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Mountain-Metalworks
07-18-2017, 10:29 PM
I have conflicting info in my library of information I stored prior to starting my build in regards to feed vs return line on the PS rack. I've looked at a couple build threads and 99% sure I have it correct, but can I please get a quick confirmation that I have the feed and return lines installed correctly.

A saved pic from what looks like a service manual(leak diagnosis chart) has the top line as return and the bottom as feed. I believe that is incorrect and the top line is the high pressure feed from the pump like I have installed below. My installation pic has the line on top coming from the PS pump, the line on bottom goes to the small cooler and then back to the remote reservoir.

http://thefactoryfiveforum.com/attachment.php?attachmentid=70801&d=1500433686

The reason I'm asking is I have a really weird situation when I try to turn the tires to the right. Engine has never been started, therefore pump has never run. Prior to adding fluid to the system I could turn the tires relatively easily in both directions(what you'd expect from an unpowered rack). After adding fluid, if I try turning the tires to the right, it severely binds after 1/4 turn of the wheel. If I release the force on the wheel, it will then easily turn another 1/4 turn then bind again. I can do this until turned all the way to the right. If turning to the left, no binding at all for the entire sweep of fully from the right to fully to the left.

Again, this is a system that has fluid but the pump has never run. Do I need to wait until I run the pump before making any conclusions? I saw a Roadster's first start that had the lines reversed and it violently shook the steering wheel once the pump started pumping. Is this what I'm going to see upon first start(hopefully within the week....)?

Thanks,

-TJ

rich grsc
07-19-2017, 02:45 AM
Sorry but the way you have your lines are incorrect. The top port is the return line, the bottom port, the inlet. The small line will almost always be the high pressure line, the large line the lower pressure return.

70813

Joecobr
07-19-2017, 04:09 AM
I have the exact same setup, cooler and all...my top port, return, connects to the cooler.

edwardb
07-19-2017, 06:36 AM
Yup, backwards. Bottom port is the pressure line from the pump. Top port is the return line, through the cooler before going back to the reservoir.

Mountain-Metalworks
07-19-2017, 08:28 AM
DOH! Well, hope I didn't make my lines a perfect fit and too short for the correct location. Rich, that's the picture I had but for a couple of reasons I thought it was wrong. Anyhow, I hope getting them correct will fix the weird binding problem I have right now.

Thanks for the confirmation guys!

-TJ

ThickCobra
07-20-2017, 08:09 AM
DOH! Well, hope I didn't make my lines a perfect fit and too short for the correct location. Rich, that's the picture I had but for a couple of reasons I thought it was wrong. Anyhow, I hope getting them correct will fix the weird binding problem I have right now.

Thanks for the confirmation guys!

-TJ

I had the same problem with it binding while turning the wheel...before I had it powered. Turn a little and bind, let off, then turn a little more. Discovered I had them backwards and you know the results on first engine start. Then I had to purchase a new rack as the damage resulted in a seal failing. As a bonus, I also discovered that Ps fluid and new asphalt don't get along and fluid always wins.

mosh1999
07-20-2017, 04:27 PM
I deal with customer's questions about rack & pinions all the time. From the average installer, to the employees at the car shows you see on TV, and custom racks for cars being built for the movies. Make sure the lines are not reversed.

As mentioned above by jeepurz, the steering wheel will often turn violently on its own as soon as you start the motor. People have been hurt when they are building a car and don't have a windshield. They will stand outside the car, bend over to reach the carb and put their arm through the steering wheel to start it. The wheel can turn fast enough to break an arm. The second issue is that it almost always blows out the pinion seal. It may not leak at first, but eventually you will need the rack rebuilt. When it leaks, it does so profusely.

Todd
Unisteer

ThickCobra
07-20-2017, 06:48 PM
Mine could have did turn violent. Jeepurz, thanks for "outing" me. Just ribbing ya'

2bking
07-20-2017, 09:10 PM
Yep, I guilty of line reversal and had to buy another rack. I thought I shut it down in time to save the rack but over the next week most of the PS fluid ended up on the floor. Mine leaked out the rack ends as well.

Mountain-Metalworks
07-21-2017, 01:24 AM
Mine could have did turn violent. Jeepurz, thanks for "outing" me. Just ribbing ya'

Nobody would have known just "who's" car I saw started with the lines reversed had you not mentioned it Jay! Just sayin'.... I was trying to be discreet. :D


Yep, I guilty of line reversal and had to buy another rack. I thought I shut it down in time to save the rack but over the next week most of the PS fluid ended up on the floor. Mine leaked out the rack ends as well.

I'm SOOOO glad I recognized the weird situation prior to starting and questioned the lines since replacing a brand new(although cheap) rack would not have been a part of my plan. One more kudos to the forums for saving me from a potential mistake! If I had a radiator right now it would have been too late, I'd have already started my engine and boom goes the rack. I guess I have to sarcastically thank Afco for over promising(and under delivering....) on my custom radiator!

-TJ

ThickCobra
07-21-2017, 06:44 AM
Jeepurz,
Oops, I guess I "outed" myself. Well, I hope others have learned from my mishap as I believe that's the best part of this forum. On a positive note, with the help of friends, my body goes on for the final time this Saturday. Then everything else comes together, windshield, exhaust, door, hood and trunk panels. I'm between house projects so now the next few months will be dedicated to getting the car road worthy and licensed. Painting will be later.