1923 Buick Spark Plugs

[Guest Australian 1923]

Can anyone recommend modern spark plugs to use in my 1923/24 6 Cyl. Originals are impossible to find but modern are best for me as I use the car for touring

Thanks

David

[Fred Rawling]

Autolite #3076

[Mark Shaw]

I use Autolite 3077 in my older cars.

[Fred Rawling]

Mark,

I looked up both plugs at http://www.autolite.com. Under products, you can pull up a picture and data on the plugs.

Both plugs have the same heat range but on 3077, the porcelin and electrode extend lower than the threads.

Have you ever run the 3076 plug? I think that If I ever get my engine finished, I will try both to see how they burn.

Do you run the 0.040 gap as suggested in the David Chambers article?

Fred Rawling

[D Binger]

Fred,

I have run the 3076 in my 14 Buick B-25 for over 8 years and put maybe 3,500 miles on the car and they have done me good service. Last year I drove the Buick over 500 miles on a HCCA Tour in Oregon with out a miss. I run my gap at .025. I might try .040 and see if that might make a diffrence. I might have to get a set of 3077 plugs and see how they work. I also run the 3076 in my 22 Buick six cylinder for several years and have had no problems. The 3076 are shorter than the Champion and will not short out when I put the side cover on over the plugs.

Dan

[Brian_Heil]

3076's are the hottest I've been able to find as well after 10 years and 20,000+ miles of touring. Don't forget to put a rubber elbow boot over the tops of each to keep them from arcing to the spark plug cover since they are longer than the oringinal Titans. I take a used 90 degree spark plug boot, slit it down just the one inner side and slip/snap it over the wire and plug. The cover holds everything in place. This cured one or the 'mystery misses' my engien came with. The other was a rotated valve cage.

[Fred Rawling]

Brian,

That is a good idea about the rubber boot. What gap are you using?

Fred

[mlander]

The Champion chart @

http://www.hatraco.com/Manufact/Champion/Brochures.htm

lists W10, W14, W20 and several others with the correct 5/8? reach but one would have to study them carefully to determine the acceptable sparkplug!

One of them is a W16Y which is a standard projected core nose plug with 4 electrodes. All of these sparkplugs have 15/16? hex wrench provision the same as the Autolite.

M.L. Anderson

[Mark Shaw]

No, I have only run the 3077 plug, and yes I do gap them at .040.

[Fred Rawling]

The Champion W16Y is definately too long and will interfere with your spark plug cover. I do not know about the other numbers that you listed.

[mlander]

Re: 1923 Buick Spark Plugs [Re: Mark Shaw]

##467896 - 05/27/07 03:06 AM

The Champion W16Y is definitely too long and will interfere with your spark plug cover. I do not know about the other numbers that you listed.

I also live in Bellflower CA. Ph. 408-6737 I would like you to phone me if possible! What I would like to do is to measure a Buick cylinder head and/or an original sparkplug before they put in 18 and 14 mm sparkplugs. Usually they are ways to determine the sparkplug length without having a sparkplug in one?s hand! I will see if I can find a way.

An Autolite 3076 is 2 1/4? (2.250?) from the sparkplug washer face to the end of the terminal nut.

The ?Original Titan?? sparkplug is 1.800? from the washer face to the end of the terminal nut. This is a difference of .450? These measurements were made using a Starrett Dial Caliper. If some people claim that a Titan was the original plug then just what is the original gap at the sparkplug Boot? The Titan plug I have is completely without a number or any identification as to size etc. Only the name AC Titan is on the plug anyplace. Is it actually for a Buick I can?t say for an absolutely positive statement???!!! But the dimensions I can state are as have already stated. Of course a lot of people probably just throw away the cover.

M.L. Anderson <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />

[mlander]

Brian_Heil: rotated valve cage.

I have been studying the phrase above but my copies of the Buick Manual doesn’t seem to state just what a valve cage is and I am wondering if it has anything to do with a the valve guides?

Yours M.L. Anderson

[mlander]

The Autolite chart is at the address below and the chart for the

7/8”-18 x 5/8” reach is on page # 39. This chart comes up slowly

so one has to be patient. The 3077 is listed as being hotter than

the 3076. Both being listed as Standard Non Resistor.

35-43 lb. ft. torque.

http://wwhttp://www.noelsautoparts.com.au/Autolite%20Catalogue%20NCAP.pdfw.noelsautoparts.com.au/Autolite%20Catalogue%20NCAP.pdf

More to follow on the size and cleaning of sparkplug holes on

7/8-18 sparkplug holes only, not on millmeter types.

EDIT- JUNE-23-2007 ADDITION OF CHART 7/8"-18 SPARKPLUG HOLE VERSUS THE NEWER 7/8"-18UNS-2B THREAD.

NOTE THAT THE SPARKPLUG DIMENSIONS COME FROM AN OLD EDITION OF THE MACHINERY"S HANDBOOK 1949 AND THE NEWER 7/8"-18 UNS THREAD COMES FROM A 1996 EDITION OF MACHINERY'S HANDBOOK.

SPARKPLUG TYPE....INTERNAL......7/8”-18UNS-2B……DIFFERENCE

7/8-18 THREAD.....THREADS.......PER......................

MACHINERY’S.......SPARKPLUG………..MACHINERY’S .............

HANDBOOK 1949.....HOLE.........…HANDBOOK 1996.............

<span style="text-decoration: underline"><span style="color: #3366FF">PITCH DIA. MAX.. .8430”........ .8449”.........PLUS .0019”</span></span>

PITCH DIA. MIN.. .8389”........ .8389”............. .0000”

MINOR DIA. MAX. .8209”........ .8280”.........PLUS .0071”

MINOR DIA. MIN. .8149”........ .8150”.........PLUS .0001”

MAJOR DIA. MAX...................NONE....................

MAJOR DIA. MIN. .. .8750”........ .8750”....................

M.L. Anderson

[mlander]

After tapping out the holes we put a Champion W18 in the hole and found my little finger (About 3/8”) would go between the top of the plug and the side of the cover on the two center holes. This is not enough if no insulator Boot is used as a spark would likely jump a 5/8” gap. Someone would have to try the Rubber Boot in the top and see if that would stop any arcing. The cleaning of the sparkplug holes was very important as we wanted to check the hole with a W16Y plus a W18 fully seated to see just how much the clearance at the top of the sparkplug truly is!

Fred Rawlings and I just finished re-tapping the sparkplug holes on his two Buick 6 cylinder heads! These heads have over 50,000 miles of travel. The one head was fairly easy to retap, the reconfigured threads with the 7/8”-18 Class 3 Plug tap. Between the carbon deposits and tiny bits of cast iron and the change in threads dimension due to time and the thousands of temperature changes over a long period of time this was not as easy a task as I at first thought! Cross threading of the holes being first and foremost in our minds. After this the surface of the table showed a lot of debris of dirt and carbon flakes, more than I expected from the small “vees“ of the threads!

A careful examination of the combustion chambers revealed a “Pocket” in which the electrodes protruded and revealed the reason for the extended skirts of many old type sparkplugs before the advent of the projected corenose sparkplug. If these sparkplugs did not have a projected skirt they would have been buried about 3/8” to ½” further from the center of the combustion chamber.

Another thing that seems to be of importance is the use of the proper tap type. Taps are classified in three types, Taper, Plug and Bottoming. The one that I purchased is the Plug tap as I was very leery of the bottoming tap having no taper at the entrance end and difficulty to start into the already tapped hole. Please note the previous warning about Cross Threading the holes. In our tapping of the twelve holes it became very apparent that I should have purchased a Taper type tap for easier entrance into the already threaded hole. Another thing that seems to be of importance is the use of a wire brush of a type that will clean up the sparkplug washer face thoroughly as the one hole seemed to be “Dirty” and mismatched in this respect! Later investigation revealed it was just some more dirt!

W16Y plugs are around $6.00 which I found at NAPA and purchased one for reference. The distance from the washer face to the top end of the plug is 2.706” (2 ¾”), a very long plug!

A CHAMPION 3 Com. is about 2.312” (2-5/16“) from the washer face to the top of the plug.

The Autolite chart is at the address below and the chart for the 7/8”-18 x 5/8” reach is on page # 39. This chart comes up slowly so one has to be patient. The 3077 is listed as being hotter than the 3076. Both being listed as Standard Non Resistor. 35-43 lb. ft.

torque.

http://wwhttp://www.noelsautoparts.com.au/Autolite%20Catalogue%20NCAP.pdfw.noelsautoparts.com.au/Autolite%20Catalogue%20NCAP.pdf

The best Champion Catalog is listed below;

http://www.hatraco.com/Manufact/Champion/Brochures.htm

7/8”-18 ALL. PLUG TYPE.. REACH..... HEX........ PRICE EACH

510............... W10............. .625”............ 15/16”.......... $6.51

569............... W14............. .625”............ 15/16”............$6.51

561............... W16Y........... .625”............ 15/16”.......... $6.51

520............... W20............. .625"............ 15/16”.......... $6.51

W18 is 5/8” reach at threads but has a skirt extension making the plug from the gasket seat to the skirt ¾” long.

One thing that we must remember is that the old Cars that used these sparkplugs are not of high combustion pressures and the taps using 7/8”-18 Unified threads are likely made on the low limit of the pitch diameter tolerance. One must also remember that the Minor Diameter is not cut by the tap but by the drilling of the hole previous to tapping. The Major and Minor diameters are not a functioning portion of the tapped hole but are clearance. Only the angled faces of the thread are truly functioning parts of the threads.

This is a lot of cast iron to remove by hand on such a large thread if the hole P.D. was on the low limit of the tolerance and the cleaning tap was on the high side of the tolerance this would require a removal of some .006” off of the P.D.!

To cut these threads at the high limit of the tolerance from the low limit of the old threads would take a lot of torque.

A 7/8”-18 sparkplug hole is likely to have a lot more strength than actually needed to hold the sparkplug firmly in place. Even when NOT counting the two end threads as holding threads there is a lot of iron holding the sparkplug in place! 9¼ threads should have plenty of strength to hold the sparkplug in place. This even with the use of a high limit 7/8”-18 NS-2 tap.

Any tap ordered from the manufacturer should be very specifically one to be used for cleaning/rethreading sparkplug holes for reasons that the tap manufacturer can inform you about. The engineer at North American said that this can be very important in some cases!

There is a great deal of facts and Information on the Internet under Unified Thread and other variations of the word Unified Threads.

M.L. Anderson

[Brian_Heil]

Fred,

I too have read the Dave Chambers article about running 0.040 gap but I have run 0.025 for years. My thought being the Mallory coil I have is at least 60 years old and the smaller gap would help. (?) Next time I take them out I do plan to open them up to 0.040 and see she how she runs.

Had the pleasure to stop in and visit with Jim Milewski at his home in Rome, NY two weeks ago and help him set his timing to 14 degree more advance than stock. His '23 purred like a kitten when I left. Prior to the tune-up his spark was so far off he had a severe knock at idle.

[putize]

On 8/1/2007 at 5:48 PM, mlander said:

After tapping out the holes we put a Champion W18 in the hole and found my little finger (About 3/8”) would go between the top of the plug and the side of the cover on the two center holes. This is not enough if no insulator Boot is used as a spark would likely jump a 5/8” gap. Someone would have to try the Rubber Boot in the top and see if that would stop any arcing. The cleaning of the sparkplug holes was very important as we wanted to check the hole with a W16Y plus a W18 fully seated to see just how much the clearance at the top of the sparkplug truly is!

Fred Rawlings and I just finished re-tapping the sparkplug holes on his two Buick 6 cylinder heads! These heads have over 50,000 miles of travel. The one head was fairly easy to retap, the reconfigured threads with the 7/8”-18 Class 3 Plug tap. Between the carbon deposits and tiny bits of cast iron and the change in threads dimension due to time and the thousands of temperature changes over a long period of time this was not as easy a task as I at first thought! Cross threading of the holes being first and foremost in our minds. After this the surface of the table showed a lot of debris of dirt and carbon flakes, more than I expected from the small “vees“ of the threads!

A careful examination of the combustion chambers revealed a “Pocket” in which the electrodes protruded and revealed the reason for the extended skirts of many old type sparkplugs before the advent of the projected corenose sparkplug. If these sparkplugs did not have a projected skirt they would have been buried about 3/8” to ½” further from the center of the combustion chamber.

Another thing that seems to be of importance is the use of the proper tap type. Taps are classified in three types, Taper, Plug and Bottoming. The one that I purchased is the Plug tap as I was very leery of the bottoming tap having no taper at the entrance end and difficulty to start into the already tapped hole. Please note the previous warning about Cross Threading the holes. In our tapping of the twelve holes it became very apparent that I should have purchased a Taper type tap for easier entrance into the already threaded hole. Another thing that seems to be of importance is the use of a wire brush of a type that will clean up the sparkplug washer face thoroughly as the one hole seemed to be “Dirty” and mismatched in this respect! Later investigation revealed it was just some more dirt!

W16Y plugs are around $6.00 which I found at NAPA and purchased one for reference. The distance from the washer face to the top end of the plug is 2.706” (2 ¾”), a very long plug!

A CHAMPION 3 Com. is about 2.312” (2-5/16“) from the washer face to the top of the plug.

The Autolite chart is at the address below and the chart for the 7/8”-18 x 5/8” reach is on page # 39. This chart comes up slowly so one has to be patient. The 3077 is listed as being hotter than the 3076. Both being listed as Standard Non Resistor. 35-43 lb. ft.

torque.

http://wwhttp://www.noelsautoparts.com.au/Autolite%20Catalogue%20NCAP.pdfw.noelsautoparts.com.au/Autolite%20Catalogue%20NCAP.pdf

The best Champion Catalog is listed below;

http://www.hatraco.com/Manufact/Champion/Brochures.htm

7/8”-18 ALL. PLUG TYPE.. REACH..... HEX........ PRICE EACH

510............... W10............. .625”............ 15/16”.......... $6.51

569............... W14............. .625”............ 15/16”............$6.51

561............... W16Y........... .625”............ 15/16”.......... $6.51

520............... W20............. .625"............ 15/16”.......... $6.51

W18 is 5/8” reach at threads but has a skirt extension making the plug from the gasket seat to the skirt ¾” long.

One thing that we must remember is that the old Cars that used these sparkplugs are not of high combustion pressures and the taps using 7/8”-18 Unified threads are likely made on the low limit of the pitch diameter tolerance. One must also remember that the Minor Diameter is not cut by the tap but by the drilling of the hole previous to tapping. The Major and Minor diameters are not a functioning portion of the tapped hole but are clearance. Only the angled faces of the thread are truly functioning parts of the threads.

This is a lot of cast iron to remove by hand on such a large thread if the hole P.D. was on the low limit of the tolerance and the cleaning tap was on the high side of the tolerance this would require a removal of some .006” off of the P.D.!

To cut these threads at the high limit of the tolerance from the low limit of the old threads would take a lot of torque.

A 7/8”-18 sparkplug hole is likely to have a lot more strength than actually needed to hold the sparkplug firmly in place. Even when NOT counting the two end threads as holding threads there is a lot of iron holding the sparkplug in place! 9¼ threads should have plenty of strength to hold the sparkplug in place. This even with the use of a high limit 7/8”-18 NS-2 tap.

Any tap ordered from the manufacturer should be very specifically one to be used for cleaning/rethreading sparkplug holes for reasons that the tap manufacturer can inform you about. The engineer at North American said that this can be very important in some cases!

There is a great deal of facts and Information on the Internet under Unified Thread and other variations of the word Unified Threads.

M.L. Anderson

Hi from Athens, Hellas

Here in my country (Hellas, South Europe), I'm proud to be the sole Franklin (straight 6) 11-B (1927) owner.

It was my late father's favorite vehicle among 27 Historical Vehicles of our private Collection.

My Franklin has now W14 on it, but fellow Franklin owners from U.S suggest W18.

My technical knowledge on Franklin so far led me to fit W14 on again, as they have caused no trouble for the last 25 years.

But W18 still remain a vivid suggestion choice by American fellow Franklin owners, whom I always pay great attention to.

Can you please advise which type should I finally order? The colder W14 (now installed on my Franklin) or the hotter W18 (suggested to me by fellow owners)? I can only point out difference to reach factor (0,75" vs 0,625"), but they reassured me that I will have no problem switching W14 to W18 - they will fit like a glove on my Franklin's head.

Please, if it is convenient for you,  send me your suggestion based on your vast personal experience.

Yours

K.L.Zekakos, Dipl. Mechanical Engineer.

[Brian_Heil]

Wow, 13 years ago.
 

I think we (I) have had some learnings and some plugs have gone out of production since then. 

 

I would revise my past statement to agree that 0.035 is a better gap than 0.025. If you have a weak coil, replace it.  The coil mentioned above did finally fail. 

 

Champion W89D spark plugs are also the best for not fouling and are readily available.  I am running these in both my 1911 and 1923 Buicks.  Most importantly in the 1923 since it has original pistons with rather high oil consumption and these plugs still run clean. 

[Brian_Heil]

The same Champion plug also goes by 589 

 

I believe this is the old nomenclature since the year old plugs I have in my 1911 are W89D

 

 

[Brian_Heil]

[Brian_Heil]