Tire Pressure question and Steering Shaft issue

[NA5KAR]

Making slow but steady progress on my build. I have a couple of questions. The first is easy. I need to know the correct air pressure for my tires. I have the Halibrand 17” rims with Nitto 245/45ZR17 Front and 315/35ZR17 Rear. On the sidewall, it says Max Press 50 PSI. I don’t want to go that high.

Second question is a bit more challenging. It has to do with the steering wheel distance from the dashboard. I did a walk around video, and someone commented that the steering wheel needs to be much closer to the dashboard. I tried to hammer (rubber mallet) the upper steering shaft further into the lower shaft. It stopped about 1.75” short of where I think it should go if I want the steering wheel Boss to be .25” away from the dashboard. Originally, I followed the Assembly Manual exactly. The text is:

Turn the steering shaft so the recessed bosses for the spring washers are facing up and set the washers in place.
Then tap the upper shaft down until the upper clip just disappears into the lower shaft.

When I follow the instructions, the end of the upper shaft (where the steering wheel attaches) is 4.375” away from the dashboard face. In the 3rd picture below, the upper shaft measurement (4.875”) was taken where the whole outermost ‘recessed boss for the spring washer’ is just outside of the lower shaft. The recessed boss is .5” diameter. That’s where I got the 4.375” measurement.

So, before I start grinding the upper shaft so it’s thinner, or cutting off a couple inches from the bottom of it, does anyone have a guide for;

1. how much of the upper shaft should be protruding from the dashboard?
2. where the bottom of the steering wheel Boss should be in relation to the dashboard face?
3. how to correctly trim the upper shaft to more easily go deeper into the lower shaft (if necessary)?

Thanks for any guidance. Dan

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[egchewy79]

22-24psi for tires.
For the steering wheel, both spring washers should be in the lower shaft. No cutting or trimming should be necessary of the upper shaft. Get your seat where you want it. Steering wheel should hit your wrist with your arms fully extended while seated. You don't want it too close to the dash as you lose clearance against the DS door the closer you get to the dash. You might need to sand the upper shaft down a bit of there's a tight fit with the spring washers in place.

[NA5KAR]

22-24psi for tires.
For the steering wheel, both spring washers should be in the lower shaft. No cutting or trimming should be necessary of the upper shaft. Get your seat where you want it. Steering wheel should hit your wrist with your arms fully extended while seated. You don't want it too close to the dash as you lose clearance against the DS door the closer you get to the dash. You might need to sand the upper shaft down a bit of there's a tight fit with the spring washers in place.

Thanks for the info egchewy79. Earlier this morning, my son and I put the drivers seat in the car and did the 'arm length' test with the steering wheel. The upper shaft was into the lower shaft so that the outermost spring washer was just inside the lower shaft. This was what the manual described. We realized that the wheel had to be significantly closer to the dashboard. We measured carefully and made a mark on the upper shaft where it should be near the face of the dashboard. It was almost 3" worth of movement needed. Unfortunately, it only moved an inch and a half (with the rubber mallet) before it stopped. I can live with that, but there is more visible steering shaft than I was expecting. Is this normal?

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[edwardb]

Be careful hammering on those parts. Multiple posts were guys got them installed and couldn't get them back out. To the point of having to replace in a couple posts I remember. Should go in with a bit of effort. But not forced. Maintenance issue plus a safety issue. That shaft is supposed to collapse in case of an accident. Don't know how often that happens (hopefully never...) or how effective it is. But I would never want to disable something that's intended for my personal safety.

I suspect that so many put in the Russ Thompson turn signal piece that the actual distance is never measured or even attempted to be adjusted. That assembly basically defines where the steering wheel is going to end up. I haven't done the wrist test cited. But with the RT piece I've installed on every Roadster build, the wheel felt at the right position. Not suggesting you have to get one. That's your choice. But maybe someone could post the measurements from that installation. I don't have a Roadster here at the time to provide anything myself.

[TriPower]

I started at 20 psi in my first tires. My current tires are Nitto NT05. My track time has found that 18 works best to me. So I suggest you start at 20 to 22 psi and if you intend to track the car then consider dropping it to 18psi,

Lee

[65 Cobra Dude]

One stupid question for you. There is a collar on the upper shaft that has (2) 1/8” grub screws holding it to the shaft. Are you sure those grubs are loose and it slides on the shaft? I’ve been doing this a while and never had to cut steering shaft on any FFR models.

Henry

[CraigS]

One stupid question for you. There is a collar on the upper shaft that has (2) 1/8” grub screws holding it to the shaft. Are you sure those grubs are loose and it slides on the shaft? I’ve been doing this a while and never had to cut steering shaft on any FFR models.

Henry

Bingo!

[egchewy79]

my upper shaft was tight as well and needed to tap it in gently with a plastic dead blow hammer. try sanding the upper shaft a bit w/ some fine grit paper or emery cloth and see if it slides in easier. the set (grub?) screw is also a good place to look.

[NA5KAR]

One stupid question for you. There is a collar on the upper shaft that has (2) 1/8” grub screws holding it to the shaft. Are you sure those grubs are loose and it slides on the shaft? I’ve been doing this a while and never had to cut steering shaft on any FFR models.

Henry

If you are talking about the set screws in the Pillow Block Bearing, yes, I removed them before tapping on the upper shaft. That's a great question though. I can't imagine that it's this hard to get this right. I'm wondering if I got an upper shaft from another model (33) that may be longer than the Roadster. I'm going to Google images of Cobra steering wheels and see what pops up. If any of you out there have a picture of a side view of your steering wheel placement in proximity to the dashboard, I would be grateful to see them. Thanks.

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[NA5KAR]

Be careful hammering on those parts. Multiple posts were guys got them installed and couldn't get them back out. To the point of having to replace in a couple posts I remember. Should go in with a bit of effort. But not forced. Maintenance issue plus a safety issue. That shaft is supposed to collapse in case of an accident. Don't know how often that happens (hopefully never...) or how effective it is. But I would never want to disable something that's intended for my personal safety.

I suspect that so many put in the Russ Thompson turn signal piece that the actual distance is never measured or even attempted to be adjusted. That assembly basically defines where the steering wheel is going to end up. I haven't done the wrist test cited. But with the RT piece I've installed on every Roadster build, the wheel felt at the right position. Not suggesting you have to get one. That's your choice. But maybe someone could post the measurements from that installation. I don't have a Roadster here at the time to provide anything myself.

I appreciate your insight. I was aware that the upper shaft acts as a collapsible safety feature. I wont do anything to jeopardize that. I'm just hoping that I can get some good dimensions for the installation to see what I'm doing wrong. Thanks so much.
Dan

[D Stand]

Here are a few pics of mine in its final location. I had your same problem at first. I did not need to sand, cut, or hammer anything to get it right. Things I did to resolve are:
1. Remove wafer washers to remove added friction for test fitting.
2. Once I removed washers I found that there was still some restriction.
3. My upper shaft had some surface rust on it so I just took some green Scotch Brite pad to it.
4. Step 3 allowed for the shaft to smoothly go all the way in.
5. To help prevent further rust I wiped the upper shaft down with a lite coat of Tri-flow but anything with Teflon in it would do.
6. Put the washers back in and it slides great with nice resistance.

You want the shaft to be able to got further in than the dash for safety. If you do get in a reck you want the wheel to collapse. If you have to hammer it in at first this won’t be possible.

Mine did not have this issue but make sure the shaft is not interfering with the 3/4” horizontal bar in front of the upper bearing. If it is you might need to space the bearing up with washers per the manual.

Hope this helps..

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[Norm B]

I think I see your problem. Although it is not in focus in the last picture you posted, it looks like the inside of your lower shaft is very rusted. You will need to clean that out and put some rust preventing lubricant in there to prevent the shafts from rust welding together in the future.
While you are cleaning it check that the opening isn’t beveled in like mine was. It had a little lip all the way around the inside like you get when you cut pipe with a pipe cutter.
I set my steering distance as shown in the second picture. This position allows my left hand, while gripping the wheel, to pass unrestricted past the door. I can also reach the horn button with the middle finger on my right hand without taking my hand off the wheel. This has the added benefit of having the middle finger properly positioned for further communication if required.

HTH

Norm

[phileas_fogg]

Since we're talking about rust, be aware that the upper steering shaft will rust over if you don't paint it. BUT, if you paint too much of the shaft, it won't go through the pillow block bearing as far as it should, AND will seize to that bearing. So only paint about from about 1/4" into the hub to about 1/2"-1" past the dash. You should have bare metal going through the pillow block bearing.

If you do paint too much of the upper shaft and it locks up in the pillow block bearing, you can remove the hub bolt & replace it with several inches of all thread. Then use some rope & a hammer to make what climbers call a "funkness device". This allows you to jerk/yank the shaft loose.


John

https://live.staticflickr.com/65535/50849576948_f48f324904_4k.jpg (https://flic.kr/p/2ktpnDW)IMG_6318 (https://flic.kr/p/2ktpnDW) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr

https://live.staticflickr.com/65535/50850391962_35737d6799_4k.jpg (https://flic.kr/p/2kttxVU)IMG_6322 (https://flic.kr/p/2kttxVU) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr

[JohnK]

Since we're talking about rust, be aware that the upper steering shaft will rust over if you don't paint it. BUT, if you paint too much of the shaft, it won't go through the pillow block bearing as far as it should, AND will seize to that bearing. So only paint about from about 1/4" into the hub to about 1/2"-1" past the dash. You should have bare metal going through the pillow block bearing.

What do you think about using Sharkhide on the upper steering shaft to protect it from rusting without adding the thickness of paint to it?

[phileas_fogg]

I don't know anything about Sharkhide, as I've never used it. I do know that the Rustoleum Hammertone Silver I used was only a handful of mils thick, and it locked up TIGHT.

You can always try it, and if the upper shaft doesn't slip through the pillow block bearing by hand, remove the Sharkhide with acetone & sanding.


John

[NA5KAR]

Huge thanks to all of you, but most recently, D Stand, Norm B, and phileas_fogg. I think I know where I might have had an issue. I'll check it in the next day or two when I have time to get into the garage. A few weeks ago, I noticed surface rust on the upper shaft. After scuffing the upper shaft, I taped off the dash and everything surrounding it and sprayed a Rustoleum clear on the shaft. That has to be part of the issue of the shaft not advancing through the pillow block bearing. Thank you phileas_fogg for this insight. Can't wait to test that theory and the other suggestions. My only question/confusion is this; The manual shows the upper shaft going into the lower shaft 'only' just past the second spring washer. If I advance the upper shaft a couple of inches further than the manual shows into the lower shaft does that screw up any functionality or safety. That's really my only concern. Thanks again guys. This forum is amazing.

[nucjd19]

What do you think about using Sharkhide on the upper steering shaft to protect it from rusting without adding the thickness of paint to it?

I did a lite sanding on mine and covered it in shark Hide. I am hoping that will keep the shine on.

[Norm B]

If you push the upper shaft into the lower shaft further than the manual instructs you could have an interference issue with the steering wheel and the door/body. Once the body is on and your seat installed adjust as best you can to be comfortable.

Norm

[NA5KAR]

If you push the upper shaft into the lower shaft further than the manual instructs you could have an interference issue with the steering wheel and the door/body. Once the body is on and your seat installed adjust as best you can to be comfortable.

Norm

Thanks Norm. That's what I'll do.

[J R Jones]

Coatings on close tolerance metal to metal is problematic and any coating will likely fail to some degree. When engineering parts to fit together the coating is part of the dimension calculation, including EDP or plating.
In similar circumstances I treat the bare metal with POR Metal prep which is a phosphoric acid based etch which results in good rust removal and protection. Then I coat the part with a non-evaporating lube like Fluid Film paste, the parts are lubricated and protected without challenging dimensions.
jim

[NA5KAR]

Thanks Jim. Good info

Dan

[Norm B]

I'm a bit of a red neck and have been known to use gun oil in spots like this. It is designed to prevent corrosion and not evaporate and get sticky. Whatever you do, DO NOT USE WD40 or similar products. They will glue the parts together over time.

Norm

[NA5KAR]

I'm a bit of a red neck and have been known to use gun oil in spots like this. It is designed to prevent corrosion and not evaporate and get sticky. Whatever you do, DO NOT USE WD40 or similar products. They will glue the parts together over time.

Norm

Got it Norm. Thanks for the heads up