SWB Steering column bearing remedies

[Hayden Burvill]

Looking for guidance from SWB experts who have replaced the composite "ring" in the steering column.
This is part # 901.347.793.00 that is sandwiched between two contoured washers and retained by a pair of round wire retaining rings. Item #34 on the illustration.
The composite ring forms the lower mount for the steering column bearing housing (fwd mount) the rear mount being effected by the clamp on the turn signal housing.
We created our own solution out of immediate necessity last week, as the Porsche part is NLA, but I am sure we are not the first to do this and wondered what the general method is, or if there is a general method in the absence of the O.E. part?

Regards

Hayden

[304065]

Hayden- my original's fine but here is a photo if it helps guide the community to helping. . . all the best.

[Hayden Burvill]

John,

Thanks for that photo.
How confident are you that is an original factory part? (or factory replacement part if not an original built part)
We have 3 x '67 and 1 x '66 (304427) in our charge. The '66 and one of the '67's had the composite ring fully degraded, but from the remnants, it looks like it was more like a cork / rubber blend, granulated in texture. Your part by comparison looks more uniform, kind of like a urethane material. I have not disassembled the '67 912, but it is tight (only 36K miles) and the other '67 is in Carmel this week.

This photo is the column from 304427, the washers in the foreground are from a '67S (the car with issue now resolved), the color on there is not rust, but the color of the degraded material, much of which was still grimly adhering to the washers as we removed the parts, but flaked away onto the bench as handled.

Your UJ has obviously been removed at some point (perhaps to replace the ring?), the '66 O.E. hardware was a cross-drilled bolt with castellated nut and split pin.

I am not obsessed with originality but the issue was discovered after a lengthy hunt for a slight steering vibration, worse than that the additional angle that the UJ could achieve once the "ring" had degraded put the joint at a more critical angle, leading to a heavier and inconsistant feeling in the steering...... potentially a safety issue.

If the ring is NLA more of us are going to need to adress this sooner or later.

[304065]

Hayden,

Good eye-- I think the missing paint on the UJ is the best clue that it had been removed at some point.

This photo is actually of a 37,000 mile 1967 912 that I broke for parts. I don't have the '66 handy but I will this weekend, my recollection is that the ring is identical, but I will look.

Of course the factory changed the steering shafts and universal joints in 1967 from pinch type that held a fairly smooth shaft with a roll pin to splined. As you correctly say, the upper screw in a 64-66 has a drilled shaft for a castellated nut and cotter pin. This is how I found things on my '66. Obviously the Factory realized that to safely "pinch" the shaft the screw needed a lot of preload-- so they specified a hexagon-head bolt M 8 X 35 S DIN 931-10K SW 13 PHR- -a 10K property-class, phosphate coated ("phosphatieren").

Now if you look in a later parts book the screw is an 8G, not drilled, and just "verz" or "verzinkt" which is what you see in my photo. I don't think the M8 nylocks are original, however.

I AM obsessed with originality-- where it shows. . . a replacement ring to firm up the steering of the thousands of SWBs out there would seem to comport with your business criteria of not duplicating the work of others while providing an improvement over the original. I'll dig up what I can to help.

[Hayden Burvill]

Thanks John, I appreciate your help on this.

I was kind of hoping that we would discover what others have been doing when faced with this dilemma.
It is easy enough for us the make a run of the parts, we at least have to do so for the column on 304427 in the absence of another choice.

Even better the factory could consider how fundamental this part is to the safe operation of the cars and create new inventory.

If you want to try and pin down the transition date for the change in UJ parts, I can verify across the Vin #'s for the car I can look at. The '67S we fixed has the 10.9 bolts and castellated nuts, not sure on the '67 912.

Regards

Hayden

[Fritter]

Very interesting topic, you have me worrying about my '68 now.

Does this composite spacer prevent fore/aft, left/right movement, or both?

[Hayden Burvill]

Mike,

The spacer prevents the up-down, left-right movement of the column.

Effectively with the spacer completely gone as we discovered on the '66 above - the column is hinging on the clamp at the base of the turn signal / wiper stalk housing.
The two mount positions are spread by about only 4" and the radial clearance is about .150" so the maximum movement is pretty significant. That car arrived on a trailer, not driven since early 80's. So I suspect no one drove it in this condition. The '67S had some of the composite material packed into that area, but not a full compliment and as it crumbled when disassembled it was hard to determine how much clearance was available in that assembly.

I am not sure you need to worry too much about your car, but if your steering wheel seems sloppy and you have inspected the various other causes, then this composite ring could be contributing.

Regards

Hayden

[buddeman]

Here are a few additional photos from my early '67 project car (built Nov '66). Fairly confident it's original, and exactly the same as what John had posted. Material is a soft urethane type with ridges on the top and easily depressable with a fingernail.

Attachment 68948

Attachment 68949

Regards,

Pat