Related question: reservoir connections (for the PS hoses)

[Stevehose]

I’m installing @alprada70 ‘s work of art and can’t quite remember if it goes on this side of the motor mount? Note the oil pan is off so it’s easy to see. I don't remember it going over the motor mount nut on the other side. Thanks.

 

[Stevehose]

Update:

I found a picture I took earlier, it looks like it goes on the other side:

Case closed.

 

[HB Chris]

It shouldn’t be anywhere near the motor mount. It follows the steering box and heads towards the fender and drops down to the pump.

 

[Stevehose]

It shouldn’t be anywhere near the motor mount. It follows the steering box and heads towards the fender and drops down to the pump.

Right, I see that now and it does clear it on the fender side. All good, thanks.

 

[Stevehose]

Ok how about this, the diagrams for E9 and E12 are different regarding the hose connections at the PS reservoir. E9 has the spigot going to the pump, E12 has the spigot going to the box, which is it, or does it matter? I would think E12 makes more sense as the returning fluid goes into the container before going through the filter and out the bottom hole but of course I didn't take a pic of mine before removing the hoses. Or is the fluid in the reservoir filtered before it is stored?

 

[HB Chris]

Both high pressure hoses with the crimp go to pump in same location, it just doesn’t show e12 steering box.

 

[Stevehose]

Both high pressure hoses with the crimp go to pump in same location, it just doesn’t show e12 steering box.

I'm referring to the low pressure hoses at the reservoir - the diagrams show them attaching at opposite places.

 

[wkohler]

Does this help? It’s okay to say no. I can take it.

 

[Stevehose]

Does this help? It’s okay to say no. I can take it.

yes - so your low pressure hose from the reservoir bottom center outlet (not the spigot one coming out of the side) goes to the pump which is correct for the E12 diagram but opposite of the E9 diagram. We all know that those diagrams can’t be trusted (fan clutch for example) so I am leaning towards this setup as it makes more sense flow-wise.

 

[wkohler]

Oh I guess I could have answered this simply. I must not have understood the question.

If you look inside the reservoir under the plate over the filter, return comes into the port on the side and then the center feeds the pump. The feed hose has a larger ID than the return as well.

 

[Stevehose]

Oh I guess I could have answered this simply. I must not have understood the question.

If you look inside the reservoir under the plate over the filter, return comes into the port on the side and then the center feeds the pump. The feed hose has a larger ID than the return as well.

Right, so the E9 diagram is backwards.

 

[Stevehose]

Oh I guess I could have answered this simply. I must not have understood the question.

If you look inside the reservoir under the plate over the filter, return comes into the port on the side and then the center feeds the pump. The feed hose has a larger ID than the return as well.

Later 5 and 6 series show the same as the E9, meaning the side port supplies the pump, not the steering gear box. So only the E12 has it going the way in your picture. Nothing in the manuals that I can find. Any other definitive confirmatin either way?

 

[wkohler]

Luckily, I’ve owned a few E12s. Fortunately I’ve done some stuff with them and sadly I sold the Golf one because I’m stupid.

Here’s the 1975 530i. You’ll see the hose on the side of the reservoir goes to the steering box so it’s the return. The hose that comes off the bottom goes straight down to the pump.

Here’s the subframe from my E12 M535i after I removed it from the car and put it on dollies.

Hope this clears it up. I was just at the shop with my E9 reservoir and meant to put the calipers on the two ports as IIRC the feed hose is 16x22 and the return is 12x18.

 

[HB Chris]

All I know is the side port feeds the pump and fluid returns from the steering box underneath on an e9. My 79 528i is exactly the same.

 

[Stevehose]

The hose that comes off the bottom goes straight down to the pump.

Despite the E9 and other model RealOEM diagrams, I have switched to layout in the E12 diagram, it makes sense that the return should go to the unfiltered part of the reservoir and that the pump should pull fluid through the filter straight down from the can. Otherwise the fluid would swish around the reservoir and possibly pick up contaminents after being filtered on the way in from the steering box. Regardless, I don't think there is a huge risk doing it the opposite way.

 

[wkohler]

Plus makes more sense to me that the feed is in the lowest part of the reservoir.

 

[HB Chris]

My e12 is like all e9s I have seen, it does not match the RealOEM e12 diagram, it feeds pump from the side. Fluid returning from the box is pushed up through the filter into the reservoir.

 

[boonies]

Interesting, I wonder if the density of the filter media is such that pressure is needed to force it thro to the pickup.

 

[HB Chris]

Interesting, I wonder if the density of the filter media is such that pressure is needed to force it thro to the pickup.

Perhaps, it is very solid.

 

[Stevehose]

or maybe it's to let gravity feed the pump without making the pump use suction to pull it through the filter first. I dunno it's kind of stressing me out I've looked at the filter closely before, it's made up of a structure of rather large cells that passes light, rigid like Chris says, likely because of the viscosity of the fluid.