1968 DeVille Convertible - Restoration

[Highwayman68]

That is an interesting plan, however I would suggest that they first run a balance test with just the adapter that you made to verify that it will not cause an imbalance that would be added to the wheel when the wheel is being balanced.

[DeVille68]

Exactly! :-)
That is what I also told em. They then said, well, then we just mount the the brake drum and the wheel and balance them together.  Also not too bad, but I won't be able to rotate the wheel in the future unless I balance them again.

So my four steps are:
1) balance my tool
2) balance the rear brake drum by them self
3) balance the tire
4) wheel and brake drum - just to be curious. (no actual balancing just measuring)

Hope I can do this next week.

[savemy67]

Hello Nicolas,

The interior looks great.  From the photos, the wood and the green finish are a very nice contrast.

If you plan on driving in cold weather, the expense of a new heat riser valve may be justified.  I do not plan to do much cold weather driving so I replaced my heat riser with a spacer I made.

Although it won't hurt, your efforts at balancing your drums/wheels/tires may not eliminate the annoying vibrations.  Occasionally, you may see some brake drums that have small, rectangular pieces of steel spot welded to the drum.  This may be the factory attempt at balancing the drum.  There are many variables to consider when trying to obtain perfect concentricity of the front wheel/tire assemblies:  wheel bearings, spindle, wheel bearing adjustment, position of nut and cotter pin, brake drum, wheel, condition of center hole in wheel, condition of lug nuts and holes, tire, and inflation pressure, not to mention the condition of the steering and suspension components and alignment.

The adapter plate is a good idea.  If the shop insists on balancing the drum/hub/wheel as an assembly, you can always match mark the wheel to a stud so that you can replace the wheel in the same position relative to the hub.  Keep up the good work.

Christopher Winter

[V63]

2) As I mentioned earlier, I installed the braces under the hood connecting the two fenders. Now I have driven some 400 miles more on highway and in the mountains. These braces really make a difference. I would recommend to install these if you drive on twisty roads.

Interesting, Only on convertible models . Cadillac omitted those braces that v out from the firewall to each fender well. If a convertible was ordered with automatic level control...you got one brace because the ALC pump hangs from it. Snap Plugs were placed into the fender well holes. (See image)

[DeVille68]

Hi V63

Yes you are right.

Since I do a lot of twisting mountain road driving, I thought I put those braces on. And they do make a difference. Maybe not noticeable when driving mainly on flat roads.

[DeVille68]

Success! No vibrations anymore! 

Every wheel & tire needed about 30-60 gr of weight (on both sides). Some where even better without the weights at all. So now I had em balanced to 0/0 - very nice. When I then added the brake drum the balancing machine showed that some weight was needed. But since the shop operator had never put a tire with a brake drum on the machine he couldn't really tell if this result was normal or not. So we just let it be and well it turned out to be good without additional balancing of the brake drum.

Machine was not able to balance my adapter plate - too little mass and hence force. Also the brake drums where not enough to be balanced on their own. Maybe not the best machine I had access to. Balancing with or without the adapter plate really made a difference of about 5 to 10 gr on each side.
Well now, you can argue which measurement is better....in my opinion balancing with the plate is better.....


Important note:
- Try to find those special weights with the long attaching piece such that they allow the chrome wheel cover to be mounted.
- I did not had those. So I just used regular weights on the inside of the wheel.
- On the outside I attached special flat weights (standard weights today?) with adhesive on the second stepped surface
- Now the weights are not in the same plane, make sure you can set this in your machine.
- Make sure you have your tires properly inflated.

Here is a picture at the shop with tires and balancing machine.
I painted my wheels and drum about 16 months ago - paint still hold up great! I painted them with POR15.
Next, I will measure if the tires are really round - I am just curious. And I need to increase positive caster, to give me more return force leaving a curve.

Best regards,
Nicolas

[DeVille68]

I am ready for a proper engine tune up - my timing light with advance and vacuum gauge just arrived. Also tachometer and dwell available. I have a HEI system installed.

--> Could anyone provide me with a pdf section of the shop manual on how to tune a cadillac Hei System?
--> How can I determine from which model or year my HEI system is?

(in the 68 shop manual this is within section 6 - engine electrical)

Thanks a lot!
Best regards,
Nicolas

[dwbic]

Hi Nicolas,

I don't have a Shop Manual that addresses HEI system, but, if you haven't already seen it, maybe this thread will help.

http://www.modifiedcadillac.org/forum/index.php?topic=7202.0

Best regards,
Don

[DeVille68]

Thanks Don. Well before I check the timing I need to find top dead center. I noticed that someone had but the pulley 180° wrong on the crank. The notch on the pulley is completely off. But in order to be able to find TDC I need to be able to turn the engine precisely.
I tried with the starter motor, but it is not accurate enough.
There is a thread in the middle of the crank pulley, it should be a 9/16 fine
I hope I can put a screw and ratchet on it and turn the engine this way.

I just read an interesting book about the history of Cadillac from 46 up to 2004. It is quite interesting, no technical details but it explains the management decisions and the consequences thereof. The book is called: "The Cadillac Story - The postwar years" from Thomas E. Bonsall

[DeVille68]

I am also in the middle of restoring the A/C system. I had to buy a transducer because mine was missing. Now I also removed the A/C dash unit because vacuum was leaking from the unit. It is quite difficult to get the unit out. There is very little room. To most problematic was removing the wire terminal from the unit - I had to use a lot of force.

The rotary vacuum valve was full of crud and dirt had cut small grooves into the surface. See the pictures below.
Otherwise the unit looked good. I removed also the lens to clean it out. Re-greased the joint of the lever mechanism.

The last step I need to do is to put a tap and screw into the rotary valve - since I had to drill the rivet out to be able to separate the valve.

[cadillacmike68]

Recently, I also added my kick-down switch that I got from Tim.
Solenoid of the transmission does work, so it was just a matter of bolting it in. The shop manual has a nice explanation how to mount it such that the kick down is activated at about 60% of throttle.
The pictures below show some more details of the setup.

Regards,
Nicolas

P.S: I think my throttle return spring is wrong. Should it be shorter and attached to the tab of the kick-down & dash-pot plate?
Where can I get that spring? Are the different stiffnesses?

Nicolas,

Nice work. You have done a Superb job with the car. The green is nice and the wood is gorgeous. The tires - sometimes the diamondbacks (and coopers are said to be worse) sometimes don't balance correctly. It also could be bent wheels. My tires each only take about 20g weight in one place to balance.

Now a question from earlier:


On this particular post (from 2014) I notice you have that crazy actuator arm for the kick down switch installed in pic 2. It looks about right, the shop manual is not very helpful on this. There was only one spring.

How do you keep that from falling off the square shaft that is sits on? Mine keeps popping off and it is a real PITA getting it back on.  Right now its sitting on the intake manifold...

[DeVille68]

Thanks for your compliments!
Well, its a "rolling restoration" - already four years!

Regarding the kick down switch:
Yes, there is nothing holding the arm to the square shaft.

Although your throttle linkage should have a bracket with a hole in it. The square shaft should go partially in this bracket, hence the arm cannot slip from the shaft.
See the picture attached.

Best regards

[DeVille68]

About a year ago I installed my vacuum trunk release mechanism. I had an extra vacuum tank, which should be mounted inside the driver side fender. But the valve was damaged, it could not hold vacuum anymore. So I did not install the tank yet - the trunk release was only operational when the engine was running...

So now came the time to restore the vacuum tank!

• I did cut the top of the can with a small cut of wheel.
• The valve is riveted to the cap, so drill out the rivet. Picture 1 shows the pieces of the valve
•   You may notice that the red membrane is damaged at the center. It was not able to seal in the middle
•   The second picture shows the casting where I had cut a thread inside.
• The third picture show the idea: Instead of riveting I use a screw from the bottom up though the middle vacuum terminal.
• Obviously I need a path for the vacuum, so I drilled a hole into the screw. The middle vacuum stud has now a path though the screw. The fourth picture shows the final assembly
•   I cut a new membrane out of an old bicycle tube.
•   Picture five show the full assembly of the restored vacuum valve.
•   Picture six show the can and cap all blasted and ready for soldering
•   Finished soldering and pressure and vacuum tested the valve, shown in picture seven. The middle port should hold vacuum. The offset port is for the engine vacuum connection. It should allow pulling air out of the can but let no air in.  I used a hand vacuum gun to test both functions. The valve now hold easily 1.5 bar of air pressure and at least 0,7 inHg vacuum.
•   Picture eight: Ready for paint, I used POR 15 semi gloss black
•   Picture nine: Finished restored vacuum tank!
•   Next step: install the can into the driver side fender. In picture nine you can identify the two different brackets for the can for A/C (on the firewall) and the can within the fender.

I hope this little instruction helps you restoring your vacuum tank too!

Best regards,
Nicolas

[savemy67]

Hello Nicolas,

Well done!  How did you hold the vacuum tank when you cut off the end of the tank with a cut-off wheel?

Christopher Winter

[DeVille68]

well, by hand!  It was just a very small blade, about an inch in diameter.

[dwbic]

Thanks Don. Well before I check the timing I need to find top dead center. I noticed that someone had but the pulley 180° wrong on the crank. The notch on the pulley is completely off. But in order to be able to find TDC I need to be able to turn the engine precisely.
I tried with the starter motor, but it is not accurate enough.
There is a thread in the middle of the crank pulley, it should be a 9/16 fine
I hope I can put a screw and ratchet on it and turn the engine this way.

Hi Nicolas,
Regarding turning the engine precisely, are you familiar with a flywheel wrench? 

They work great for turning the engine right where you want it. 
Best regards,
Don

[DeVille68]

Hi Don

No, never heard of such a tool before! But could it work with the engine still in the car?

[DeVille68]

Hi guys

I just found a perfect sibling car for my convertible! 
http://www.ebay.com/itm/1968-Cadillac-DeVille-4dr-Sedan-/282252899141?ssPageName=ADME:B:SS:CH:1120

It is a 68 four door in silverpine green and dark green interior. Just like mine.
But it has cruise control and a remote trunk lock mechanism!

I wish I had the money and space to put those side by side! 

[DeVille68]

A few days ago I finally installed the vacuum thermo switch that I had laying around for about two years now. First I had to remove the distributor because the wrench was too big and it was easier to work with a bit more space too.
I took the manifold vacuum from the secondary lock out diaphragm, according to the shop manual it has manifold vacuum. I just put a Y-connector into the line and routed it to the thermo switch. The other connection is just the "normal" distributor vacuum port, which has "ported" vacuum.
Let's see in spring if this works as intended.


Second major work:
I removed the wiper dash unit, because I "fried" the lens about a year ago when I removed the wood veneer from the dash. In the first picture you can sport the burned part of the lens.
The unit is held together by three rivets, which I drilled out.
The inside is quite simple (I did not expect that). You basically just move a "cart" over a connecting plate below. The positions for low, middle and high are located by three little slots within the top part of the unit. The cart has two springs and two small balls, these balls push into these slots as you move the lever letting you know where the positions are.
The other side of the cart makes connection to electrical part of the "switch". As you move the cart it connects directly to the unit or via the resistor on the back of the unit.

The pieces where just a bit greasy but still intact. I will insert a small flat washer into the hole of the two spring to give them a bit more force. Because sometimes I missed the actual positions for low or middle.

Then I started sanding and polishing the lens. Basically it is quite simple - I started with 5000 grid paper, but soon switched to 2000. And then to 1500 and finally to 1000. Only 1000 removed (almost) all the burned traces. Once I was happy with the result, I switched to 5000 and sanded the lens smooth again.

After that I used a polishing rag and some compound normally for the car paint. I came out great! I can't believe that I saved my lens! I though I had to throw it away or fabricate something....



1. Picture: You can sport the burned parts of the lens
2. Picture: Disassembled
3. Picture: Cart with the two balls that slide along the top cover, as visible in picture 2
4. Picture: Washer wheel. It grounds when depressing.
5. Picture: There are two "springs" below it, such that the "wheel" returns and such that you have to hold it down to activate the pump.
6. Picture: Underside of the cart with the two dimples that slide along the connector
7. Picture: finished and polished lens!
8. Picture: another angle.

9. Picture: Vacuum thermo switch below the distributor.
10. Picture: Y-vacuum connection at the carb for the manifold vacuum source.


Coming up: putting everything together again!

[dwbic]

Hi Don

No, never heard of such a tool before! But could it work with the engine still in the car?

Hi Nicolas,
It will work with the engine in the car - just remove the inspection cover and use it.  They sell for around US$25. 
Best regards,
Don