[DIY] Power Steering

[Steve Pratel]

I'll be doing this over the next week or so. All OEM parts, the two lines and resevoir. Hope to get another 15 years out of them. Confirm that the lines in and out of the resevoir are low pressure. Had I seen this I may have done the mod on the one line, but I'm trying to keep this car as 100% stock as I can. Every other car I have I modify, chop, alter, etc. But this M-3 will stay as stock as possible, with higher performance parts, rotors, pads, bushings, shocks, but I'm not going to do fan deletes, airbox mods, hose chopping, calip[er and rotor swaps, radiator/cross model parts. My goal is to keep it as pure as possible.... Gotta have one at least vehicle that way. lol.

[jayjaya29]

Lines in and out of reservoir are indeed low pressure.

[BANKAIm3]

Please see attached photo.
I'm not familiar with how hydraulic are assembled or how it looks on the inside.

I am planning on cutting just the "cup" that surrounds the hose and peeling it apart.
Does it look like I am on the right track here? I am planning on doing this mod this week. My last point of leakage on the PS system.

[jayjaya29]

Yep. Only on the line from the reservoir to the pump and from the rack to the res.

[crashgordan]

Following

[BANKAIm3]

Yep. Only on the line from the reservoir to the pump and from the rack to the res.

I'm only planning on doing this to that specific hose i referenced in the I picture I attached on my previous post. It is the hose that connects from the trombone (ps cooler) to the reservoir.

[jayjaya29]

I'm only planning on doing this to that specific hose i referenced in the I picture I attached on my previous post. It is the hose that connects from the trombone (ps cooler) to the reservoir.

Cool, go for it. Dremel cut off wheel is what I used. Clamp came right off.

If you are going to use a new rubber hose, make sure to transfer the restrictor valve from the old line into the new one.

[BANKAIm3]

Cool, go for it. Dremel cut off wheel is what I used. Clamp came right off.

If you are going to use a new rubber hose, make sure to transfer the restrictor valve from the old line into the new one.

I am not replacing that line. I am replacing the line that goes from the power steering cooler (trombone) to the reservoir.

[ewrjontan]

In this diagram http://www.realoem.com/bmw/diagrams/n/q/3.png

You are referring to the hose around number 9 that connects to 8 aren't you? That is the hose with the restrictor valve and the one that you need to cut with the dremel.

[jayjaya29]

Yeah there is a restrictor in the hose that goes from the trombone to the res. I can see the hose clamp in the middle of the hose that keeps the restrictor in place.

[BANKAIm3]

In this diagram http://www.realoem.com/bmw/diagrams/n/q/3.png

You are referring to the hose around number 9 that connects to 8 aren't you? That is the hose with the restrictor valve and the one that you need to cut with the dremel.

Yes, I believe we are referring to the same hose, but where is the restrictor valve? The current hose that connects to the trombone to the reservoir looks like just plain hose. There was a restrictor on line #5 that I replaced with an OEM replacement.

[blizzard424]

The restrictor on hose 9 comes with the hose. It doesn't have it's own P/N.

I believe some of the older models did not come from the factory with the restrictor. My '98 had one that I transferred to the new hose when I replaced it.

[jayjaya29]

The restrictor on hose 9 comes with the hose. It doesn't have it's own P/N.

I believe some of the older models did not come from the factory with the restrictor. My '98 had one that I transferred to the new hose when I replaced it.

+1

[BANKAIm3]

The restrictor on hose 9 comes with the hose. It doesn't have it's own P/N.

I believe some of the older models did not come from the factory with the restrictor. My '98 had one that I transferred to the new hose when I replaced it.

I see one on the #5 hose. I have a '98 and it doesn't have one. My #5 hose however, does have one.

- - - Updated - - -

It seems this thread is almost turning into a restrictor vs no restrictor debate... hahaha

[ewrjontan]

If you look at the picture you attached several posts up, you will see that the hose we are talking about (that connects to the reservoir and trombone) has a hose clamp (the one time use style). That is where the restrictor is. Snap/cut the clamp and the restrictor slides right out. Put it in your new hose and secure it in place with a new hose clamp.

[jayjaya29]

Just cut into the hose in question when you do the DIY. The restrictor valve will be there...

Or just reuse the hose with the restrictor in it. Just need to be careful when you are dremelling off the factory collar clamps.

[mjm0802]

Your inbox is full but mirrors still available

[hide1]

Just curious.. has anyone tried a simple power steering delete? This is common in most other crowds but doesn't seem as popular here. It seems that it would free up some power and eliminate all the frustrating source of leaks..??

[CMG]

Any power freed up from the engine would be transferred to ur arms.

[E36forever]

Just curious.. has anyone tried a simple power steering delete? This is common in most other crowds but doesn't seem as popular here. It seems that it would free up some power and eliminate all the frustrating source of leaks..??

I have and it makes steering WAY too hard. It's also not just a simple drain the fluid and cap off the ports and get a shorter serpentine belt either. Yes, it works for the Miata guys but not us.

After trying it years ago I have loved my power steering sooo much.

[hide1]

I have and it makes steering WAY too hard. It's also not just a simple drain the fluid and cap off the ports and get a shorter serpentine belt either. Yes, it works for the Miata guys but not us.

After trying it years ago I have loved my power steering sooo much.

So did you cap the lines, loop the lines, or use a power steering delete kit? Not all methods created equal here.

For example, simply taking off the belt would free up power on the motor but is not good for you and not good for the rack. The fluid is still trapped in the rack, and you are fighting against a non-moving pump. This is bad for the rack and it will not last long. Eventually the seals will blow, the rack will fail, and it is a lot of work to turn the wheel because you are fighting the fluid in the rack + grip of tires + weight of vehicle.

If you loop the rack and cut out the pump, you still have a system with trapped air mixed with the fluid making it hard to turn but better on your seals.

If you get a kit like the one from condor speedshop and only keep the needed amount of fluid to lubricate the rack, fluid and air will freely move back and forth, and then it will be a lot easier to turn. Seals are good as there is no pressure in the system and rack life is not compromised. No pressure, no leaks. .

I did this in the past but also included a tee fitting and a small Tilton Engineering reservoir for the fluid and air to have a place to 'breath'. Once the breather was on the car it almost felt like it had power steering again, low speed turning included.
(https://www.pegasusautoracing.com/pr...p?Product=3558)

Some people who have only pulled the belt or capped the system don't realize the difficulty turning without power steering is due to the force of overcoming the trapped air and fluids in a sealed system (plus non-functional pump) trying to make its way from one side of the rack to the other. I'm just throwing this out there to see if anyone else has experience with a breather on our cars, as its pretty simple fix and imagine it would be a good way to avoid constantly replacing hoses and fittings on a high pressure sealed system prone to leaks. .

[E36forever]

^Like I said it's more than just just draining the fluid and capping the ports. The breathing wasn't how I did mine but I suspect the results would be similar. You need to remove the rack from the case and cut out the middle collar (just like the Miata guys do). This will free up the movement of the rack itself. Again, go ahead and see for yourself but you won't like the end result. No one has with these racks that I have heard of to date.

Bottom line the root cause for the PS line leaks are bad motor mounts. Even stock won't be good enough. Once you upgrade the motor mounts and refresh the lines at the same time you will be in good shape.

[NeilM]

If you get a kit like the one from condor speedshop and only keep the needed amount of fluid to lubricate the rack, fluid and air will freely move back and forth, and then it will be a lot easier to turn. Seals are good as there is no pressure in the system and rack life is not compromised. No pressure, no leaks. .

It should be possible to delete the pump, retain the standard PS fluid reservoir, and route two hoses from it to the two fluid fittings on the rack using suitable adapters. That would keep the system lubed and self-bleeding, allow the fluid to move freely, and all at minimal cost.

That said, cars that are designed for manual steering usually have different steering geometry to keep the effort reasonable. That's not the case here, so better stock up on canned spinach and prepare to develop some Popeye forearms.

Bottom line the root cause for the PS line leaks are bad motor mounts.

No, the root cause is that the stock hoses to the reservoir are not quite long enough. The result is that even with brand new motor mounts, perfectly normal movement of the engine tugs on the hoses and eventually loosens them at the reservoir nipples. If the hoses were even an inch longer this wouldn't happen.

You can minimize, but not totally eliminate, this effect by carefully clocking the reservoir in its clamp in order to allow the greatest possible slack in the hoses. (You can only see this properly from under the car.)

Neil

[E36forever]

^Correct but like I said with "upgraded motor mounts" this won't happen. Most people either have worn OE mounts or new, but neither solve the issue as you already pointed out.

[NeilM]

^Correct but like I said with "upgraded motor mounts" this won't happen. Most people either have worn OE mounts or new, but neither solve the issue as you already pointed out.

Yeah, could be. But with upgraded (meaning stiffer) mounts there's a price to pay in NVH. Mine's a track car and still uses stock mounts. Not the original stock mounts, mind you...
;–)

Neil