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Well I completed this conversion as well thanks to you guys sharing all the info. On the M137 its a bit different. There was no need for the PS line modification. there are 2 bolts holding it underneath, once those are out there is enough give to connect to the ps only pump, I just had to make sure there wasn't stress on the line and it was underneath the exhaust heat shield which was easy enough. I actually had a hydraulic shop fab up a 5" extension hose that I didn't end up using at the end. After all the maintanence I ended up doing during the process, the performance improvement is pretty great.
Not gonna lie about it, with all the things I learned during this process about the ABC, it would have been a better idea to repair the problem probably, but I'm not complaining about the strutmaster conversion. All I'm saying is there is a ton of knowledge thats shared here to fix the problem but the expense factor may come in....to each their own I guess...
Well I completed this conversion as well thanks to you guys sharing all the info. On the M137 its a bit different. There was no need for the PS line modification. there are 2 bolts holding it underneath, once those are out there is enough give to connect to the ps only pump, I just had to make sure there wasn't stress on the line and it was underneath the exhaust heat shield which was easy enough. I actually had a hydraulic shop fab up a 5" extension hose that I didn't end up using at the end. After all the maintanence I ended up doing during the process, the performance improvement is pretty great.
Not gonna lie about it, with all the things I learned during this process about the ABC, it would have been a better idea to repair the problem probably, but I'm not complaining about the strutmaster conversion. All I'm saying is there is a ton of knowledge thats shared here to fix the problem but the expense factor may come in....to each their own I guess...
looks great ! So you are saying on the m137 v12 that a v8 ps pump is a direct swap for the v12 tandem pump and no pulleys or hoses need to be fabricated ? Or does some of That work still need doing ?
I used TenZero's measurements for the spacers, the 3rd spacer doesn't need to be split in half so I got all of them the same length. The hose didn't need any fabrication and the pulley that comes on the v8 pump is same size so I just used the 6 rib belt as he did. The high pressure line for the ABC is one long piece that goes around the transmission so I had to cut the end off that to fit the new pump. It didn't matter since ABC lines have no fluid/pressure. I also used the same reservoir, the ABC and the PS sides are separate so the big ABC part is just empty. I had to trim a bit of the rubber hoses that go from pump to reservoir because it doesn't line up exactly but the angles worked out.
Not sure if anyone is already talking about this but, for those of us who have converted from ABC to coilovers and have kept the small hydraulic radiator in the front, could we be repurposing it to add additional cooling to other sections...i.e. the intercoolers, etc. Just thinking out loud...thoughts anyone?
I’m needing some info on the steps I need to take.. my dampener hose busted will the recirc work or how can I get part to convert to v8 non abc power steering pump
Originally Posted by TenZero
Backstory: I bought my 2004 S600 with 78k miles and failed ABC. Had it towed to my house, (had to use a special race car trailer because it sat too low for the flatbed wrecker. I paid $2700 for the car, which was a "can't lose" price; the seller was just done spending money on it, and the $3k estimate for fixing the ABC again just pushed him over the edge. Anyway, I got a nice low mileage car (not a creampuff) for silly money. My intention was to delete ABC and go to coilovers from the get go. After a less than pleasant experience with Strutmasters, I ended up with a set of Yellowspeeds in the car, which I'm very happy with. Since my ABC system was ruptured, I have simply been running the ABC side of the pump dry, which I've heard may or may not work.
I've been enjoying the car for the last 6k miles, until recently, when the power steering began complaining. It became hard to turn at low speeds, and making uncomfortable groaning noises. Info on this forum indicated that the ABC pumps do not last long running dry, but a popular conversion for V8 cars was to swap power steering pumps from an air ride car. Unfortunately for me, it seems no one has done this on a V12 yet. User Cowboyt is running coilovers on his V12 with a fluid recirc to a regular ABC pump.
I like the idea of running the V8 PS only pump on my V12 car, but there are some obstacles, which as far as I know, nobody has solved yet. So I got busy trying. First, I bought a used PS only pump off of an S500, with the idea getting both pumps in my hands to compare them and see if it is worth doing. Comparing pictures was very promising! Then, I removed the tandem pump from my V12, (and you know what a pain that is) and got them on the bench together. Well, there are some obstacles!
1) The pulleys don't match. V12s have a 7 rib belt, V8s have a 6 rib belt.
1.5) Pulleys are not interchangeable
2) The mounting holes are the same pattern, but there is a lot of space to make up just to get the V8 pump to match the V12 belt line.
3) The rear mount is different.
4) The power steering line output is in a different position. Big problem!
5) The V8 pump mounted fluid reservoir interferes with the V12 coilpack.
Photo shows my V12 tandem pump (top) and a V8 PS pump (bottom) with the mounting tabs roughly aligned. Offset is significant.
So, my ideas were that I would need to custom fab something(s) to make this work. But What?
1) Spacers/mounts/bracket to match M275 beltline (not too bad, if you get the measurements right the first time)
2) Custom 7 rib pulley to match beltline (LOTS of machine time =$$)
3) Custom PS output line (Again, not too bad)
4) Rerout reservoir supply to OEM remote tank. (Easy)
5) Custom PS fluid reservoir
6) Convert V12 to 6 rib belt to match PS pump with off the shelf Ford part (Easy!)
If none of this works, I will buy a reman ABC pump, and fab a fluid recirc system like Cowboys
looks great ! So you are saying on the m137 v12 that a v8 ps pump is a direct swap for the v12 tandem pump and no pulleys or hoses need to be fabricated ? Or does some of That work still need doing ?
Sorry if I missed it but, which coilover or strut kit did you go with and what has been your experience?
My take on this process, taking what I learned from the OP.
First of all, let me preface this post with saying there is a special thanks to people that post technical & creative solutions for others to find & benefit from.
Modified OEM V12 hardline with a soft line extension mounted onto an M275 engine, with an S500 power steering pump. Cut off the 125° male end of the OEM hardline Hairline should measure 19.125” from the outer edge of the fixed female fitting to the back side of the -6 JIC Male fitting that is to be brazed onto the hardline. Close up look at the OEM female fitting on the OEM hardline Centerline of the 90° fitting in the patch hose Close up of the -6 JIC MALE fitting that needs to be brazed onto the hardline, where the original 125° elbow & fitting were. Bump tube adapter to -6 JIC fitting This fitting threads into the power steering pump & the patch hose thread onto the adapter. Overall view of the patch hose
If you ever want to convert your V12 ABC pump to a standard power steering pump, you will need to machine 4x spacers.
Spacer material.
aluminum
.750” outer diameter
9mm inner diameter
2x @ 1.375” long
2x @ .600” long
You will need the following hardware to mount the new pump & spacers:
2x M8x1.25x70mm
1x M8x1.25x60mm
3x M8 washers
Spacer location:
1x 1.375” spaced on the left side (when facing the front of the engine) affix this spaced with a 70mm long M8x1.25 bolt & washer.
2x .600” spacers used on the upper right side (they sandwich the original triangular steel bracket that was used for the V12 pump) affix the steel bracket with the original E10 Torx hardware & put 1x .600” spacer on each side. Then affix the pump & spacers by using a 70mm long M8x1.25 bolt & washer (spacers are actually different sizes, but it’s less than 0.003”, so it’s not worth resizing them)
1x 1.375” spacer gets installed from the rear side of the pump through the pump bracket via a 60mm long M8x1.25 long bolt & washer.
This will align the new power steering pump with the remaining V12 pulleys.
The V12 pulleys are 7x rib & the S500 power steering pump is a 6x rib pulley.
You will need to run a new 6x rib serpentine belt for your engine (this is not a big deal, as the dual pump was the biggest mechanical drag on the accessory system.
The reason for the redundant guide, it it’s a copy of a text message conversation
Power steering hardline should be cut to the length where the distance from the outer tip of original female fitting edge & the backside of the new -6 JIC fitting that needs to be brazed.
You will be cutting the end off with the 125°floating male end
You will be brazing the new fixed -6 JIC fitting on & position it @ 63°
The patch hose will be 6.75” in length from the outer flat edge of the 0° floating -6 JIC female fitting to the center line of the 90° floating -6 JIC female fitting
You will need a fixed male 0° bump tube adapter that will thread into the V8 power steering pump sourced from an AirMatic S500 ( part # A 00 546 675 01)
Disclaimer warning:
Removing the original tandem pump for the ABC system required me to drop the front subframe.
This swap isn’t the easiest, but I’ve done all the math for you, in case you are cautious about tackling custom work.
I just want to say thanks for documenting this job. It really helped me a lot when I did this conversion on my 2001 Mercedes S600.
I already had a lathe so the bushings were easy thanks to you documenting and publishing the dimensions here. The only problem I ran into is the replacement power steering pump did not come
with the A-shaped bracket and I had to fabricate that piece myself. That was the hardest part of the whole job.
There's just no good or easy way at all to hold things into place to measure for making a bracket. It was a real..well, you know what I mean!!
To anyone getting ready to do this job. If you don't receive a pump with the special bracket TenZero talks about, don't even start, just find one with the bracket.
It's a real B...ch trying to make one like I did.
The Dayco belt is spot-on. Perfect fit. I was able to use the original high pressure power steering line simply by disconnecting some brackets under the transmission and re-routing it slightly. It took a little time, but it was just long enough to make it.
Be sure to bleed the power steering system by turning the steering wheel lock-to-lock 80+ times with the wheels off the ground and the power OFF before
starting the car for the first time checking the fluid every 10 times or so and topping off as needed. This is called for in the Mercedes WIS documentation. Air will damage or destroy the pump. Take the time to bleed it correctly! Good luck to
anyone else about the do this job.
Last edited by I drive a Ford; 04-12-2022 at 12:00 PM.
I just want to say thanks for documenting this job. It really helped me a lot when I did this conversion on my 2001 Mercedes S600.
I already had a lathe so the bushings were easy thanks to you documenting and publishing the dimensions here. The only problem I ran into is the replacement power steering pump did not come
with the A-shaped bracket and I had to fabricate that piece myself. That was the hardest part of the whole job.
There's just no good or easy way at all to hold things into place to measure for making a bracket. It was a real..well, you know what I mean!!
To anyone getting ready to do this job. If you don't receive a pump with the special bracket TenZero talks about, don't even start, just find one with the bracket.
It's a real B...ch trying to make one like I did.
The Dayco belt is spot-on. Perfect fit. I was able to use the original high pressure power steering line simply by disconnecting some brackets under the transmission and re-routing it slightly. It took a little time, but it was just long enough to make it.
Be sure to bleed the power steering system by turning the steering wheel lock-to-lock 80+ times with the wheels off the ground and the power OFF before
starting the car for the first time checking the fluid every 10 times or so and topping off as needed. This is called for in the Mercedes WIS documentation. Air will damage or destroy the pump. Take the time to bleed it correctly! Good luck to
anyone else about the do this job.
I just used the remaining bracket from the tandem pump setup.
It had ABC (Active Body Control).
The pressure line blew which runs "underneath" the engine and would have required removing the engine to repair.
My Tandem pump burned up but it did not have a bracket. I still have the old pump but didn't take pictures of it.
It just has what I would call, "ears" that protrude from the housing with holes in the ends that you put the bolts through to attach it to the
engine. Sure would have been easier if it had a removable bracket I could have re-used on the new pump.
The Strutmaster's coilover conversion kit I purchased was excellent. Their instructions were excellent.
If there was no way to do a coilover conversion, this car was essentially scrap at the instant that pressure line blew underneath the engine.
Couldn't drive it, move it, nothing. It was flat on the ground. Hell of a time bomb that ABC system is!
Mercedes offered rubber blocks that went between the suspension and the chassis to allow you to move and even drive the car.
A friend bought rubber wheel chocks, tie-wraps and a hacksaw from a (very luckily convenient) Harbor Freight store and MacGyvered a workable substitute when an Airmatic strut failed on the road.
I used his rig to get an S500 home when I bought it with a failed rear strut.
Backstory: I bought my 2004 S600 with 78k miles and failed ABC. Had it towed to my house, (had to use a special race car trailer because it sat too low for the flatbed wrecker. I paid $2700 for the car, which was a "can't lose" price; the seller was just done spending money on it, and the $3k estimate for fixing the ABC again just pushed him over the edge. Anyway, I got a nice low mileage car (not a creampuff) for silly money. My intention was to delete ABC and go to coilovers from the get go. After a less than pleasant experience with Strutmasters, I ended up with a set of Yellowspeeds in the car, which I'm very happy with. Since my ABC system was ruptured, I have simply been running the ABC side of the pump dry, which I've heard may or may not work.
I've been enjoying the car for the last 6k miles, until recently, when the power steering began complaining. It became hard to turn at low speeds, and making uncomfortable groaning noises. Info on this forum indicated that the ABC pumps do not last long running dry, but a popular conversion for V8 cars was to swap power steering pumps from an air ride car. Unfortunately for me, it seems no one has done this on a V12 yet. User Cowboyt is running coilovers on his V12 with a fluid recirc to a regular ABC pump.
I like the idea of running the V8 PS only pump on my V12 car, but there are some obstacles, which as far as I know, nobody has solved yet. So I got busy trying. First, I bought a used PS only pump off of an S500, with the idea getting both pumps in my hands to compare them and see if it is worth doing. Comparing pictures was very promising! Then, I removed the tandem pump from my V12, (and you know what a pain that is) and got them on the bench together. Well, there are some obstacles!
1) The pulleys don't match. V12s have a 7 rib belt, V8s have a 6 rib belt.
1.5) Pulleys are not interchangeable
2) The mounting holes are the same pattern, but there is a lot of space to make up just to get the V8 pump to match the V12 belt line.
3) The rear mount is different.
4) The power steering line output is in a different position. Big problem!
5) The V8 pump mounted fluid reservoir interferes with the V12 coilpack.
Photo shows my V12 tandem pump (top) and a V8 PS pump (bottom) with the mounting tabs roughly aligned. Offset is significant.
So, my ideas were that I would need to custom fab something(s) to make this work. But What?
1) Spacers/mounts/bracket to match M275 beltline (not too bad, if you get the measurements right the first time)
2) Custom 7 rib pulley to match beltline (LOTS of machine time =$$)
3) Custom PS output line (Again, not too bad)
4) Rerout reservoir supply to OEM remote tank. (Easy)
5) Custom PS fluid reservoir
6) Convert V12 to 6 rib belt to match PS pump with off the shelf Ford part (Easy!)
If none of this works, I will buy a reman ABC pump, and fab a fluid recirc system like Cowboys
Project in progress, updates as they occur!
We didn’t need to relocate the reservoir. All in cost me $1300 CND and everything runs as it should. Any good mechanic can do this specially with this awesome write up. Thanks for the great post. Very useful info.
You don’t need to pull the engine to access any of the ABC lines
Originally Posted by I drive a Ford
It had ABC (Active Body Control).
The pressure line blew which runs "underneath" the engine and would have required removing the engine to repair.
My Tandem pump burned up but it did not have a bracket. I still have the old pump but didn't take pictures of it.
It just has what I would call, "ears" that protrude from the housing with holes in the ends that you put the bolts through to attach it to the
engine. Sure would have been easier if it had a removable bracket I could have re-used on the new pump.
The Strutmaster's coilover conversion kit I purchased was excellent. Their instructions were excellent.
If there was no way to do a coilover conversion, this car was essentially scrap at the instant that pressure line blew underneath the engine.
Couldn't drive it, move it, nothing. It was flat on the ground. Hell of a time bomb that ABC system is!
I was able to pull all of the ABC components without pulling the motor.
this goes for changing them out as well.
you can easily support the engine, drop the subframe & pull all the front ABC lines & accumulators in an hour or two
the 3x rear lines & accumulators in the rear are harder than the ones up front:
now that I’ve done an ABC removal, I’m pretty sure I could change out & trouble shoot an ABC suspension in an 8 hour day.
You can drive on a fully compressed W220 suspension
Originally Posted by wallyp
Mercedes offered rubber blocks that went between the suspension and the chassis to allow you to move and even drive the car.
A friend bought rubber wheel chocks, tie-wraps and a hacksaw from a (very luckily convenient) Harbor Freight store and MacGyvered a workable substitute when an Airmatic strut failed on the road.
I used his rig to get an S500 home when I bought it with a failed rear strut.
you can drive your w220 with the suspension at full compression, you just have an extremely limited ability to steer with any excessive angle.
I just completed this procedure over the last week; including swapping the tandem pump for a "traditional" p/s pump. However, I have made height, dampening, and gone over everything to make sure it was installed okay, I am still getting a clicking sound when I turn the steering wheel while the car is not in motion. It is not very noticeable when turning the wheel to the left, however when I turn it to the right, it is more pronounced. When searching this problem, I found that it could be the spring binding or a bad bearing on the coilovers. I am not sure how this is possible seeing as they are brand new. I tested driving the car around and have even gone on the freeway. Nothing feels loose nor am I getting any weird vibrations otherwise. By the way, I was expecting something really terrible after reading how "bouncy" the ending result would be. I do not find it annoying in any way and feel the car is actually very stable. I did install sway bars when installing the coilovers so I do not know if this had any effect on mitigating that.
I just completed this procedure over the last week; including swapping the tandem pump for a "traditional" p/s pump. However, I have made height, dampening, and gone over everything to make sure it was installed okay, I am still getting a clicking sound when I turn the steering wheel while the car is not in motion. It is not very noticeable when turning the wheel to the left, however when I turn it to the right, it is more pronounced. When searching this problem, I found that it could be the spring binding or a bad bearing on the coilovers. I am not sure how this is possible seeing as they are brand new. I tested driving the car around and have even gone on the freeway. Nothing feels loose nor am I getting any weird vibrations otherwise. By the way, I was expecting something really terrible after reading how "bouncy" the ending result would be. I do not find it annoying in any way and feel the car is actually very stable. I did install sway bars when installing the coilovers so I do not know if this had any effect on mitigating that.
Unless your coil overs have ball bearing or pillow ball type upper mounts, you shouldn’t have any bearings on your coilovers.
What brand coilovers do you have?
if you are getting clicking when turning your wheel, when not in rolling/ forward motion, you likely have a worn component in the steering/ suspension.
clicking (when sitting still) can be caused by a bunch of different things.
Try to isolate where the sound is coming from by having somebody move around the car; listening to the sound & pin-pointing where it comes from, while you’re inside the car, turning the wheel (attempt to duplicate the sound with regularity)
im thinking you might have some wear tolerances that are stacking up, that the conversion might have made more obvious.
I have some questions that might help track the problem:
Brand of coilovers?
How many miles are on your car?
When was the last time the suspension bushings had been inspected?
When was the last time the wheel bearings were inspected?
When was the last time the brakes were inspected?
Did you install new or used suspension components, when doing the conversion?
When torquing your suspension components down, was the suspension loaded & ride height?
Did you drop the front & rear sub-frames when doing the conversion?
Did the steering column ever leave the steering rack, in the process of the conversion?
has the steering return/ clock spring been damaged?
Did you remove all ABC lines from the chassis, when doing the conversion?
Post video id possible, while duplicating the sound.
Unless your coil overs have ball bearing or pillow ball type upper mounts, you shouldn’t have any bearings on your coilovers.
What brand coilovers do you have?
if you are getting clicking when turning your wheel, when not in rolling/ forward motion, you likely have a worn component in the steering/ suspension.
clicking (when sitting still) can be caused by a bunch of different things.
Try to isolate where the sound is coming from by having somebody move around the car; listening to the sound & pin-pointing where it comes from, while you’re inside the car, turning the wheel (attempt to duplicate the sound with regularity)
im thinking you might have some wear tolerances that are stacking up, that the conversion might have made more obvious.
I have some questions that might help track the problem:
Brand of coilovers?
How many miles are on your car?
When was the last time the suspension bushings had been inspected?
When was the last time the wheel bearings were inspected?
When was the last time the brakes were inspected?
Did you install new or used suspension components, when doing the conversion?
When torquing your suspension components down, was the suspension loaded & ride height?
Did you drop the front & rear sub-frames when doing the conversion?
Did the steering column ever leave the steering rack, in the process of the conversion?
has the steering return/ clock spring been damaged?
Did you remove all ABC lines from the chassis, when doing the conversion?
Post video id possible, while duplicating the sound.
What brand coilovers do you have?
if you are getting clicking when turning your wheel, when not in rolling/ forward motion, you likely have a worn component in the steering/ suspension.
clicking (when sitting still) can be caused by a bunch of different things.
Try to isolate where the sound is coming from by having somebody move around the car; listening to the sound & pin-pointing where it comes from, while you’re inside the car, turning the wheel (attempt to duplicate the sound with regularity)
im thinking you might have some wear tolerances that are stacking up, that the conversion might have made more obvious.
I have some questions that might help track the problem:
Brand of coilovers?
Yellowspeed
How many miles are on your car?
Just shy of 100,000.
When was the last time the suspension bushings had been inspected?
At the shop I take it to about two months ago.
When was the last time the wheel bearings were inspected?
See above
When was the last time the brakes were inspected?
Replaced front discs and pads about three months ago.
Did you install new or used suspension components, when doing the conversion?
New control arms, new coilovers, used sway bars and end links.
When torquing your suspension components down, was the suspension loaded & ride height?
Yes
Did you drop the front & rear sub-frames when doing the conversion?
Rear only.
Did the steering column ever leave the steering rack, in the process of the conversion?
I don't see how it could have.
has the steering return/ clock spring been damaged?
It was replaced about five months ago. Idk how it could have got damaged again.
Did you remove all ABC lines from the chassis, when doing the conversion?
Not all of them.
Unless your coil overs have ball bearing or pillow ball type upper mounts, you shouldn’t have any bearings on your coilovers.
What brand coilovers do you have?
if you are getting clicking when turning your wheel, when not in rolling/ forward motion, you likely have a worn component in the steering/ suspension.
clicking (when sitting still) can be caused by a bunch of different things.
Try to isolate where the sound is coming from by having somebody move around the car; listening to the sound & pin-pointing where it comes from, while you’re inside the car, turning the wheel (attempt to duplicate the sound with regularity)
im thinking you might have some wear tolerances that are stacking up, that the conversion might have made more obvious.
I have some questions that might help track the problem:
Brand of coilovers?
How many miles are on your car?
When was the last time the suspension bushings had been inspected?
When was the last time the wheel bearings were inspected?
When was the last time the brakes were inspected?
Did you install new or used suspension components, when doing the conversion?
When torquing your suspension components down, was the suspension loaded & ride height?
Did you drop the front & rear sub-frames when doing the conversion?
Did the steering column ever leave the steering rack, in the process of the conversion?
has the steering return/ clock spring been damaged?
Did you remove all ABC lines from the chassis, when doing the conversion?
Post video id possible, while duplicating the sound.
so this happens when you remove the upper steering input spline from the lower steering column linkage that passes through the firewall.
tgat clicking sound is the clock spring skipping past its retainer, so to the wheel spinning freely, because there is no e gauge by with the steering rack.
Both you & I are in the same boat.
I didn’t have time to address the issue & I just put it all back together & I’ve been dealing with the non operational click spring.
it’s likely broken, but I haven’t pulled mine back apart to confirm.
it’s defiantly out of whack & either needs to be rebuilt or replaced.
so this happens when you remove the upper steering input spline from the lower steering column linkage that passes through the firewall.
tgat clicking sound is the clock spring skipping past its retainer, so to the wheel spinning freely, because there is no e gauge by with the steering rack.
Both you & I are in the same boat.
I didn’t have time to address the issue & I just put it all back together & I’ve been dealing with the non operational click spring.
it’s likely broken, but I haven’t pulled mine back apart to confirm.
it’s defiantly out of whack & either needs to be rebuilt or replaced.
Thank you for this information. I'm going to take it back to the shop I go to because they are the ones that replaced the clock spring. It is still under warranty.
Once the power steering hardline and fluid supply hose were attached, reassembly was otherwise normal. Since I aligned my pump spacers to the inside edge of the pulley on both pumps, I made sure to align the 6 rib belt leaving the rib closest to the radiator unused on all the other accessory pulleys.
After reassembly, I filled the PS reservoir to the top with Pentosin CHF11S, and jacked the front wheels off the ground before starting the engine. Immediately after engine start, I turned the wheel full left and full right and then shut the engine off. After this job, there will be a substantial amount of air in the PS system that must be bled. This needs to be done with no load on the wheels to avoid pump cavitation. After shutoff, I found the reservoir to be nearly empty again, so I refilled it once more. After this first time, it should monitored, but you won't likely suck any air. If you do suck air, you need to do it all over again.
After waiting awhile for air bubbles to settle out of the system, (A couple of hours, and this won't happen while the pump is running) I lowered the car and started her up. Everything works perfectly, just as it should. I've driven it about 200 miles before writing this up, just in case I screwed something up, or the idea didn't work out. From the driver's seat, you would never be able to tell any difference. The power steering functions exactly like it did when running the old tandem pump, the ratios and variable assist seem spot on. There are no odd noises, and the 6 rib belt drives the AC and charging system (the two highest load accessories) with no complaints. In short, it's a custom install that does not have any idiosyncracies or minor niggles to explain away. It works just as intended, and you'd never know unless you needed to replace a belt or something down the road. Result!
Since I've already done all the engineering work, this is actually not too difficult a mod to accomplish on your own V12 if you want to.
What you need:
1) Power steering pump off an air ride V8 car S430/500 (I got a pump off a 2001 S500, I don't know for sure if there are any variations in model years)
I recommend getting a used pump from Ebay or something. You will need the mounting bracket and pulley. New pumps I looked at didn't come with these pieces. My Ebay pump came with everything. Cost: $90 shipped
2) Custom fabricated hydraulic hose modification to original hardline. Cost: $65 + a 12 pack of beer for the shop. Use my pics so they know what you're talking about.
3) 4 spacers, machined from bar stock. I used steel, aluminum would work too, I guess. They are all .750" diameter, and two of them are 1.375" long. The two smaller ones are different thicknesses from each other. I'll edit this later when I find where I wrote the dimensions. All these are gun drilled with a .325" hole down the center to fit an 8mm bolt. You'll also need your version of my good friend Joe with a lathe to make these for you.
4) 3 new mounting bolts, 2x M8x70mm, and 1 M8x60mm, and a couple a washers. About $5 at Lowe's
(The metric hardware selection at Lowe's is way better than Home Depot)
5) Dayco belt part #5060923, about $35, in stock at Autozone.
With the spacers already made and in your hands, you can swap the pumps out fairly quickly. Getting the tandem pump out is the worst part of that job. The most time consuming part is extracting the hardline and having the custom line fabricated. Once you get that back in, easy.
Total cost: About $200, all in.
is the V12 in a 04 SL600 the same block as you have in your PS conversion?
Last year we started offering a bolt-in V12 power steering pump with the correct 7rib belt and the correct clamp-type elbow fitting to connect to the factory reservoir hose. I forgot to mention it here.
09-10-2018, 01:27 PM
From the driver's seat, you would never be able to tell any difference. The power steering functions exactly like it did when running the old tandem pump, the ratios and variable assist seem spot on. There are no odd noises, and the 6 rib belt drives the AC and charging system (the two highest load accessories) with no complaints. In short, it's a custom install that does not have any idiosyncracies or minor niggles to explain away. It works just as intended, and you'd never know unless you needed to replace a belt or something down the road. Result!
