90] Milemarker winches
those of you that were asking about hydraulic winches yesterday could check this site i just found in LROI.
Got some good pumps for Tdi engines that fit where the air con compressor goes, wouldn't be too hard to change to fit a V8?
http://www.4x4winches.com/
Jamie
'96 Tdi D110
'92 V8i D90
'85 Tdi D90
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From: ROBERT W. DOWNS[SMTP:RWDowns_WA5CAB@compuserve.com]
Sent: Thursday, December 07, 2000 10:24 PM
Subject: [D90] Subject: Re: Milemarker winch recomendations?
>Bill said:
> I have also heard that if you boost the capacity of the PS pump by
> itself, you start to have seal problems with your steering box because of
> the increased pressure. Don't know if its true but it sounds logical.
That's generally correct. Hydraulic pumps have two ratings of general
interest in intermittent operation - flow rate and operating pressure.
Land Rover power steering pumps operate at 900-950 psi, and the seals in
the power steering boxes are rated accordingly. American pumps typically
run at 1500 psi and will blow the seals in Land Rover steering boxes.
However, winch performance is a function of both pump ratings. Maximum
wireline pull is a function only of pump maximum operating pressure (for a
given winch motor, gearbox and spool). Wireline speed is a function of
those plus pump volume flow rate. So a larger pump, with the pressure
limited to the steering box rating, would improve winch speed up to the
wire line pull limit set by the reduced operating pressure.
Robert Downs
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From: Alan Dobbs[SMTP:gulfcmt@flash.net]
Sent: Thursday, March 02, 2000 1:42 PM
Subject: RE: [D90] new power steering for Milemarker Winch
Clarke Williams asks:
Are you using a higher pressure pump than the stock LR pump?
According to Milemarker, they are looking for pressure around 1500 psig.
The stock pump is 850 psig. The LR Repair Operations Manual I have states
that 1500 psig is "a fault condition" that needs to be resolved before
causing damage to the power steering box seals.
I will be very interested in knowing whether or not you blow the steering
box trying to give the Milemarker enough pressure and volume to function
properly.
Alan Replies:
The simple solution is to add a second relief valve for only the steering
box set at a lower pressure and let the steering pump internal relief be
used for the winch.
It will only generate full pressure when at full wheel lock anyway.
Of course anytime a relief valve is used (internally or externally) heat is
created because the fluid is going from pressure to atmosphere.
I plan on adding a large cooler between the reservoir and pump (low pressure
side) and increasing the reservoir too.
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From: steepcreek@aol.com[SMTP:steepcreek@aol.com]
Sent: Sunday, March 05, 2000 7:14 AM
Subject: Re: [D90] PTO hydraulics/Milemarker fix
I searched for the best possible answer for my Milemarker and found the PTO
option much too expensive to do. For vehicles (Defenders) that do not have
air conditioning you may choose the method that I did. I sourced an
auxiliary power steering pump made by the German ZF company. The complete
kit including pump, aux. belt/pully, mounting bracket, all hoses as well as
all parts needed . The kit costs $320 shipped from the UK to my door and can
be sourced from Allan at Alfred Murray 011446061674. It took only 2hrs to
install. They have a kit for all Milemarker winches for the V8 as well as TDI
engines. The benefit of the kit is you retain 100% steering and have a winch
that will out pull anything. Also if there is a hydraulic problem you can
identify it as either on the steering side or the winch side. For those of
you with air cond you may use the ZF pump for a complete steering pump
conversion but you will need to valve down the pump as it would wreck the
steering box.
Jim
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From: Alan Dobbs[SMTP:gulfcmt@flash.net]
Sent: Thursday, June 15, 2000 6:01 PM
Subject: RE: [D90] winch questions (milemarker)
I have been running the 2 speed 10500 and it does work fine, slow but fine.
I am in the process in installing a separate Saginaw power steering pump on
our 97. We should have a complete Aux pump working by Camp Rover.
One thing about the mile marker besides the speed is when you are on the
trail in a group and if you are the only one who knows how to operate the
controls it makes it miserable for others.
It has happened to us several times including at the Chili Challenge. When I
am on a rock ledge and need to be winched I just cant get out to show others
how to operate. Not like a warn where there is only one lever and it is easy
to operate. Usually I end up yelling out the window how to flip & read the
levers to make the winch operator understand. This compounded along with the
slow speed of pulling makes the group tease you about the winch.
The hydraulic winch works different than the electric because the electric
is limited by its HP to get more pulling power. As for a hydraulic system it
is all relying on pressure to generate the torque.
The factory Land Rover power steering puts out about 700~900 PSI and the GPM
(flow) is around 1 also the factory pump is so small it would fit in the
palm of your hand.
Mile Marker rates the winch at 1500PSI and 3.5 GPM (Gallons per minute) and
even those values are low. Since my profession is hydraulics and machinery.
I know the winch can pull even higher.
I have spoke Mile marker several time about this issue and found out that if
we use the AmSteel rope (presently we are) the pressure can be increased up
to 1800PSI with no harm.
Also if I was to use a remote solenoid valve that is different than the one
mounted on the winch orbit motor, the GPM could be increased to 7 GPM.
Drawback is the heat generated by the flow of oil we would have to have a
reservoir with several gallons to dissipate the BTU's
I presently have a PTO on the transfer case and original was going to mount
a massive hydraulic pump on it.
There are 3 major problems with mounting a pump on the PTO though,
1. The PTO rotates the same as the transmission so if you shift into reverse
while you have the PTO engaged the pump will run backwards and cavatate thus
destroying the pump because it is running dry with no lubrication.
2. RPM of the PTO is dependent on what gear selected, given that "D" is
about 1 to 1 so to run the pump at the preferred operating speed of 1800RPM
a hand throttle is preferred.
3. Since it is mounted on the transfer case you must put the diff in neutral
if you don't want to move. If you want to winch and drive at the same time
it needs to be shifted. Don't know about others but if I was stuck on a rock
ledge the last thing I want to do is try to put the diff in neutral then try
to put it back into low. IMO it is almost impossible to shift the diff thru
hi, N, then to low while stationary.
One good thing with a hydraulic winch that cannot be on a electric, it is
possible to integrated a hand pump like what is on a hydraulic jack. So even
if you are upside down & on fire or whatever you can still pull the vehicle
at its rated winch pull by hand cranking. It will be labor intensive but
easer than a Hi-lift as a come-a-long.
Enough with my rambling...........
Alan Dobbs