I had my 87 at the track the other day. Only got about 10 laps before huge power steering fluid leak ended my day. I think the input shaft seal let go, must be a common problem on these, time to swap in a rebuild rack.

The car has base suspension. I want to swap in the quick rack. Local parts store shows standard or Z52 as options. I thought the quick rack would be listed as Z51. They have no reference to Z51 in the computer. I ordered the Z52 rack, if its not 2 turns lock to lock I probably will not take it when it comes in.

What is the difference between the Z51 and Z52 codes? Any suggestions on where to get the quick rack if the above doesn’t work out? Will I need to change any other parts to make the swap?

Z52 is a Z51 with softer springs.

What track did you run?

http://www.corvetteactioncenter.com/specs/c4/1987/87prod.html

no other parts, but if the rack is bad, consider new tie rod ends, too.

I am not aware of seal failures being a major problem. I do know that hoses are a bit of a weak link. I would get a pressure washer in there and really clean up the area, too. ick-poo... it gets gnarly down there.

Be careful with those remans, it can be a crapshoot on what turn racks go in which box, and the codes on the cap mean nothing after they're rebuilt... so test it with some vice grips before you take it home.

The track was mid american at Pacific Junction, Iowa. I cant tell for sure where all the fluid is comming from, I think it the rack because i had a slight leak there before. While i'm in there i want to do the hoses, tie rods and maybe the pump.

When my rack went it was bypassing fluid internally, and just sort of groaned and took more effort to turn it. Adding lucas made it 10x worse and finished it off.

It's not damp anywhere above the rack? I had issues with ps fluid blowing out the vent hole in the reservoir.

This is what has me concerned. I assume its the rack but you know what happens when you assume. The way it blew fluid everywhere its hard to say for sure where it came from. I did have a moderate drip around imput shaft/hose connections(connections tight). I added lucas and it seemed to help, hoped it would make a few more days. My thought was that it finally let go.

Maybe when i tear it apart i'll know more. Is the vent in the reservoir lid? I wonder if the problem could be related to sustained high rpm. How did you fix your problem?

Well, fluid always goes down... and sprays everywhere. So if it's up that high, it's probably not leaking from below.

High rpms caused the fluid to foam up... the entire reservoir bubbles up and it dribbles mist out and blows all over. The fix was to use semi-syn fluid AND a LT1 cooler. The stock pump, in 85 at least doesn't handle the sustained high rpms well.

^^Interesting, you'll remember mine has a leak here......I've replaced all the hoses and the leak still persist.

I've just given up until I have the money for a new rack.

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I started pulling things apart this afternoon. I pulled the pump off first. Found that the suction hose from the reservoir to the bottom of the pump might be my problem. The hose was old and hard and the clamp at the pump was not at all tight. I don’t know if I need to change the rack. Hate to spend the money if I don’t need too but I don’t want to waste another day at the track to the same problem. I can put it back together with new hoses and try it on the street but it wouldn’t surprise me if it’s fine there and leaks at the track.

A leaking suction hose will allow air to enter the lines. There's negative pressure so it won't actually leak there while driving, it would only weep a little after parking it. In fact I think that was exactly why my fluid kept foaming up.. it was pumping air bubbles through the system. It was a $25 part that I might have ordered from corvettecentral, the formed hose. I don't think a regular hose can safely make those bends.... maybe with ez-coils.

Very good point, I hadn’t thought about the negative pressure. I wonder if the bad connection caused my fluid to become aerated leading to my problem. I was thinking about using braided steel and hose clamps for replacement.

Stock rubber is fine, how long did this one last? I actually had a hard time getting a good seal at the reservoir, since the connections have casting flash, even with smoothing them out. The oil foaming out the top tends to soften the hoses too and makes em leak more. What good will a stainless braided hose do if it's still clamped to plastic? The 85s are plastic at least.

Whatever you do, don't use coolant hose or goodyear hi-miler hose.... it won't work.