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Old 11-23-2014   #11
Billy Mild
 
Join Date: Aug 2014
Location: Kansas City, MO
Posts: 838
Default Re: Steering feeling vague

Why must the steering rack be replaced? Can't the tie rods be replaced instead?
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Old 11-23-2014   #12
secondchance
 
Join Date: Aug 2006
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Default Re: Steering feeling vague

Quote:
Originally Posted by Billy Mild View Post
Why must the steering rack be replaced? Can't the tie rods be replaced instead?
I didn't say that it must be replaced. Just that if pinion and rack are worn to a point of being sloppy, I Sam guessing, would have to be replaced.
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Old 11-23-2014   #13
mike100
 
Join Date: Feb 2011
Location: San Marcos CA
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Default Re: Steering feeling vague

I test drove a 92 vette yesterday with 209k miles on it and the chassis and steering felt about the same as my 39k mile car. The interior and typical C4 wear items were another story, but the chassis/suspension and steering would seem to be a strong point on these cars (for street use anyways).
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Old 11-23-2014   #14
Hib Halverson
 
Join Date: Jun 2005
Location: CenCoast California
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Default Re: Steering feeling vague

Quote:
Originally Posted by WVZR-1 View Post
I didn't assume it was for free-play adjustment and referenced the FSM for preload adjustment. 45mm (1.77165) is quite close to the what I measured and I don't believe that I measured quite that so I referenced it to what I felt most might have access to locally or inexpensively.

The physical mounts of the rack to the chassis could also create a similar feel but I would think that more easily checked from underneath under power when checking inner/outer tie rods. A person if they felt an issue when holding the intermediate shaft could of course increase the effort and likely see the rack move if it were a mount issue.

I believe a reasonable number of potential intermediate shaft issues would be found vs. actual steering rack issues, maybe not the bolt at the rack coupling or the bolt at the column coupling but the "rag joint" on higher mile cars.
In previous posts I incorrectly identifed the "rack bearing" adjuster as a "pinion bearing" adjuster. I apologize for that mistake.

I went out to the shop last night and looked at the socket I bought for the lock nut on the rack bearing adjuster. The locknut size is, indeed, 45-mm. The reasons I bought a socket were 1) the nut requires tightening to 55-ft/lbs and lack of space around that nut precludes use of an open-end wrench, pipe wrench or slip-joint plier and 2) the cost of a 45-mm or 1 3/4-in box wrench was far more than a socket. I bought the socket from Amazon.

Someone asked about inner tie rods...

They can be replaced but it requires removal of the rack to do it.

Finally, the ZR-1 steering has no "rag joint". The last Corvette to use one was C3. There is a universial joint just above the steering rack at the end of the intermediate shaft which serves a similar purpose. Obviously, if that u-joint is wearing or has failed, play would develop in the steering.
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Old 11-23-2014   #15
WVZR-1
 
Join Date: Oct 2004
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Default Re: Steering feeling vague

Quote:
Originally Posted by Hib Halverson View Post

They can be replaced but it requires removal of the rack to do it.

Finally, the ZR-1 steering has no "rag joint". The last Corvette to use one was C3. There is a universial joint just above the steering rack at the end of the intermediate shaft which serves a similar purpose. Obviously, if that u-joint is wearing or has failed, play would develop in the steering.
Hib - just because the "rag-joint" isn't directly bolted to the gear box or steering rack doesn't disqualify the use of the term to describe the "coupling" between the two halves of the I/S shaft. That I believe is getting just a bit to damned technical. What would you care to call it?

The later C4 I/S shaft has u-joints top and bottom at the steering rack and the column lower shaft but a "flexible" joint in the center to absorb I would think harmonics.

C4 steering shaft.jpg

When I mentioned "rag joint" I'm referring to the flexible aspect at the joint of the two halves of the I/S shaft. I realized I used "intermediate shaft" for what SPO and GM service calls steering gear coupling but I believe it's generally understood I believe to be "intermediate shaft".

Can your 45mm socket be used in the car?

A replacement I/S would need to be from a '90 - '95 ZR-1 OR a '91+ base C4. The '90 L98 base car is different.

It might be interesting to investigate the replacement of the "rag/flexible" joint with maybe a urethane/poly service part. I've never done it but I know that there's product out there for other applications with a similar coupling.

YUN - It might likely be possible to tighten the two hex nuts/bolts that secure the two halves of the I/S surrounding the "flexible" aspect also. Lot's of wear/tear could maybe loosen them. Shouldn't require much of an effort in an attempt. Pinch bolt @ top, pinch bolt @ rack and the two @ the "flexible" disc.

Last edited by WVZR-1; 11-24-2014 at 02:37 AM.
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Old 11-24-2014   #16
5ABI VT
 
Join Date: Jun 2013
Location: Toronto
Posts: 783
Default Re: Steering feeling vague

I would guess this isn't normal. If I had some slop im certain my front end would be in pieces lol. my 93 has a short ratio rack and I will probably do the same to my 94 with new tie rod parts to ensure everything is sharp.
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Old 11-26-2014   #17
batchman
 
Join Date: Jun 2009
Location: I live at Devens, one run at a time
Posts: 455
Default Re: Steering feeling vague

Quote:
Originally Posted by Hib Halverson View Post
Someone asked about inner tie rods...

They can be replaced but it requires removal of the rack to do it.
It may not work on this particular rack but a friend has a very interesting set of Snap-On inner tie rod tools that make changing them in-car pretty straightforward. Of course the set was pretty spendy.

Quote:
Originally Posted by Hib Halverson View Post
Finally, the ZR-1 steering has no "rag joint". The last Corvette to use one was C3. There is a universial joint just above the steering rack at the end of the intermediate shaft which serves a similar purpose. Obviously, if that u-joint is wearing or has failed, play would develop in the steering.
I beg to differ, at least on our 91 and another ZR-1 parts car that "universal joint" was most certainly a rag joint - rubber & canvas laminated, just like the old days. This was a surprise to me since our 88 z51 car used something more like a hockey puck. I do not know if all other c4s have the hockey puck or just the z51, but I presume the ZR-1 used the rag joint (and the slow rack) to limit twichiness on a car with such a high top speed, as well as improved NVH in its price class.

On our ZR-1, I started out with the collar tying the rag joint to the lower shaft/rack loosening up, and once tightened the rag joint itself exhibits play, or to be kind "slow engagement".

Quote:
Originally Posted by WVZR-1 View Post
It might be interesting to investigate the replacement of the "rag/flexible" joint with maybe a urethane/poly service part. I've never done it but I know that there's product out there for other applications with a similar coupling.
I switched the intermediate medium on a ZR-1 'universal' to the puck from another z51 car (can't interchange the whole joint) and that, coupled with a quick rack and a Turn-One "stock replacement" pump crisped up the steering very nicely. My race class now allows metal bushings so I look forward to mounting the rack with same for yet another notch of crisp.

And for completeness' sake I have had other cars developing dead spots show big improvement using a high-quality synthetic fluid such as Mercon V or Redline Power Steering Fluid. Overheats less too .

Cheers,
- Jeff
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Last edited by batchman; 11-26-2014 at 02:40 PM.
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