Friday, February 26, 2016

1976 Corvette Steering Column and the "Vega" Wheel
Part Six

I've been rethinking my original plan to use a few parts from my 1976 steering column when I am ready to do the swap. This approach would certainly save me a few bucks, however, it would delay the swap a bit.

Time and money considerations aside, repurposing parts would also leave me with another steering column in pieces, and that may not be the smartest approach. So I've been doing lots of research in order to purchase the parts I am missing in order to have a fully restored 1979 Corvette steering column, and have it ready to do the swap.

Some of the parts I've had to order include the steering column key lock metal plate (photo on right), the upper bearing spring, turn signal cancelling cam and the steering column upper shaft locking ring retainer.

I also found a new turn signal switch (photo below) at Amazon for $21.11 which will supposedly work for my 1979 column.
 

I have not done the math to determine how much I have invested in this project, but my guesstimate is that I should have the 1979 Corvette steering column completely rebuilt for around $400, and that includes the steering wheel. That's a bargain considering that rebuilt OEM columns retail for around a grand!

Since my steering column was abused by previous owners, I've had to smooth out a few areas with files and sanding paper. Case in point is the channel for the upper shaft locking ring retainer.

As the picture shows, the channel varies in width from one side to the other, so the retainer fits very snugly and one way only.




The retainer ring has a right angled edge, and this chamfer locks it in place. The two photos below show the edge that slides into the thinner channel.




I temporarily pressed the locking ring gently into the channel so I would not misplace it. When I have all necessary components to reassemble the column, I will press it in place fully and hope I don't have to remove it again.




One issue that may prove challenging when the time comes to swap the steering columns, is to properly align the shafts, This will be difficult since the shaft alignment markings were erased by the pounding the shafts were subjected to by previous owners.

Anyway, I will deal with that issue when the time comes.

Thanks for reading, and stay tuned for Part Seven.

Tuesday, February 23, 2016

Getting the Rochester Quadrajet Rebuilt

Attempting to properly tune the Edelbrock 1406, so my '76 Corvette would run properly, has proven to be a frustrating and expensive experience, as well as a losing battle.

I had three professional mechanics tinker with it, and it would either run too lean or too rich, and it would bog down in some occasions. Eventually I took matters into my own hands and got it to work significantly better, but no one is reimbursing me the money I wasted having "pros" tune it up.

Alas, the Edelbrock continues to have issues that have made me decide, once and for all, to give up wasting time and money trying to get it to work as advertised and, instead, have the original Rochester Quadrajet professionally rebuilt.








Originally I was going to use a carburetor company located in Daytona, but they are no longer offering carburetor restoration services so I decided to contact All American Carburetors in Jacksonville, Florida and they can do the job for around $200, which is a lot less than what the other company charged.

One change that I will make to the stock configuration is to convert the choke from hot air to electric. I will discuss this with the guys at All American Carburetors when they call me (I just shipped the Q-Jet to them) and see if they offer that conversion, Otherwise, I can buy the kit from the local auto parts store and do it myself.

One of the issues my Quadrajet had was the common, age-related problem of worn out throttle shafts, but All American installs new bushings so that will take care of that issue. They also rebuild carbs using ethanol-resistant parts which include new accelerator pump, needles and seats. In addition to all that, All American also live-tests 4-barrel carbs to ensure proper float setting, accelerator pump function and that hot and cold idle adjustments and mixture screws are properly set.

From talking to All American Carburetors, my Quadrajet will be ultrasonically cleaned, media blasted and then polished. They will also Zinc Dichromate all steel parts to prevent corrosion. So for all practical purposes, it will be (and look) like a brand new carburetor.

The process takes anywhere from 3 to 5 weeks, which is fine since I also decided to have the air cleaner and original fuel lines powder coated. I dropped them off this morning at a shop in Longwood that specializes in the powder coating process for commercial clients but also takes care of automotive enthusiasts. For $100 plus sales tax, my air cleaner, fuel line and a few related small parts will look better than new.

After doing a bit of research online, I decided to have these pieces powder coated with a "Black Pearl" finish, since photos of NCRS quality Corvettes showed that these parts were shiny from the factory, instead of the satin finish they develop after a few decades of use. Besides, I think they will look great with the "Black Pearl" finish I chose, compared to my spray can "resto" a while back.






I will have photos of the finished product in a few weeks, so stay tuned, and thank you for reading.

Saturday, February 20, 2016

1976 Corvette Steering Column and the "Vega" Wheel
Part Five

As I've probably mentioned before, my steering column bearings are shot, so I ordered new ones along with a few other components needed for the restoration of the assembly,

Everyone knows that parts with the Corvette name attached to them cost twice as much as those intended for the rest of the Chevrolet/GM models and, by a fluke really, I came across a kit offered through Amazon.com for the main shaft bearing, including the retainers and clip. The funny thing is that this kit also fits most Jeep and GM vehicles. Long story short, for $23 I thought I'd get one and if it didn't work I would just send it back. Well, it came in yesterday and it works just fine.

Some Corvette vendors get upwards of $70 for just the bearing, so this was a major score, and proof-positive that doing a little bit of research pays off.




Putting the steering column back together is a challenging process so you need to arm yourself with lots of patience. In my case, I've reassembled one component, for example, only to take back apart a few moments later after realizing that I forgot to install something else beforehand. Needless to say, all this "practice" has made me quite good at steering column mechanics.

One thing I did purchase was a set of E-sockets in order to properly fasten the star bolts that secure the lower housing in place. I also used Loctite (red) so they won't vibrate off. As good as I've gotten at steering wheel disassembly/reassembly, I really don't want to take it apart once it's in the car.

Before reinstalling the lower housing, you must install the key release lever (if your column has one). I added a thin layer of grease to portions of the assembly that slide back and forth. The spring has to be compressed a bit so it sits in the right slot so the lever works properly.




I also reinstalled the lower housing bolting plate, which is a little tricky since it will only go in, in a certain way. You have to hook up the right side first and then the plate falls into place. You will still need to be careful when attaching the lower housing so the bolting plate does not fall off the slots. A long and thin phillips screwdriver comes in handy in order to help align and get the first two bolts started. And don't forget the Loctite.

Having that little marking on the plate helped quite a bit during reassembly.





With the lower housing in place, I reinstalled the ignition switch rod. The end of the rod that sits inside the plastic cover will be connected to the actuator rack once the upper housing is reinstalled.



The upper housing snaps back in place once all necessary parts are installed. I used new bearings since the original ones were destroyed. Actually, I would've replaced them even if the original bearings looked okay. I applied plenty of fresh grease, too.




But before the upper housing is reinstalled, I got the plastic ball joint ready (don't forget the horse shoe-shaped spring) and then attached it to the stub shaft. Again, I lubed all components before reassembling them.




Reconnecting the two shafts is pretty straight-forward since the ball joint will go in one way only. I lubed everything so it would operate smoothly. As the photos below show, the ball joint in the stub shaft must be at a 90° angle in order to connect with the main steering shaft. Once connected, you can rotate the stub shaft and the ball joint will be aligned to operate correctly.





At this point you can reinstall the upper housing, but make sure the actuator rack is in place and that the ignition rod under the plastic cover is connected to the actuator rack, so that it moves back and forth when the actuator rack is pulled or pushed. At this point you want to carefully align the upper housing with the lower housing so that the tilt pawls will engage with the cross shaft at the top of the lower housing.

Even though this all sounds complicated, once you are at this point, it all becomes clear and making the upper and lower housings connect is a straight-forward operation.

With both housings aligned, push the tilt lever forward to release the pawls while pushing the upper housing into the lower. It won't take a lot of force and you will hear a "click" once the pawls engage the crossbar. At this point release the tilt lever and that's it. The upper and lower housings are properly connected.




Before moving ahead with the steering column reassembly process, make sure the actuator rack moves freely back and forth and that the ignition rod also moves at the same time. The actuator rack rests on a small flat spring that sits right below it and snaps in place. I lubed all those pieces before assembly.

With the actuator rack in place, you can now install the steering lock pin followed by the sector gear and ignition lock cross shaft. You may need to tap it in place gently with a hammer. When the cross shaft is fully in, you can reinstall the E-clip. Just make sure the sector gear and actuator rack are aligned properly (see 2nd photo below).

 


At this point I installed the sector gear spring and—while making sure both housings were aligned—I tapped in the pivot pins.




Since I wanted to see how the covers would look when assembled, I temporarily installed them and am happy to say I love the way the textured finish looks.





After inspecting everything to make sure I had not forgotten any small parts, I reinstalled the tilt alignment pin, spring and cap.

In order to be able to compress the spring enough, I had to prop the steering column on the floor so I could push the pin, spring and cap comfortably with a #3 phillips screwdriver. When the cap goes in the channel, you can turn it (about a ¼-turn) and it will snap in place. At this point you can release the pressure and it will lock in place. You want to make sure it is properly seated.




And this is what my rebuilt 1979 Corvette steering column looks like, so far. I did temporarily install the telescoping shaft and key in order to keep everything together. I should have another update soon.

Thank you for reading, and stay tuned for Part Six of the series.


Monday, February 15, 2016

UPDATE: Edelbrock 1406 Tuning

So far, upgrading the metering rods from 0.75" x .047" to 0.70" x .047" and the step-up springs from 4" to 5" Hg has made a huge improvement to how the car drives, especially the flat-spots it was suffering from during acceleration from a dead stop as well as at highway speeds between 60 and 70 mph.

As detailed in a previous post, changing the metering rods and step-up springs is a piece of cake, and after doing so, I tuned-up the carb once more and have it idling nicely at 600 rpm at operating temperature (1200 rpm on a cold start).

It does run a little richer with the current set up, but that's okay as long as it's running fine. As a matter of fact I had it out yesterday for a car cruise in Sanford and it ran beautifully. And on the highway it now blows past the previous 60-70 mph flat spot, easily.

I still plan to install .100" primary main jets, up from the original .098" jets. Secondaries will remain the same at .095".

So stay "tuned" for another update soon.