for D1, late Classics, and likely NAS 90/110 with serpentine belt:
http://3rj.org/Auto/LandRover/PowerSteeringConversion/
http://3rj.org/Auto/LandRover/PowerSteeringConversion/
GM Power Steering Pump conversion
- Thread starter pmatusov
- Start date
Great write up Peter!
Well... if you are sick and tired of mopping up power steering fluid leaks from genuinely-bad ZF setup in the late Range Rover Classics or Discovery Series 1 (with serpentine belt), this article is for you.
One thing that General Motors does well is it designs awesome parts. Engines, transmissions, auxilliaries, you name it. Too bad they couldn't put them all together into an attractive vehicle if their lives depended on it - but at least we the taxpayers allowed GM to stay afloat in bad times so our trove of good parts wouldn't disappear.
One of these parts is GM heavy-duty power steering pump - the descendant
of these ugly-black things that turned the front wheels of anything from a Camaro or a Chevy pickup or a Jeep Wagoneer to school buses. You could throw all sorts of abuse at these things, and they did their job without a hint of classic Ford steering whine. They just work, and don't leak fluid.
But... there's some level of engineering to take you from that knowledge to having one in your truck. The bracket could be hacked together with some spare steel, an angle grinder, and a Harbor Freight Christmas special welder. The pulley could be sourced with the pump, maybe a little too small or too large, and the number of grooves would not necessarily match. The adapters would come from Earl's, locally or from Amazon, be returned and exchanged for proper ones, etc. Eventually, one would get a working setup in a couple of weeks, and chase the gremlins for the months to come.
Enter Nick Markiw.
This is a dude known in Defender circles for his LS3 engine conversion; nothing he does half-assed. After "field-testing" his prototype Disco 1 power steering pump conversion kit for three years and 28 thousand of hard miles, I was confident to pay him for a finalized version I intended to use in the late Range Rover Classic. Since this kit is rather a diversion for his Rover engineering, it took a while to get my hands on the hardware. Finally, after a short trip to his shop in Ramona, California, I had a box full of things that I knew would work together.
The kit includes: pump with pulley, laser-cut front and back mounting plates, bolts to mount the pump on both plates, nuts to attach the pump to the back plate, adapters for the high-pressure pump and steering box ports, a barb-fitting adapter for low pressure steering box port, a foot of hose for low pressure line with hose clamps, a proper-length serpentine belt, and a quart of GM P/S fluid. Lots of stuff in the kit, folks.
Once home, we tore into the Classic's engine bay. If you have one, you know how this all looks.
The fan shroud, fan with clutch, serpentine belt, air filter housing, MAF sensor and hose were removed for easier access to steering gear.
One thing I hate is the ugly mess any involvment with Land Rover steering setup invariably created. I pride myself on having been able to replace the hoses and even the entire steering box without leaking more than three ounces of fluid; this should be a little worse but not much. I figured the ZF pump, reservoir, and all hoses, could be removed as a single assembly.
The pulley is unbolted from the pump, pump - from bracket, and reservoir with the bracket - from the radiator support panel.
Just in case I screwed things up, a drip pan is placed under the front of the truck, and a few absorbent mats thrown on top of it for good measure.
Then, the fittings are unscrewed from the steering box and immediately (not quite hospital operating room immediately, but close) capped.
The pump, reservoir, and hoses, did come out nicely as a single package, with the minimal loss of fluid.
Tools needed to remove the ZF pump, reservoir, and hoses:
- 15-mm socket or 15-mm box wrench to release the belt tension;
- 36-mm fan clutch wrench;
- 10-mm socket for bolts holding the front and rear brackets of the ZF p/s pump to the cast-aluminum bracket housing; the rear bracket that usually comes with the pump requires either a tall (deep) socket or 3-6" extension.
- 13-mm socket for bolts holding the p/s pump bracket to the engine head;
- 13-mm or half-inch wrench that, along with 13-mm socket, works on the radiator support bracket that doubles as reservoir bracket;
- 9/16" and 5/8" flare wrenches for power steering lines at the steering box end;
- 1/4" hex driver for the MAF sensor hose.
Now, it was time to bolt the shiny stuff up.
The back plate is attached to the head using an Allen screw and a spacer; it helps to use the other two long bolts to align the plate with the holes in the head.
Next went the pump with pre-attached front plate. No, it didn't. We just hit a major snag.
The low-pressure port on the pump lands exactly where the left front shock mount is on the EAS-equipped Classics. It would not have been a problem on a Disco, but... what do we do now?
We discussed a few options.
Option 1 involved using inch-and-a-half spacers between the framerail and the shock mount. It wouldn't completely clear the port, so we'd have to bend the tube about half an inch towards the pump body.
Option 2 involved researching the availability of one of myriad versions of the same pump, but with the low pressure port aimed in a different direction. Yes there is such a version, for example, one for 1971 Dodge Charger (then as now, ChryCo gladly used GM hardware whenever they could) - but (a) it used a keyed and threaded shaft, and (b) it was unavailable anywhere in San Diego.
Option 3 involved relocating the front left shock from where it was to a Disco 1 location - through the coil spring. Aside from a slight unease of having front shocks in different locations relatively to the front axle, we needed a Disco 1 shock turret. I just happened to throw a perfectly good pair of these in the trash a couple of months ago, so... we cannibalized one off my old trusty Disco 1 sitting in the garage. The lack of shock turret bolt ring is a minor annoyance; the snag cost us about an hour and a half, since we had to remove the left coil spring, lower spring retainer, insert grade 8.8 8-mm bolts into the holes in the frame spring bracket, and reinstall the spring. Eventually, the shock was relocated, and in went the pump.
Installation of the pump itself, and two short hoses, was so simple and straightforward that it needed no explanations.
Tools needed for installation (omitting the shock relocation process):
- 1/4" Allen driver for the screw holding the rear pump bracket to the head;
- 9/16" or 14mm, and 17-mm open-end and box wrenches to install the GM pump brackets, and attach the pump to the brackets;
- 13-mm or half-inch wrench that, along with 13-mm or half-inch socket, to reinstall the radiator support bracket;
- flare wrenches for power steering lines at the steering box end (forgot the sizes);
- 15-mm socket or 15-mm box wrench to reinstall the serpentine belt;
- 1/4" hex driver for the MAF sensor hose.
Done. Nick Markiw went out of his way to use at least some Land Rover parts - the serpentine belt is a stock part for Discovery Series 2.
The total price of the conversion kit was about a Ben Franklin more than that for a genuine ZF pump and three hoses from Atlantic British.
The lack of frustration with inability to keep the pump from cavitating and fluid from seeping and leaking, and not having to replace fluid-damaged Panhard rod bushings every three years - priceless.
One thing that General Motors does well is it designs awesome parts. Engines, transmissions, auxilliaries, you name it. Too bad they couldn't put them all together into an attractive vehicle if their lives depended on it - but at least we the taxpayers allowed GM to stay afloat in bad times so our trove of good parts wouldn't disappear.
One of these parts is GM heavy-duty power steering pump - the descendant
of these ugly-black things that turned the front wheels of anything from a Camaro or a Chevy pickup or a Jeep Wagoneer to school buses. You could throw all sorts of abuse at these things, and they did their job without a hint of classic Ford steering whine. They just work, and don't leak fluid.
But... there's some level of engineering to take you from that knowledge to having one in your truck. The bracket could be hacked together with some spare steel, an angle grinder, and a Harbor Freight Christmas special welder. The pulley could be sourced with the pump, maybe a little too small or too large, and the number of grooves would not necessarily match. The adapters would come from Earl's, locally or from Amazon, be returned and exchanged for proper ones, etc. Eventually, one would get a working setup in a couple of weeks, and chase the gremlins for the months to come.
Enter Nick Markiw.
This is a dude known in Defender circles for his LS3 engine conversion; nothing he does half-assed. After "field-testing" his prototype Disco 1 power steering pump conversion kit for three years and 28 thousand of hard miles, I was confident to pay him for a finalized version I intended to use in the late Range Rover Classic. Since this kit is rather a diversion for his Rover engineering, it took a while to get my hands on the hardware. Finally, after a short trip to his shop in Ramona, California, I had a box full of things that I knew would work together.
The kit includes: pump with pulley, laser-cut front and back mounting plates, bolts to mount the pump on both plates, nuts to attach the pump to the back plate, adapters for the high-pressure pump and steering box ports, a barb-fitting adapter for low pressure steering box port, a foot of hose for low pressure line with hose clamps, a proper-length serpentine belt, and a quart of GM P/S fluid. Lots of stuff in the kit, folks.
Once home, we tore into the Classic's engine bay. If you have one, you know how this all looks.
The fan shroud, fan with clutch, serpentine belt, air filter housing, MAF sensor and hose were removed for easier access to steering gear.
One thing I hate is the ugly mess any involvment with Land Rover steering setup invariably created. I pride myself on having been able to replace the hoses and even the entire steering box without leaking more than three ounces of fluid; this should be a little worse but not much. I figured the ZF pump, reservoir, and all hoses, could be removed as a single assembly.
The pulley is unbolted from the pump, pump - from bracket, and reservoir with the bracket - from the radiator support panel.
Just in case I screwed things up, a drip pan is placed under the front of the truck, and a few absorbent mats thrown on top of it for good measure.
Then, the fittings are unscrewed from the steering box and immediately (not quite hospital operating room immediately, but close) capped.
The pump, reservoir, and hoses, did come out nicely as a single package, with the minimal loss of fluid.
Tools needed to remove the ZF pump, reservoir, and hoses:
- 15-mm socket or 15-mm box wrench to release the belt tension;
- 36-mm fan clutch wrench;
- 10-mm socket for bolts holding the front and rear brackets of the ZF p/s pump to the cast-aluminum bracket housing; the rear bracket that usually comes with the pump requires either a tall (deep) socket or 3-6" extension.
- 13-mm socket for bolts holding the p/s pump bracket to the engine head;
- 13-mm or half-inch wrench that, along with 13-mm socket, works on the radiator support bracket that doubles as reservoir bracket;
- 9/16" and 5/8" flare wrenches for power steering lines at the steering box end;
- 1/4" hex driver for the MAF sensor hose.
Now, it was time to bolt the shiny stuff up.
The back plate is attached to the head using an Allen screw and a spacer; it helps to use the other two long bolts to align the plate with the holes in the head.
Next went the pump with pre-attached front plate. No, it didn't. We just hit a major snag.
The low-pressure port on the pump lands exactly where the left front shock mount is on the EAS-equipped Classics. It would not have been a problem on a Disco, but... what do we do now?
We discussed a few options.
Option 1 involved using inch-and-a-half spacers between the framerail and the shock mount. It wouldn't completely clear the port, so we'd have to bend the tube about half an inch towards the pump body.
Option 2 involved researching the availability of one of myriad versions of the same pump, but with the low pressure port aimed in a different direction. Yes there is such a version, for example, one for 1971 Dodge Charger (then as now, ChryCo gladly used GM hardware whenever they could) - but (a) it used a keyed and threaded shaft, and (b) it was unavailable anywhere in San Diego.
Option 3 involved relocating the front left shock from where it was to a Disco 1 location - through the coil spring. Aside from a slight unease of having front shocks in different locations relatively to the front axle, we needed a Disco 1 shock turret. I just happened to throw a perfectly good pair of these in the trash a couple of months ago, so... we cannibalized one off my old trusty Disco 1 sitting in the garage. The lack of shock turret bolt ring is a minor annoyance; the snag cost us about an hour and a half, since we had to remove the left coil spring, lower spring retainer, insert grade 8.8 8-mm bolts into the holes in the frame spring bracket, and reinstall the spring. Eventually, the shock was relocated, and in went the pump.
Installation of the pump itself, and two short hoses, was so simple and straightforward that it needed no explanations.
Tools needed for installation (omitting the shock relocation process):
- 1/4" Allen driver for the screw holding the rear pump bracket to the head;
- 9/16" or 14mm, and 17-mm open-end and box wrenches to install the GM pump brackets, and attach the pump to the brackets;
- 13-mm or half-inch wrench that, along with 13-mm or half-inch socket, to reinstall the radiator support bracket;
- flare wrenches for power steering lines at the steering box end (forgot the sizes);
- 15-mm socket or 15-mm box wrench to reinstall the serpentine belt;
- 1/4" hex driver for the MAF sensor hose.
Done. Nick Markiw went out of his way to use at least some Land Rover parts - the serpentine belt is a stock part for Discovery Series 2.
The total price of the conversion kit was about a Ben Franklin more than that for a genuine ZF pump and three hoses from Atlantic British.
The lack of frustration with inability to keep the pump from cavitating and fluid from seeping and leaking, and not having to replace fluid-damaged Panhard rod bushings every three years - priceless.
Awesome, Peter! Thanks for posting that. Gold standard for N-R write-ups.
I just may do this prophylactically while the kits are still available.
RDavisinVA
Technical Excellence Contributor
I am ordering one for our 1994 Disco.
Jrose609
Well-known member
Heh heh.....you said prophylactic-ally
Great write-up, Peter! This the same power steering replacement you did after our last Utah trip a couple years ago?
AdamSanta85
Well-known member
Nice write up! This is the type of content N-R needs.
RDavisinVA
Technical Excellence Contributor
I am not sure if you noticed, but in my trash pile there is a brand new, NEW, genuine, ZF pump. You may also notice no leaks on the hoses, either.
This POS moaned, groaned, and whined like a little bitch from the moment I installed it. No knowledge of fluid dynamics seemed to help to rid it from air or otherwise make not to cavitate.
I have two 95 Classics and two 96 Disco 1s. They are all street-driven, registered, maintained, and ready to head across the continent at a five minutes' notice. I understand that it is more than most people live with, but in my case I have to replace something in the steering system of at least one of them at least twice a year. The lifetime of the gen-u-wine rubber hoses seems to have gone down to 8-14 months or so, before they go mushy and wet.
Not only that. They can also suffer from a catastrophic pump bearing failure - one provided me with a 184-mile tow truck ride in Utah in April of 2013. It happened on a Saturday morning in Salina, Utah, and I have spent two hours on the phone trying to seek a replacement pump anywhere. Between five dealerships (SLC, LV, SD, Glenwood Springs, Scottsdale), not one had one in stock. Ordering from Atlantic British has always been a gamble on time, but getting anything over the weekend is futile. In comparison... I just read the part number on the pump from the posted photo, and found 5 on Amazon and 125 on eBay. It fits a legion of GM and Chrysler products, and is likely to be found in most stores across the U.S.
This tow truck ride pushed me to do the conversion on the D1 (which Nick has suggested for a while prior to that incident). Since May of 2013, I have not added a single drop of power steering fluid, and it is dry as a bone, and covered with fine dust from every Western state short of WA and TX.
Addressing the hose clamps. As you are aware, those are installed on the intake hose for the pump. Both fittings are barb fittings, and the hose doesn't come off even without the clamps. I could have easily tied them up with some lucky charm string, but the clamps came in the bag right at my disposal.
I most certainly did. The pump that blew up on me in Utah was the GM bolt-in replacement. By the way, it turned out even more difficult to source in UT than a Rover pump.
My experience with the GM integral-reservoir pumps is limited to owning a 1984 Chevy Caprice, from 133 to 170kmi (on which everything blew up in two years EXCEPT for power steering components), 1979 Cherokee (in 7 years of abuse with 35" tires, nothing ever happened to P/S components), and currently owned 1968 Wagoneer with 155kmi (or 255?). Not one p/s leak.
As far as fluid capacity, the integral reservoir holds about two ounces more than LR reservoir, so I am not sure where that came from. Also, the pump stands about 1.5" from the head, with a lot of air gap - unlike stock unit that looks like engineers did whatever they could to provide it with the best heat exchange with the cylinder head.
Metal reservoir acts as a heat sink to cool fluid. Plastic ZF bottle does nothing to help cool.
UnfrozenCaveman
Well-known member
Yup, me too...there's one of those in our '94 Disco...you know, I think its the third one.
Sure it's cheap and works...for a little while...but it's blasted noisy - again.
Good thing the rest of the Disco is returning to the minerals from which it came.
Almost the same. I sourced a slightly-oversized pump pulley to under-drive the pump a little bit; also, at that time, we could not find a pulley for a 7-rib belt, so I run a 6-rib belt on my D1.
I would still like to have an oversized pump pulley, or tweak the pump to keep the maximum pressure closer to what the ZF pump provides. Saginaw pump will still provide more flow at any pressure.
Did you replace the reservoir?
Are ZF pump failures common? I've replaced a few on DII's, but my experience on D1's is somewhat limited. In my experience, ZF shit just works.
No, I didn't. I will try to see if there's any dirt in it - but that does not address the issues with the hoses and everything underneath.
ZF shit isn't at all bad. It just is badly under-spec'ed for Land Rovers. 4HP22 is a perfectly good transmission for a Volvo or a E-class or 5-series, but it is a little strained for a D1. IIRC, the same ZF p/s pump was used on 7-series BMW - which is adequate, but not when it has to work twice or three times as hard.
Typically Land Rover steering reservoirs have a screen in the reservoir that will cause cavitation in the pump due to inadequate flow. For example, my brother in law's DII steering pump came apart (only catastrophic failure I've seen) and when I put the new pump I couldn't get it to bleed. Turns out the screen was clogged with metal from the pump. Whenever I do a steering repair I always flush the system before repairing and then replace the reservoir.