69 ZF Steering gear adjustment

[caproader]

So here's the problem: When I drive the '69 at speed on the highway the steering feed back is somewhere between vague and reminiscent of my father's 68 Chevrolet.

The ball joints and tie rod ends are new. The bearings are adjusted (twice). The alignment was done 1500 miles ago.

So I got out the manual to look at any adjustment procedure for the ZF steering rack. The manual talks about taking the cover off ( Did that) and using a weird looking torque wrench to measure the drag. Then it talked about moving the multi toothed adjustment wheel counter clock wise three clicks (notches).

So here are my questons: Can I tighten up the steering by turning the adjustment toothed wheel? If so, which direction when I am lying on my back looking up at the box. How many tooth clicks will tighten it up enough to feel a difference. Can I go too far? If so, what happens then?

Thanks for the help.

John, loyal dues paying member #322
73 sporto S and 69 912

[edmayo]

Hi John, when you did the restoration on this car did you replace the rubber steering coupler between the steering shaft and the rack? I see those couplers bad more than I've seen a rack that needs to be adjusted.

[caproader]

Ed,

Always a pleasure to hear from you. If you mean part # 901.347.201.02, I am afraid that I did not replace it. Looking at the example that I have on the bench from a parted out car, I can see how the rubber can deteriorate.

Can I change the rubber doughnut out without removing the rack, or do I need to drop the steering rack? Or can I dismantle one of the universal joints in the steering column shaft to get the rubber doughnut out? I would like to be able to do this without needing an alignment when I am finished.

Thanks for the help.

John

[66S]

Check the rubber bushings at the inboard ends of the tie rods, they get pounded out. The simplified [1970 on?] rack and pinion has shims under the center cover that adjust the gear mesh. Make sure the rack center point matches the car's actual straight ahead wheel position. The gear mesh gets tighter at the center position and a little looser when not in the center position. I think the torque value for testing applies to the center position only.

[caproader]

66S

Thanks for the reply. Looks like winter storage may come a bit early here in Ohio so I can get started on this project. Who would have thought that Winter storage would start before the end of the World Series?

Thanks again for your thoughts. I'll give it a look when I get the car in the air.

John

[edmayo]

Hello again John, good point from 66S, so check those first, if okay and you need to do the steering coupler you won't need to remove the rack. You should be able to disconnect the steering shaft at the first u-joint up from the rack. Once you get that separated remove the two allen bolts from the support bushing and remove the plastic dust cover. Now you can bend back the lock tabs and remove the two 13mm hex bolts attaching the coupler to the steering rack pinion. Once you pull out that assembly (steering shaft and coupler) you will then unbolt the coupler from the steering shaft. (before you separate the u-joint paint mark it for reassembly position) Reassembly is of course, the reverse of disassembly, but you already knew that!

[caproader]

Ed,

I ordered the rubber coupling today from Margo at Porsche of the Village. As you suggested, I figured that I would need to witness mark all the steering shaft connections. In addition, it seems logical to do this with front wheels on the ground and steering lock engaged to keep things from moving unnecessarily. After 40 years, it certainly can not do any harm to replace the coupling. The extra 69 box that I have from a previous parts car certainly looks well worn. So I can imgaine what the one in the 912 looks like.

And I will also check the tie rod ends.

Thanks again for your great advice and helpfulness.

John, #322

[haul]

to pick this issue up again:
Steering coupling rubber....

Is there anywhere an instruction for the visual guys?

Is it possible just to loosen the below bolts, then the bushing from
above and just swing the complete steering shaft in order to unfasten the underside bolts?