Power to Manual Steering conversion?

[VaSteve]

I was under the car the other night fixing something else and noticed that the hose on the back of the P/S pump appears to be loose. I was tired and didn't pursue it further, but I am assuming that it doesn't work (or doesn't work well) since the records have stated that the p/s rack needed to be replaced.

Is there any reason I need to replace this with a manual rack? (I'll be using is as a track vehicle). Could I just take of the pump, reservoir and use the ex-power rack as a manual rack?

[nynor]

not really. you will need the manual rack, tie rods, manual steering shaft, among other things.

[yellowline]

Different steering ratios, I'm not sure if it would have the same feel and precision of a manual rack.

There's an auction for a manual steering setup kit on the 944 section of Rennlist. They can be found.

[Zero10]

You need to leave the other components in to keep the system full of fluid, or else bad things will happen.
If you do this, you will stress the intermediate shaft badly, and I would worry about long-term failure of the U-joints in that shaft. Mine had 0 play in it when I bought the car. The power steering pump broke, so I unhooked the belt and ran manual steering for a while, and now there is a LOT of play in that shaft. enough to really worry me.

[BananaClip]

as posted, the gear ratios are wrong for that. you really need a dedicated manual rack or it will be way too hard to turn.

[JivenJim]

I'm Running a P/S Rack with No Fluid and Belt removed. Drives great and I feel more connected to car. I do plan on adding some fluid and doing a closed loop for Rack Lubrication.
1500 miles, so far so good.

0-5 MPH takes some firm but manageable effort.
5-15 Mild+.
30+ feels the same as PS.

Now if you got much bigger and sticky tires I would think then you better shell out for that gear reduction like on a manual rack or have some big arms!

Just pull the belt and see how it feels first!

Feels really good to dump a bunch of those hoses in the trash.

[Eldorado]

i agree with a poster up there ^^^^^ (too lazy to scroll up)... a power rack was meant to have assistance from the pump.. without that help, you're putting undue pressure on all the moving components of the rack.. sure it might run fine for a while.. but over time, you could potentially really start to bind up in there... could be months.. could be years.. i couldn't really begin to tell you...

[speedracing944]

Chitown944 was over at my house so we could do his belt tensioning. His power steering pump was leaking so he decided to remove the belt. I test drove the car afterwards and noticed little difference compared to my manual rack 83. You could try to email him to see if he has had any slop issues. It was a year ago.

Speedy

[VaSteve]

Originally posted by yellowline

There's an auction for a manual steering setup kit on the 944 section of Rennlist. They can be found.

That's what got me thinking about it. I may hold out till Hershey though...


Thanks for all the advice. Never thought of the different gear ratios.

[Zero10]

Seriously, it's very hard on the U-joints in the intermediate shaft.
Everybody who does the power-manual conversion without switching racks should regularily inspect these for excessive play. If one of them lets go, you no longer have any steering. I will be replacing mine next year when I bring the car out of storage.

[EA425]

Seriously, it's very hard on the U-joints in the intermediate shaft.

What is this "intermediate shaft"? Does it link the steering column to the rack? Can just that part be replaced (with it's weak u-joints) without the need for installing the complete manual rack? thanks.

[Zero10]

Nope.
Manual rack is shorter, intermediate shaft is a different length.
That's why it's required to swap to the manual rack.

[JivenJim]

Good Safety Points,

Zero10, Do you know if the Shaft or joints have different thickness besides being shorter on the Manual. Got me to thinking about that development of play issue. I have a hard time believing those u-joints on the Intermediate shaft are stretching any more than any other manual rack and making play. I would love to dissect one of those PS rack "with play" and know exactly where it's coming from. I've heard the rack rubber mounts and of course the Tie Rod end and ball joints of A-Arms developing the play, over the years.

I read several posts hear about guys running this PS rack with out the P for years without any issues. Guess you never hear about the ones that failed and went off a cliff or something :+) But like you're saying, safety inspection are always good. Wouldn't just driving revile this play? Like the steering wheel jiggle without turning the wheels. Without the PS I feel like I'm more aware of any wheel giggle cause it's not being masked by the PS.

Would be great if someone could also say what they looped and fluids used for those that have deleted PS that way.

Also you may consider loosening all U-Joints and rack and pull it tight from top to bottom and retighten in that order. I would think that the vertical play in the splined clamping bolt could slide within it's pocket creating accumulated slack and play. (in addition to metal wear)

[earlr85944]

I run my early 85 without the belt, I prefer the tighter steering.
My late 85 has a manual rack( funny it's the one that needs new u-joints) Ill be replacing them very soon.
Jiven Jim, yes you would feel the play in the steering wheel if the joints are worn as you said. On the second point, readjusting the splines does not help because the wear occurs horizontally in the joint not vertically. I didnt think of making it a closed loop for lubrication, I will add it.
The shafts are the same thickness, and u-joints and the same as is the spline. The difference is the length.

Actually when doing the conversion you could replace the shaft with some round stock and modify it for use for the manual rack using the orig u-joints. Again for people with the skill andaccess to the correct toys.
just: key\pin\weld or whatever floats your boat to use for the manual rack.

[scheistermeiste]

there are a ton of people with 2nd gen Rx7s doing this. i was one of them when my motor ran. we would remove all the hoses, pump, all that good stuff. then turn the wheel lock to lock to make sure we got all of the fluid out. then we add just a little bit of fluid and plug the holes with npt plugs. the most important part was making sure you didnt have too much fluid left in it. if you did and turned the wheel to lock on the side of the plugs you could build up enough pressure to shoot a plug out and it sounded like a shotgun going off.

i ran mine like that for over a year and so have many others... but i dont know the differences in the rx7 and 944 racks.

[earlr85944]

excellent idea! perhaps an expansion fitting on one end would help.

[pokey]

Just run hoses straight to the resevoir. That way you can check to be sure there is fluid without pulling every thing apart.

[Zero10]

The U-joints wearing out is a compound problem.
First, they are 20 years old, and second, due to the differing ratio of the power rack versus the manual rack, additional stress is placed on the U-joints when used in a powerless rack configuration versus a true manual rack.
You definately can feel them wearing out. It feels exactly the same as bad tie rod ends. In fact, it took me some time to pin it down as the U-joints, and not the tie rods.

[scheistermeiste]

Originally posted by earlr85944
excellent idea! perhaps an expansion fitting on one end would help.

i forgot a part.
actually a few of them would make a new hose and fill it with some fluid (dont know ammount) and loop it. i dont know how well it worked, but in theory (if i remember correctly) the pressure when turning in one direction would act similar to the actual pump. dont know how well it worked though as i just capped mine.

[tifosiman]

To do it right you really need to get a manual rack. IMHO there is no comparison between a PS rack that has been disabled and a real manual rack.