How to: Update the Power Steering tank on a 355

So, there have been a couple discussions about how the early style power steering fluid tanks fail. The cap blows off, especially at high RPM. Blows power steering fluid everywhere. Nasty. Possibly a fire hazard etc etc.

I decided to update my power steering fluid tank, and took some photos along the way.

Before I get started: a little research turned up that the same manufacturer "ZF" who makes the Ferrari tank, also makes a BMW tank of the same dimensions. Being a BMW part, it's available at a fraction of the cost ($21 vs. $148). There is one extra detail on the side of the tank, but it still fits just fine.
http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=32-41-1-097-164-M103&catalog_description=Power Steering Fluid Reservoir, BMW E30 3 Series, All (1984-92), Each

You can see the Ferrari part and the BMW part (both made by ZF) in the photo below.
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Step one: remove the 6 10mm nuts holding the plastic cover over the coolant tank and power steering tank. By the time I took this photo, I'd removed it already.
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remove coolant from the overflow tank. Here I'm using a Mighty-Vac to drain the coolant by pulling it into a brake bleeder bottle.

If I had to do it again, I might have tried to do the whole thing without removing the coolant tank. Does make it a heck of a lot easier to get to the hose clamps on the PS tank.

I forgot to photo it, but I used the same technique to get the power steering fluid (actually, it's ATF) out of the PS tank.
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remove the upper hose clamps from the coolant tank
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Remove lower hose clamps from the coolant tank
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Before removing the coolant tank, get about 10 paper towels, or a couple rags, and lay them under the tank. No matter how careful you are about getting all of the coolant out of the coolant tank, you will get at least a small amount of coolant spilling. Also, the lower hoses are going to still be full of coolant. As soon as they are disconnected, they have to be nudged into a vertical position and tucked behind the mount for the power steering tank. They're the larger hoses pointing skyward at the left and right side of the tank in this photo.

Completely draining the coolant would avoid the messy part.
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unbolting the empty power steering tank
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The original bracket that holds the older style power steering tank, has two tabs that hold the tank in place. Ferrari offers a new bracket that doesn't have these tabs.
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Or, you can save about $60, by just bending them out of the way.
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Here's a comparison of the original tank and the updated ZF tank (the BMW version).
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Any time you have a molded plastic part (like this tank, or a plastic fuel filter for a motorcycle), you're likely to end up with a seam right in the middle of a place where you want to make a good seal. I'm pointing to the seam here. Before I installed the part, I took an exacto knife and shaved the seam smooth. (not the barb at the end, but the tiny seam running up-down)
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Here's the tank, set into place. The blue coolant in the hose near the camera is just waiting for me to bump the hose and spill some more.

The location of the hoses on the bottom of the updated tank is different from the early style tank. This means that if you try to install the tank so that the inlet/outlets are located exactly side to side, the larger hose is going to end up being too far to the left and thus too long. The extra length will make the hose try to kink. Rotating the tank slightly to the left gives the hose (the oily one with the loose hose clamp) enough space. You could also shorten the hose.
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The bracket holding the steering fluid tank didn't hold it as tightly as I would like. It's possible that the new bracket from Ferrari addresses this, in addition to not having the extra two tabs that stick out.

Would have worked just fine as it was, but I like things to stay put, so I applied some thin closed-cell weather stripping. I actually cut it to make it even thinner than original. Didn't need to take up much space. I would recommend using a little more weather stripping than shown here.
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Here's a shot of the tank installed
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Now is also a great time to lube your throttle linkeage. I just used some Mobil 1 synthetic oil I had in the garage. I dipped a small screwdriver into the Mobil 1 and put a drop or two on the pivot points.

Also a good time to clean up any spilled coolant. (the Power Steering fluid, surprisingly didn't spill at all, but I did get it all out of the tank.)

This is also a really good time (if you planned ahead, like I didn't!) to do the Dave Helms Silicone hose update, for the two hoses that connect to the top of the rear of the coolant tank. The inside diameter of these hoses shrinks over time, down to about nothing. My hoses only have 1,300 miles on them and were clean and clear inside, so I left them for now. I will be ordering silicone replacements though.
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Here I've re-installed the coolant tank. If you look closely, you'll see the two small diameter hoses running past the left and right sides the power steering tank. These are the ones I was talking about above. If you compare this shot to the first one, you'll see that I've re-routed them above the bracket for the power steering tank. I had to shorten them an inch or two to do this.

Why did I re-route them? These hoses let air bubbles and steam escape the cooling system and return to the coolant tank. The way they were routed before, the hose went: up, then back down, then up again. Not a good way to encourage bubbles to go home. When I had them disconnected, and moved the left one upward, I could hear the system burping, and burping. So the previous routing wasn't letting it burp very well. Now they go up monotonically as they approach the coolant tank.
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And there we go. All back together. Filled the power steering tank with Dexron ATF until I just got a reading on the dip stick. (owners manual calls for Dexron Automatic Transmission Fluid) Dexron is apparently not a brand, but a type. Many companies make it.

Filled the coolant tank to the normal level.

Then ran the car with the heater on full until the cooling fans turned on, then topped up the power steering fluid. Heading out to top up the coolant now (since it has had time to cool while I've been typing this
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I'll report back after I've put some miles on.

One thing about spilling some coolant while doing this... it makes it a lot harder to tell if you've caused a new leak.

 

Thanks guys!