Steering Shaft Adaptor Failure

[gwayne]

Guys: My steering shaft adaptor failed yesterday allowing the steering wheel to turn freely in my hands. Fortunately, I was driving slowly when this occurred, otherwise this could have been fatal. As I look at the manual, it looks to me like the rack end of the adapter is splined but the steering column side is just held in place with a single set screw? That is where the failure occurred. Is that set screw really the only thing holding that shaft together or should it be spot welded to make it a more permanent attachment? This is pretty critical so I would like your best thoughts on this.

Thank you. gw

145035

[CDXXVII]

Can you post photos of the failed part. I’m pretty sure the part is “keyed” and the set screw just keeps it from coming apart.

Found these photos. I can't imagine how yours failed.

145040

145041

[FFinisher]

Can you post photos of the failed part. I’m pretty sure the part is “keyed” and the set screw just keeps it from coming apart.

Found these photos. I can't imagine how yours failed.

145040

145041

I have never see one come apart, usually you have to remove the steering rack to get enough room to get them apart.

I too would be interested in pictures.

[DSR-3]

If what is shown here is accurate, depending on a set screw for this application is totally unsafe, and downright scary.
Any critical, or even important coupling like this needs to be thu-bolted (and should be safety wired).
I'm surprised to say the least seeing this on ANY car, let alone one that get's so much attention from builders/drivers on assembly.

[silver_pilate]

It's no different than the input shaft on the steering rack and the coupler that joins to it. Those parts are not through bolted, even on many OEM vehicles; they are splined and held with a set screw into a divot. The adapter in question is keyed and secured with the set screw. If the steering column/shaft is set up correctly it will not be able to come apart.because there is no room to pull it apart.

[DSR-3]

I've seen pinch bolts on splined steering couplings, but never a set screw (until the picture above?) I didn't notice that this coupling is keyed, but set screws are still not for cool to me.
Every designer and builder should read Build to Win.

[jcrumpley]

I just looked closely at my car. I can't see any way this could come apart even if the set screw was missing. Either the bearing at the firewall would have to fail in addition to the set screw being out, or the steering rack would have to move out of the mounts. Are you sure you don't have a defective part?

[BradCraig]

Everything on mine was splined or keyed, no way for that to happen. Maybe post some add'l pics of the shaft and socket? Scary as heck though!

[GTBradley]

Guys: My steering shaft adaptor failed yesterday allowing the steering wheel to turn freely in my hands. Fortunately, I was driving slowly when this occurred, otherwise this could have been fatal. As I look at the manual, it looks to me like the rack end of the adapter is splined but the steering column side is just held in place with a single set screw? That is where the failure occurred. Is that set screw really the only thing holding that shaft together or should it be spot welded to make it a more permanent attachment? This is pretty critical so I would like your best thoughts on this.

Thank you. gw

145035

Glad you and your car are safe.

Just to be sure, what car/model is this you're talking about? Have you checked the bearing at the firewall? The set screws are to keep things snug but the connection on one end is splined and keyed on the other and if the bearing at the fire wall is secure then the shaft shouldn't be able to move in or out. Power steering, as I recall, requires a different adapter than manual steering, so it would be good to know that. The picture you have there is from the manual, have you got pictures you could share of your steering issue?

[MSumners]

Regardless of the mechanism of error obviously this would be important to follow to completion to prevent anyone else from experiencing the same issue.
Any other images available?

[PG_Cobra]

I ran into this problem twice although it didn't progress to the point of failure. Both couplings were Flaming River.

The first was a splined coupling with set screw. When torqued up it would appear to be good but as there was no clamping force on the splines it soon worked loose giving free play and a knock-knock when the wheel was wobbled.

The second was their pinch-bolt coupler. The pinch bolt sits in the pinion groove but bottoms out and doesn't clamp on the splines. They have a set screw for the splines which fails the same way as the 1st coupling.

I went with a Unisteer pinch-bolt coupling. The pinch-bolt works correctly and clamps the splines. No set screw!

[RoadRacer]

gwayne, please come back to this thread and give more details! Not doubting you had trouble but I can't see how it can come apart.

[glastron351]

Yes .. updates please...If it's a part mismatch it would be nice to know....as others have said the set screw should only prevent the shafts from pulling apart, not one from turning inside the other....again updates or pics?

[Lickity-Split]

Can you please provide a pic of the inside of the female connecting part that was turning (spinning) on the splined steering rack input shaft?

Since this could literally be a life or death issue, we really want to know exactly how the failure occurred so we can double check our own parts.

Thank you.

[Jeff Kleiner]

Yes .. updates please...If it's a part mismatch it would be nice to know....

The original poster put this out on both forums and hasn’t logged back into either one since. Kinda’ makes you wonder...:confused:

Jeff