Looking for Quality Carburetor Rebuild for ‘42 Century

[old car fan]

I don't always  agree with Ed, but its never  mechanical. Not many show cars can do that.

[JimH56]

7 hours ago, Grimy said:

I am impelled to comment for the sake of those new to the hobby that to solve the *vast* majority of driveability issues in a 1942 Buick, one does not *need* five-gas analyzers, chassis dyno, and other expensive and sophisticated test equipment.  My good friend @edinmass also known as "Mr. Five Gas" to those who spend any time with him, surely is correct to use his existing sophisticated equipment to simplify diagnosis.  But we mere mortals without such magical resources can properly rely on a diagnostic logic tree and use more primitive equipment and techniques such as vacuum gauges, compression testers, timing lights, capping off vacuum wiper feeds, and visual inspection of distributor advance weights.  So before you google "auto mechanics with 5-gas and dyno and familiar with 1942 Buicks near me" try it the old-fashioned way if you don't have Ed's resources.

 

Further, we in the forums do in fact routinely ask "have you checked this or that" because in this case as in so many others presented here the OP has not explained what diagnostic measures have been employed thus far.

You are all helpful and it is clear that all want to help.

[drhach]

I'm curious why you rebuilt the carbs(s). You mentioned that the issue started after the rebuild. What was going on that required a rebuild? Just curious. 

 

Regards,

Dan 

[JimH56]

It was an ill-considered “cosmetic” decision. Thankfully it’s just a car and just a hobby. It will get fixed.

[drhach]

How about some pictures of the 42? I have a 42 Special. 

[Frank DuVal]

On 10/22/2023 at 9:23 PM, carbking said:

The modern (reap CHEAP) neoprene accelerator pumps can fail in a couple of DAYS if exposed to ethanol diluted fuel. I have opened up customer carburetors with the blue pump, found the blue material at the bottom of the pump well disconnected from the pump stem, and the fuel in the pump well is BLUE!

Hmm, tell me more. I too have issues with the black Neoprene cups, they shrink and don't work after a short while (less than a year), so I started buying the "Viton" cups that are blue in color from a specialty supplier for Rochester H (HV) carburetors. So far they have performed flawlessly for several years now in about a dozen carburetors. Just bought another dozen cups.

[carbking]

Frank - one of the problems with comments concerning fuel on the internet is that the fuel is not a constant. If you have had good luck with the blue skirts in your area, by all means, use them.

 

As a manufacturer of rebuilding kits, I have to be concerned with all fuel, and the only material I have found to always work, is leather.

 

Jon 

[Frank DuVal]

I agree, just have not found leather cups for the Rochester H HV or I would buy them.

 

Where I am there is no ethanol free fuel sold. There is non-ethanol in counties south, so not a given the cars in this area will be running non-ethanol.

[carbking]

Frank - I have never made the leather pumps for the H/HV carbs, as no one has asked for them in the kits we make. I CAN make them, but it is not a matter of making the cup; one has to fabricate the whole lower end of the pump.

 

Jon

[PFitz]

On 10/29/2023 at 7:25 AM, carbking said:

Frank - one of the problems with comments concerning fuel on the internet is that the fuel is not a constant. If you have had good luck with the blue skirts in your area, by all means, use them.

 

As a manufacturer of rebuilding kits, I have to be concerned with all fuel, and the only material I have found to always work, is leather.

 

Jon 

Yup!  I've seen that even if modern materials hold up to today's fuels, what about next year ? I have seen this happen with fuel pump diaphragms, gas tank sealants, and paints that used to be able to withstand gasoline...... until the chemistry changed. And the results of regional differences in gasoline formulation have to be seen to be believed.  It can mean, some customers with no problems, and in other parts of the country customers that after a month of the car sitting unused, the inside of the carb looks like it's coated with dried contact cement with all movable parts stuck in the "it won't run" position. 

 

Paul

[carbking]

Frank

 

You can make the leather cups yourself, but I don't know what you have as far as shop tools to do the rest.

 

To make the cups:

 

(1) Acquire some scrap "crown leather" (find a saddle maker, they should have scraps).

(2) Measure the inside diameter of the bottom third of the pump well.

(3) Measure the thickness of the crown leather you obtained.

(4) Acquire a piece of one inch thick plywood, maybe 6 inches by 6 inches.

(5) Drill a hole through the center of the plywood about .010 (ten thousandths) larger in diameter than the diameter you measured in step 2. Slightly round the top of the hole.

(6) Calculate twice the thickness of the leather, and subtract that from the diameter of the diameter of the hole you drilled in step five.

(7) Machine a piece of brass rod to be a thickness of .010 (ten thousandths) smaller than the dimention calculated in step 6, with a prong on the end the diameter of the pump stem hole.

(8) Slightly round the end of the rod.

(9) Cut a circle of the leather large enough to form the cup with maybe a 1/4 inch to long for the skirt.

(10) Soak the leather in warm water for 30 minutes.

(11) Place the top side of the leather on the top side of the plywood.

(12) Push the cup through using the brass rod.

(13) Let the leather remain in the mold for 24 hours.

(14) Remove the leather from the mold.

(15) Chuck the brass rod and leather in your lathe, and using a tool with a razor blade, cut the proper skirt length.

(16) Advertise, and sell these to the Corvair club members  

 

Jon

 

Edited October 30, 2023 by carbking (see edit history)

[JimH56]

For those of you who provided useful advice — and you all did — and asked for the outcome, this is the update report. While we rebuilt the carburetors (which was good anyway) the root cause culprit turned out NOT to be the electronic ignition (PerTronix II) but, rather and to our surprise, a distributor that was not the correct model number for the vehicle!  The proper distributor was acquired, a new PerTronix II electronic ignition and coil was added, and she now purrs like a happy leopard!

[edinmass]

Jim…….interesting result. You said it was running fine, and then rebuilt carbs for cosmetic reasons. Having the wrong model distributor should have not caused a running problem as described. Most Delco distributors were using one of three or four basic units that were different size. Then specific advance and point plates were added for the application. It’s common to see a model number followed by letters……thus Model 987 A, 987 B, ect. Depending on the Pertronix unit virtually all the differences go out the window because everything is done electronically and it only becomes a switch to fire the coil. Not being familiar with your particular car, can you post photos of both the old and new distributors? I’m still thinking it was the Pertronix unit all along…..for what reason who knows? If you look at my three responses early on they were mostly right on the money……unknown components just tossed in often times during the conversion to 12V or electronic ignition. Is the vacuum advance's still being used? It’s possible a replacement distributor was installed back in the day while it was still six volts. Automotive Archeology is just as interesting as the running problem. All’s well that ends well. Glad you got it figured out. Post a photo of the car also…..fun to see people’s toys. I serviced a 42 Caddy distributor for a local friend this week……no spark condition after a intake gasket replacement. Turns out just disturbing the distributor caused the point plate to go out of position only under load over six hundred rpm’s. Crazy, but the Sun Distributor Tester found it in less than thirty seconds……in the car diagnostics would have been very difficult.

 

 

I guess I should do a post about the custom Pertronix unit I built for a special pre war customer request. It was a big boy toy……..and the customer wanted it converted to 12 Volts and electronic ignition…..but everything had to be hidden and look 100 percent stock and fit using original cap, wires, distributor, and harness. We used a simple Hall effect trigger provided by Pertronix with NO logic or timing implications. I made an eight pole billet reluctor on a dividing  head using a Bridgeport, thus the original timing advance mechanical mechanism was still in control of the timing. Made custom insulators to run the wiring through as the unit was the first thing you looked at when opening the hood. We had some issues with the magnets provided with the Hall effect sensor……but worked through them. I wouldn’t agree to do the modification today for any amount of money, but at the time I found the challenge interesting including the generator to 12v and making the 6v regulator into a 12v unit. Dash amp guage was done by someone else. The car is owned by someone who is active here and won’t admit to the “upgrade” done years ago………🤔

Edited December 15, 2023 by edinmass (see edit history)

[JimH56]

It was a combination of issues, to be sure. It was the wrong distributor for the vehicle based on Buick shop manual specifications, and the igniter experienced chafing due to the manner of its installation in the distributor. With the installation of a correct model distributor and new ignition components, the problem was solved. You might know of this 42 Sedanette, since it’s been around. When you type 42 Buick Century Sedanette into Google, this car is one often pictured. Two tone mauve and deep maroon. The old distributor was a 663E/127971. The replacement is a 1110801 and matches original spec. They are similar distributors, obviously, because the car “kinda” ran. But as time went on the damage caused to the igniter due to the configuration on the distributor plate resulted in problems.

 

The carburetor and rebuild turned out to be coincidence and not causal. In other words, fact the problem seemed to became more pronounced at that time turned out to be chance rather than cause.

[edinmass]

 

It's those crazy coincidences that make you pull your hair out. It's part of the reason why I preach to sort one system at a time. In our shop we call that situation a "since you". Since you touched it, and it broke, it's gotta be a (read as your fault) warrantee situation. 

Edited December 15, 2023 by edinmass (see edit history)

[JimH56]

A systematic and logical approach is certainly the one that will lead to the best result in my view.