About two and a half years ago, I rebuilt my steering rack with all new bushings and seals. I installed it and ran fluid through it and everything looked good, no leaks. My Corvette is a project car, so I had no front suspension or anything connected to the steering rack. Last summer, I noticed the rack was leaking from the boots that cover the inner tie rods, both driver's and passenger sides had fluid in them. I could squeeze one boot and hear air and fluid come out the other side. Today I took the rack apart and looked at all the seals and none showed any damage. I checked the steering rod for straightness and any scratches along with the tube, and didn't find anything.

I'm wondering if the outer seals had a slight leak since there was no real pressure on them and they sat for so long? I'm thinking how a piston ring seals from compression pressure, that the rack seals didn't really "seat" against the rod, because there was no pressure on them? I'm at a loss for what would cause it to leak.

 

I remember that thread and left thinking, .....how long will this last. Many concerns with the quality of the seals, seals stretched out of shape, and no mic/caliper to be found to confirm the mating surfaces were in spec......not to mention the seals. Kudos to you for giving it a shot though. Hopefully the postmortem will reveal the offending area.

 

I think I found out what my problem was.

TLDR: I damaged the inner rack rod seal when installing the steering rod.

I checked the lower pinion seal for damage, and it looked fine, no damage there. The last seal I removed was the inner rack rod seal. The socket I used to push it out was too small, so I pushed the socket through the seal. When I used a bigger socket and pushed it out, I noticed the seal was damaged, but I thought I had done that on my own. In this picture, the socket would be pushing down on the green plastic side, and you can see the seal has a chunk missing on the top.


When I flipped the seal over, I noticed that the seal was damaged on the inside. When I pushed the socket through, the socket would never have contacted the back side of the seal, so I started looking at what could have caused it. At first, I thought it could have been the teeth on the steering rod, but those don't protrude out, so they couldn't have done this either.


Looking at the end of the steering rod, the edge where the inner tie rod goes in is thin and sharp enough to have cut the seal. I think while I was installing the rod, the end caught on the seal and damaged it.


Then I started to wonder, if only the driver side seal was damaged, how did the passenger side boot have oil in it too? I have a second steering rack I bought with some suspension parts from a junk yard and pulled it out to see if maybe I put the passenger side seal in wrong or backwards. I have no idea if this second rack also leaked, but when I squeezed the boot on one side, I could see that the other side would puff up a little from the air pressure. I took a look at the steering rod and noticed it was hollow, but not all the way through to the other side. I took a coat hanger and put it down the rod, and it stopped right where the hole is drilled. So if the middle rod seal on the right is leaking (the driver's side - the rack is flipped in this photo), then the oil would flow down this vent to the passenger's side.


So I think I found my problem and will replace the inner rod seal. I'm going to make something to cover the rod end and be more careful installing it. I now know more about the inner workings of a steering rack then I thought I would :-)

 

Thanks for sharing with us, glad you found what appears to be a smoking gun, and hoping that will fix it for you.

It's nearly 3 years and 7.5k miles since rebuild, no signs of leaking yet.
No seals were stretched out of shape, unless you're referring to the teflon scraper rings... which HAVE to be stretched to slide into place.
Let's say I mic'd various surfaces; how would I know if they "were in spec"? I've never seen specs for these parts. Not to mention I'm plenty capable of visually checking parts for wear, and saw no wear marks.

I'm trying to not take your post personally... it just feels really negative and anti-DIY. Feel free to post up something better.

 

Sorry I triggered you. I'll steer-clear of your posts in the future.

 

I got the replacement center seal yesterday and assembled the rack. Before putting it back together, I sanded the edge of the rod that will go through the seal with 2000 grit paper and WD-40 to round out the edge a little. I greased the end of the steering rod and also mounted the rod vertically in a vice on the ground. I lowered the steering housing down over the rod so I could look down the steering housing and see the rod line up in the middle of the seal before pushing it through. I'm going to mount the rack in the car today without the tie rods or boots on so I can check for leaks right away.

 

How'd the re-do turn out?

 

It looks good so far. I installed the rack and ran the motor a couple of times. I put a strap across each end, one at a time, so the rack would be under some pressure when turning and nothing is leaking. Even after sitting for the weekend, not a drop, so it looks like the fix worked.

 

Thanks for the follow-up

 

Agreed! I'm hoping for additional/continued long-term follow-ups as well